Dépouillements

Review of secondary loop refrigeration systems / Kai Wang in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 212-234 Titre : Review of secondary loop refrigeration systems Titre original : Système frigorifiques à boucle secondaire: tour d’horizon Type de document : texte imprimé Auteurs : Kai Wang, Auteur ; Magnus Eisele, Auteur ; Yunho Hwang, Auteur Année de publication : 2011 Article en page(s) : pp. 212-234 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Refrigeration  system  Review  Distribution  Hydrocarbon  Secondary  refrigerant Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Due to the environmental damage caused by HFC refrigerants, there is an increasing universal interest to research environmentally friendly fluids in refrigerants and alternative approaches to the traditional DX refrigeration system. These refrigerants include ammonia, carbon dioxide, hydrocarbon, R152a and HFO1234yf. Major drawbacks of these refrigerants are their potential flammability and safety hazards. One way to overcome this issue is to use the new refrigerants in conjunction with a secondary loop refrigeration system. Additional benefits of the secondary loop refrigeration system are refrigerant charges, leakage reduction, potential maintenance simplification, and low operating cost. This article presents a comprehensive review of the secondary loop refrigeration systems. Furthermore, this review covers the performance and risk assessment of flammable refrigerants, secondary refrigerants and components of the secondary loop refrigeration system within the following applications: commercial refrigeration, residential air conditioning/heat pumping, and mobile air conditioning. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002291 [article] Review of secondary loop refrigeration systems = Système frigorifiques à boucle secondaire: tour d’horizon [texte imprimé] / Kai Wang, Auteur ; Magnus Eisele, Auteur ; Yunho Hwang, Auteur . - 2011 . - pp. 212-234. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 212-234 Mots-clés : Refrigeration  system  Review  Distribution  Hydrocarbon  Secondary  refrigerant Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Due to the environmental damage caused by HFC refrigerants, there is an increasing universal interest to research environmentally friendly fluids in refrigerants and alternative approaches to the traditional DX refrigeration system. These refrigerants include ammonia, carbon dioxide, hydrocarbon, R152a and HFO1234yf. Major drawbacks of these refrigerants are their potential flammability and safety hazards. One way to overcome this issue is to use the new refrigerants in conjunction with a secondary loop refrigeration system. Additional benefits of the secondary loop refrigeration system are refrigerant charges, leakage reduction, potential maintenance simplification, and low operating cost. This article presents a comprehensive review of the secondary loop refrigeration systems. Furthermore, this review covers the performance and risk assessment of flammable refrigerants, secondary refrigerants and components of the secondary loop refrigeration system within the following applications: commercial refrigeration, residential air conditioning/heat pumping, and mobile air conditioning. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002291

Thermodynamic properties of eight fluorinated olefins / J. Steven Brown in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 235-241 Titre : Thermodynamic properties of eight fluorinated olefins Titre original : Propriétés thermodynamiques de huit oléfines fluorées Type de document : texte imprimé Auteurs : J. Steven Brown, Auteur ; Claudio Zilio, Auteur ; Alberto Cavallini, Auteur Année de publication : 2011 Article en page(s) : pp. 235-241 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Refrigerant  R-1225ye(E)  R1225ye(Z)  R1225zc  R1234ye(E)  R1234yf  R1234ze(E)  R1234ze(Z)  R1243zf Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Group contribution methods are used to predict the critical temperatures, critical pressures, critical densities, acentric factors, and ideal gas specific heats at constant pressure for eight fluorinated olefins, namely: R-1225ye(E), R-1225ye(Z), R-1225zc, R-1234ye(E), R-1234yf, R-1234ze(E), R-1234ze(Z), and R-1243zf. For the same eight refrigerants, the Peng–Robinson equation of state is used to predict thermodynamic properties, which are presented in pressure-enthalpy and temperature-entropy state diagrams. To provide the reader with some sense of the predictive capability of the methodology, property predictions for R-134a are compared to known data. Property predictions for R-1234yf are compared, where possible, to the open literature. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709000930 [article] Thermodynamic properties of eight fluorinated olefins = Propriétés thermodynamiques de huit oléfines fluorées [texte imprimé] / J. Steven Brown, Auteur ; Claudio Zilio, Auteur ; Alberto Cavallini, Auteur . - 2011 . - pp. 235-241. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 235-241 Mots-clés : Refrigerant  R-1225ye(E)  R1225ye(Z)  R1225zc  R1234ye(E)  R1234yf  R1234ze(E)  R1234ze(Z)  R1243zf Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Group contribution methods are used to predict the critical temperatures, critical pressures, critical densities, acentric factors, and ideal gas specific heats at constant pressure for eight fluorinated olefins, namely: R-1225ye(E), R-1225ye(Z), R-1225zc, R-1234ye(E), R-1234yf, R-1234ze(E), R-1234ze(Z), and R-1243zf. For the same eight refrigerants, the Peng–Robinson equation of state is used to predict thermodynamic properties, which are presented in pressure-enthalpy and temperature-entropy state diagrams. To provide the reader with some sense of the predictive capability of the methodology, property predictions for R-134a are compared to known data. Property predictions for R-1234yf are compared, where possible, to the open literature. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709000930

Performance of a large capacity propane heat pump with low charge heat exchangers / Alberto Cavallini in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 242-250 Titre : Performance of a large capacity propane heat pump with low charge heat exchangers Titre original : Performance d’une pompe à chaleur au propane d’une grande puissance avec des échangeurs de chaleur à faible charge Type de document : texte imprimé Auteurs : Alberto Cavallini, Auteur ; Enrico Da Riva, Auteur ; Davide Del Col, Auteur Année de publication : 2011 Article en page(s) : pp. 242-250 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  pump  Water  source  Compression  system  Propane  Experiment  Performance  Micro-channel  Reduction  Refrigerant  charge Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The experimental performance of a 100 kW heat pump using propane is presented. The charge minimization is a priority in the design of such a device and thus shell-and-tube heat exchangers using minichannels and providing low charge have been installed in the unit, along with conventional brazed plate heat exchangers, in order to compare different working configurations, both in terms of energy efficiency and refrigerant charge. The performance when using the minichannel condenser is here compared to the one obtained when using a brazed plate condenser and the influence of a minichannel internal heat exchanger on the performance of the equipment is measured and discussed. It is shown that a 100 kW heat pump without a liquid receiver could be run with around 3 kg of propane using a plate condenser and a plate evaporator. Using the minichannel condenser, around 0.8 kg reduction can be obtained with a negligible performance loss. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002448 [article] Performance of a large capacity propane heat pump with low charge heat exchangers = Performance d’une pompe à chaleur au propane d’une grande puissance avec des échangeurs de chaleur à faible charge [texte imprimé] / Alberto Cavallini, Auteur ; Enrico Da Riva, Auteur ; Davide Del Col, Auteur . - 2011 . - pp. 242-250. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 242-250 Mots-clés : Heat  pump  Water  source  Compression  system  Propane  Experiment  Performance  Micro-channel  Reduction  Refrigerant  charge Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The experimental performance of a 100 kW heat pump using propane is presented. The charge minimization is a priority in the design of such a device and thus shell-and-tube heat exchangers using minichannels and providing low charge have been installed in the unit, along with conventional brazed plate heat exchangers, in order to compare different working configurations, both in terms of energy efficiency and refrigerant charge. The performance when using the minichannel condenser is here compared to the one obtained when using a brazed plate condenser and the influence of a minichannel internal heat exchanger on the performance of the equipment is measured and discussed. It is shown that a 100 kW heat pump without a liquid receiver could be run with around 3 kg of propane using a plate condenser and a plate evaporator. Using the minichannel condenser, around 0.8 kg reduction can be obtained with a negligible performance loss. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002448

Performance enhancement of a heat pump system with ice storage subcooler / Ming-Jer Hsiao in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 251-258 Titre : Performance enhancement of a heat pump system with ice storage subcooler Titre original : Amélioration de la performance d’un système à pompe à chaleur muni d’un système de sous-refroidissement à accumulation de glace Type de document : texte imprimé Auteurs : Ming-Jer Hsiao, Auteur ; Yu-Fu Kuo, Auteur ; Chih-Chiu Shen, Auteur Année de publication : 2011 Article en page(s) : pp. 251-258 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  pump  Heating  Greenhouse  Improvement  Performance  Sub-cooling  Ice  tank Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This article experimentally investigates the thermal performance of a heat pump system with an ice storage subcooler. The system supplies heating and cooling demands to two greenhouses with temperature ranging 308∼323 K and 273∼291 K respectively and utilizes an ice storage tank to subcool the condensed refrigerant, which can enhance the system coefficient of performance (COP). The ice storage tank charges for storing ice, when the cooling load is less than the nominal cooling capacity. While the cooling load is larger than the nominal cooling capacity, the ice storage tank discharges for subcooling. The results show that in the charge mode the heat pump COP of ice storage system is 12% higher than that without ice storage tank. Under the discharge mode, the ice storage system provides the refrigerator COP 15% higher than that without ice storage tank. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002497 [article] Performance enhancement of a heat pump system with ice storage subcooler = Amélioration de la performance d’un système à pompe à chaleur muni d’un système de sous-refroidissement à accumulation de glace [texte imprimé] / Ming-Jer Hsiao, Auteur ; Yu-Fu Kuo, Auteur ; Chih-Chiu Shen, Auteur . - 2011 . - pp. 251-258. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 251-258 Mots-clés : Heat  pump  Heating  Greenhouse  Improvement  Performance  Sub-cooling  Ice  tank Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This article experimentally investigates the thermal performance of a heat pump system with an ice storage subcooler. The system supplies heating and cooling demands to two greenhouses with temperature ranging 308∼323 K and 273∼291 K respectively and utilizes an ice storage tank to subcool the condensed refrigerant, which can enhance the system coefficient of performance (COP). The ice storage tank charges for storing ice, when the cooling load is less than the nominal cooling capacity. While the cooling load is larger than the nominal cooling capacity, the ice storage tank discharges for subcooling. The results show that in the charge mode the heat pump COP of ice storage system is 12% higher than that without ice storage tank. Under the discharge mode, the ice storage system provides the refrigerator COP 15% higher than that without ice storage tank. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002497

Dynamic simulation program with object-oriented formulation for absorption chillers (modelling, verification, and application to triple-effect absorption chiller) / H. Matsushima in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 259-268 Titre : Dynamic simulation program with object-oriented formulation for absorption chillers (modelling, verification, and application to triple-effect absorption chiller) Titre original : Programme de simulation dynamique orienté objets pour les refroidisseurs à absorption (modélisation, vérification et application à un refroidisseur à absorption à triple effet) Type de document : texte imprimé Auteurs : H. Matsushima, Auteur ; T. Fujii, Auteur ; T. Komatsu, Auteur Année de publication : 2011 Article en page(s) : pp. 259-268 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Air  conditioning  Chiller  Absorption  system  Water/lithium  bromide  Modelling  Simulation  Transient  state Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A new dynamic simulation program for predicting the transient behavior of absorption chillers with arbitrary cycle configurations has been developed. This program combines an object-oriented formulation and a parallel processing program architecture. A new algorithm for calculating the flow rate in a solution circulation line has been also developed. The simulated results of transient behavior of a double-effect absorption chiller cycle agree with the measured behavior of a machine from startup to shutdown. For example, predicted values of the cooling capacity of the chiller, the pressure and temperature of the high temperature generator agree with experimental values almost within 10%. This program has been applied in the development stage of a new machine: a high-performance triple-effect absorption chiller. As a result, this machine operates smoothly without any significant problems, and achieves COP of over 1.6 on the basis of high heat value. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709001650 [article] Dynamic simulation program with object-oriented formulation for absorption chillers (modelling, verification, and application to triple-effect absorption chiller) = Programme de simulation dynamique orienté objets pour les refroidisseurs à absorption (modélisation, vérification et application à un refroidisseur à absorption à triple effet) [texte imprimé] / H. Matsushima, Auteur ; T. Fujii, Auteur ; T. Komatsu, Auteur . - 2011 . - pp. 259-268. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 259-268 Mots-clés : Air  conditioning  Chiller  Absorption  system  Water/lithium  bromide  Modelling  Simulation  Transient  state Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A new dynamic simulation program for predicting the transient behavior of absorption chillers with arbitrary cycle configurations has been developed. This program combines an object-oriented formulation and a parallel processing program architecture. A new algorithm for calculating the flow rate in a solution circulation line has been also developed. The simulated results of transient behavior of a double-effect absorption chiller cycle agree with the measured behavior of a machine from startup to shutdown. For example, predicted values of the cooling capacity of the chiller, the pressure and temperature of the high temperature generator agree with experimental values almost within 10%. This program has been applied in the development stage of a new machine: a high-performance triple-effect absorption chiller. As a result, this machine operates smoothly without any significant problems, and achieves COP of over 1.6 on the basis of high heat value. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709001650

The effects of nanoparticles on absorption heat and mass transfer performance in NH3/H2O binary nanofluids / Jin Ki Lee in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 269-275 Titre : The effects of nanoparticles on absorption heat and mass transfer performance in NH3/H2O binary nanofluids Titre original : Titre Les effets des nanoparticules sur le transfert de chaleur et de masse lors de l’absorption des nanofluides binaires au NH3/H2O Type de document : texte imprimé Auteurs : Jin Ki Lee, Auteur ; Junemo Koo, Auteur ; Hiki Hong, Auteur Année de publication : 2011 Article en page(s) : pp. 269-275 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Absorption  system  Ammonia-water  Experiment  Additive  Aqueous  solution  Particle  Oxide  Aluminium  Nanotube  Mass  transfer  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The objectives of this paper are to examine the effect of nanoparticles on the pool type absorption heat transfer enhancement and to find the optimal conditions to design a highly effective compact absorber for NH3/H2O absorption system. The binary nanofluids which mean binary mixture with nano-sized particles are tested to apply nanofluids to the absorption system. Al2O3 and carbon nanotube (CNT) particles are added to make the binary nanofluids in the binary mixture of NH3/H2O. The effect of Al2O3 nanoparticles and CNT on the absorption performance is studied experimentally. The experimental ranges of the key parameters are 20% of NH3 concentration, 0–0.08 vol% (volume fraction) of CNT particles, and 0–0.06 vol% of Al2O3 nanoparticles. For the NH3/H2O nanofluids, the heat transfer rate and absorption rate with 0.02 vol% Al2O3 nanoparticles were found to be 29% and 18% higher than those without nanoparticles, respectively. It is recommended that the concentration of 0.02 vol% of Al2O3 nanoparticles be the best candidate for NH3/H2O absorption performance enhancement in the present conditions. It is expected that this study will give some basic idea to understand the heat and mass transfer enhancement mechanism in multi-components nanofluids. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002382 [article] The effects of nanoparticles on absorption heat and mass transfer performance in NH3/H2O binary nanofluids = Titre Les effets des nanoparticules sur le transfert de chaleur et de masse lors de l’absorption des nanofluides binaires au NH3/H2O [texte imprimé] / Jin Ki Lee, Auteur ; Junemo Koo, Auteur ; Hiki Hong, Auteur . - 2011 . - pp. 269-275. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 269-275 Mots-clés : Absorption  system  Ammonia-water  Experiment  Additive  Aqueous  solution  Particle  Oxide  Aluminium  Nanotube  Mass  transfer  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The objectives of this paper are to examine the effect of nanoparticles on the pool type absorption heat transfer enhancement and to find the optimal conditions to design a highly effective compact absorber for NH3/H2O absorption system. The binary nanofluids which mean binary mixture with nano-sized particles are tested to apply nanofluids to the absorption system. Al2O3 and carbon nanotube (CNT) particles are added to make the binary nanofluids in the binary mixture of NH3/H2O. The effect of Al2O3 nanoparticles and CNT on the absorption performance is studied experimentally. The experimental ranges of the key parameters are 20% of NH3 concentration, 0–0.08 vol% (volume fraction) of CNT particles, and 0–0.06 vol% of Al2O3 nanoparticles. For the NH3/H2O nanofluids, the heat transfer rate and absorption rate with 0.02 vol% Al2O3 nanoparticles were found to be 29% and 18% higher than those without nanoparticles, respectively. It is recommended that the concentration of 0.02 vol% of Al2O3 nanoparticles be the best candidate for NH3/H2O absorption performance enhancement in the present conditions. It is expected that this study will give some basic idea to understand the heat and mass transfer enhancement mechanism in multi-components nanofluids. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002382

The performance analysis of a novel dual evaporator type three-bed adsorption chiller / Miyazaki, Toshimasa in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 276-285 Titre : The performance analysis of a novel dual evaporator type three-bed adsorption chiller Titre original : Analyse de la performance de deux nouveaux évaporateurs pour un refroidisseur à adsorption à trois adsorbeurs Type de document : texte imprimé Auteurs : Miyazaki, Toshimasa, Auteur ; Atsushi Akisawa, Auteur ; Bidyut Baran Saha, Auteur Année de publication : 2011 Article en page(s) : pp. 276-285 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Air  conditioning  Adsorption  system  Calculation  Performance  Modelling  Simulation  Parameter  Geometry Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper deals with the performance evaluation of an innovative, waste heat driven dual evaporator type three-bed adsorption cycle for cooling application. The innovative adsorption chiller has two evaporators, three adsorbent beds, and a condenser, and the evaporators work at different pressure levels. The effects of hot water inlet temperature, chilled water inlet and outlet temperatures, and cycle time on the specific cooling capacity (SCC) and coefficient of performance (COP) were predicted by simulation. For the same operating condition, the SCC and COP of the dual evaporator type three-bed adsorption chiller were found to be 1.5 and 1.7 times higher than those of the two-bed single-stage adsorption chiller, respectively. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002394 [article] The performance analysis of a novel dual evaporator type three-bed adsorption chiller = Analyse de la performance de deux nouveaux évaporateurs pour un refroidisseur à adsorption à trois adsorbeurs [texte imprimé] / Miyazaki, Toshimasa, Auteur ; Atsushi Akisawa, Auteur ; Bidyut Baran Saha, Auteur . - 2011 . - pp. 276-285. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 276-285 Mots-clés : Air  conditioning  Adsorption  system  Calculation  Performance  Modelling  Simulation  Parameter  Geometry Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : This paper deals with the performance evaluation of an innovative, waste heat driven dual evaporator type three-bed adsorption cycle for cooling application. The innovative adsorption chiller has two evaporators, three adsorbent beds, and a condenser, and the evaporators work at different pressure levels. The effects of hot water inlet temperature, chilled water inlet and outlet temperatures, and cycle time on the specific cooling capacity (SCC) and coefficient of performance (COP) were predicted by simulation. For the same operating condition, the SCC and COP of the dual evaporator type three-bed adsorption chiller were found to be 1.5 and 1.7 times higher than those of the two-bed single-stage adsorption chiller, respectively. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002394

A dynamic 1-D model for a reciprocating active magnetic regenerator; influence of the main working parameters / G. Tagliafico in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 286-293 Titre : A dynamic 1-D model for a reciprocating active magnetic regenerator; influence of the main working parameters Titre original : Modèle dynamique unidimensionnel pour un régénérateur actif magnétique; influence des paramètres de fonctionnement principaux Type de document : texte imprimé Auteurs : G. Tagliafico, Auteur ; F. Scarpa, Auteur ; F. Canepa, Auteur Année de publication : 2011 Article en page(s) : pp. 286-293 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Magnetic  refrigerator  Modelling  Simulation  Performance  Parameter  Regenerator Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Active Magnetic Regeneration (AMR) is a configuration that allows magnetic refrigeration to be suitable also for room temperature applications. This work is intended to detect, by means of a 1-D numerical model, the influence on the regenerator performances of the working condition ambient temperature (TCURIE ± 20 K) and of the operating parameters fluid mass flow rate (utilization factor 0.5÷3.5) and cycle frequency (0.1÷0.6 Hz). Simulations show that, tuning the fluid mass flow rate, a gadolinium AMR (395 g, f = 0.25 Hz, ΔB = 1.7 T) can reach a maximum cooling capacity of 130 W and a 40 W cooling power over a temperature span of 30 K. A COP of 5 can also be achieved with a temperature span of 30 K and a cooling power of 35 W. Frequency has a weak influence on the AMR's COP, while the ambient temperature is crucial. The system loses the 60% of cooling capacity if the ambient temperature is 20 K away from the material Curie temperature. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002321 [article] A dynamic 1-D model for a reciprocating active magnetic regenerator; influence of the main working parameters = Modèle dynamique unidimensionnel pour un régénérateur actif magnétique; influence des paramètres de fonctionnement principaux [texte imprimé] / G. Tagliafico, Auteur ; F. Scarpa, Auteur ; F. Canepa, Auteur . - 2011 . - pp. 286-293. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 286-293 Mots-clés : Magnetic  refrigerator  Modelling  Simulation  Performance  Parameter  Regenerator Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Active Magnetic Regeneration (AMR) is a configuration that allows magnetic refrigeration to be suitable also for room temperature applications. This work is intended to detect, by means of a 1-D numerical model, the influence on the regenerator performances of the working condition ambient temperature (TCURIE ± 20 K) and of the operating parameters fluid mass flow rate (utilization factor 0.5÷3.5) and cycle frequency (0.1÷0.6 Hz). Simulations show that, tuning the fluid mass flow rate, a gadolinium AMR (395 g, f = 0.25 Hz, ΔB = 1.7 T) can reach a maximum cooling capacity of 130 W and a 40 W cooling power over a temperature span of 30 K. A COP of 5 can also be achieved with a temperature span of 30 K and a cooling power of 35 W. Frequency has a weak influence on the AMR's COP, while the ambient temperature is crucial. The system loses the 60% of cooling capacity if the ambient temperature is 20 K away from the material Curie temperature. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002321

Development of a rotary magnetic refrigerator / Jaka Tušek in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 294-300 Titre : Development of a rotary magnetic refrigerator Titre original : Développement d’un réfrigérateur magnétique rotati Type de document : texte imprimé Auteurs : Jaka Tušek, Auteur ; Samo Zupan, Auteur ; Alen Šarlah, Auteur Année de publication : 2011 Article en page(s) : pp. 294-300 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Magnetic  refrigerator  Design  Construction  Magnet  Gadolinium Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A team of researchers have developed and built a prototype of a rotary magnetic refrigerator (MR). The principle of the operation of the presented magnetic refrigerator is based on the rotary movement of active magnetic regenerators (AMRs) with a magnetocaloric material and on the magnetic field generated by permanent magnets Nd–Fe–B. The first part of the paper presents the development and analysis of the structure for generating the magnetic field and the basic operational principle of the magnetic refrigerator concerned, and the second part gives a description of the development process for certain key elements of the complete magnetic refrigeration system. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002503 [article] Development of a rotary magnetic refrigerator = Développement d’un réfrigérateur magnétique rotati [texte imprimé] / Jaka Tušek, Auteur ; Samo Zupan, Auteur ; Alen Šarlah, Auteur . - 2011 . - pp. 294-300. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 294-300 Mots-clés : Magnetic  refrigerator  Design  Construction  Magnet  Gadolinium Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A team of researchers have developed and built a prototype of a rotary magnetic refrigerator (MR). The principle of the operation of the presented magnetic refrigerator is based on the rotary movement of active magnetic regenerators (AMRs) with a magnetocaloric material and on the magnetic field generated by permanent magnets Nd–Fe–B. The first part of the paper presents the development and analysis of the structure for generating the magnetic field and the basic operational principle of the magnetic refrigerator concerned, and the second part gives a description of the development process for certain key elements of the complete magnetic refrigeration system. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002503

Performance enhancement study of mobile air conditioning system using microchannel heat exchangers / Zhaogang Qi in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 301-312 Titre : Performance enhancement study of mobile air conditioning system using microchannel heat exchangers Titre original : Amélioration de la performance d'un système de conditionnement d'air automobile à l'aide d'échangeurs de chaleur à microcanaux Type de document : texte imprimé Auteurs : Zhaogang Qi, Auteur ; Yu Zhao, Auteur ; Jiangping Chen, Auteur Année de publication : 2011 Article en page(s) : pp. 301-312 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Air  conditioning  Automobile  Heat  exchanger  Microchannel  R134a  Improvement  Performance Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In the present paper, two retrofitted compact and high efficient microchannel heat exchangers were proposed. The new microchannel heat exchangers have advantages in compactness (17.2% and 15.1% volume reduction for evaporator and condenser, respectively), weight (2.8% and 14.9% lighter for evaporator and condenser, respectively), heat transfer characteristics compared with the currently used heat exchangers in mobile air conditioning (MAC) industry. One enhanced and one baseline R134a MAC systems were established including the new microchannel heat exchangers and the traditional MAC heat exchangers, respectively. The system performances have been experimentally carried out under variable ambient conditions in psychrometric calorimeter test bench. The optimal system refrigerant charge amounts for both systems were tested and the results showed that the enhanced system with more compact heat exchangers could reduce system charge amount and the minimum effective charge amount was less than that of the baseline system. The enhanced system could supply more cooling capacity to car compartment under all test conditions because of higher performance heat exchangers. The coefficient of performance (COP) of the enhanced system was slightly lower than that of the baseline system under idle conditions but higher under all the other test conditions. Cooling capacity and COP of the enhanced system was increased by about 5% and 8% under high vehicle speed condition. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900200X [article] Performance enhancement study of mobile air conditioning system using microchannel heat exchangers = Amélioration de la performance d'un système de conditionnement d'air automobile à l'aide d'échangeurs de chaleur à microcanaux [texte imprimé] / Zhaogang Qi, Auteur ; Yu Zhao, Auteur ; Jiangping Chen, Auteur . - 2011 . - pp. 301-312. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 301-312 Mots-clés : Air  conditioning  Automobile  Heat  exchanger  Microchannel  R134a  Improvement  Performance Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In the present paper, two retrofitted compact and high efficient microchannel heat exchangers were proposed. The new microchannel heat exchangers have advantages in compactness (17.2% and 15.1% volume reduction for evaporator and condenser, respectively), weight (2.8% and 14.9% lighter for evaporator and condenser, respectively), heat transfer characteristics compared with the currently used heat exchangers in mobile air conditioning (MAC) industry. One enhanced and one baseline R134a MAC systems were established including the new microchannel heat exchangers and the traditional MAC heat exchangers, respectively. The system performances have been experimentally carried out under variable ambient conditions in psychrometric calorimeter test bench. The optimal system refrigerant charge amounts for both systems were tested and the results showed that the enhanced system with more compact heat exchangers could reduce system charge amount and the minimum effective charge amount was less than that of the baseline system. The enhanced system could supply more cooling capacity to car compartment under all test conditions because of higher performance heat exchangers. The coefficient of performance (COP) of the enhanced system was slightly lower than that of the baseline system under idle conditions but higher under all the other test conditions. Cooling capacity and COP of the enhanced system was increased by about 5% and 8% under high vehicle speed condition. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900200X

Air-side heat transfer characteristics of spiral-type circular fin-tube heat exchangers / Mooyeon Lee in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 313-320 Titre : Air-side heat transfer characteristics of spiral-type circular fin-tube heat exchangers Titre original : Caractéristiques de transfert de chaleur côté air des échangeurs de chaleur circulaires hélicoïdaux à tubes ailetés Type de document : texte imprimé Auteurs : Mooyeon Lee, Auteur ; Taehyung Kang, Auteur ; Yongchan Kim, Auteur Année de publication : 2011 Article en page(s) : pp. 313-320 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Chiller  Heat  exchanger  Finned  tube  Spiral  Geometry  Experiment  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The objective of this study is to investigate the air-side heat transfer characteristics of spiral-type circular fin-tube heat exchangers used as evaporators in household refrigerators. The j-factors of the tested heat exchangers under non-frosting conditions were measured by varying the fin pitch, number of tube rows, and fin alignment. The j-factors of the spiral-type circular fin-tube heat exchangers were analyzed as a function of heat exchanger geometries and then compared with those of the flat plate fin-tube heat exchangers with discrete fins. Two empirical correlations of the j-factors were developed separately for the inline and the staggered fin alignment as a function of the Reynolds number, number of tube rows, and dimensionless fin pitch normalized by the hydraulic diameter. The mean deviation of the predictions using the present correlations from the measured data was 4.78% for the inline fin alignment and 6.02% for the staggered fin alignment. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002308 [article] Air-side heat transfer characteristics of spiral-type circular fin-tube heat exchangers = Caractéristiques de transfert de chaleur côté air des échangeurs de chaleur circulaires hélicoïdaux à tubes ailetés [texte imprimé] / Mooyeon Lee, Auteur ; Taehyung Kang, Auteur ; Yongchan Kim, Auteur . - 2011 . - pp. 313-320. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 313-320 Mots-clés : Chiller  Heat  exchanger  Finned  tube  Spiral  Geometry  Experiment  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The objective of this study is to investigate the air-side heat transfer characteristics of spiral-type circular fin-tube heat exchangers used as evaporators in household refrigerators. The j-factors of the tested heat exchangers under non-frosting conditions were measured by varying the fin pitch, number of tube rows, and fin alignment. The j-factors of the spiral-type circular fin-tube heat exchangers were analyzed as a function of heat exchanger geometries and then compared with those of the flat plate fin-tube heat exchangers with discrete fins. Two empirical correlations of the j-factors were developed separately for the inline and the staggered fin alignment as a function of the Reynolds number, number of tube rows, and dimensionless fin pitch normalized by the hydraulic diameter. The mean deviation of the predictions using the present correlations from the measured data was 4.78% for the inline fin alignment and 6.02% for the staggered fin alignment. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002308

A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions / Y. Xia in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 321-333 Titre : A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions Titre original : Un modèle pour la prévision de la performance thermohydraulique d'échangeurs de chaleur à ailettes à persienne à tubes plats sous des conditions de givrage Type de document : texte imprimé Auteurs : Y. Xia, Auteur ; A. M. Jacobi, Auteur Année de publication : 2011 Article en page(s) : pp. 321-333 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Finned  tube  Louvered  fin  Geometry  Modeling  Performance  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Correlations and a model are developed to predict the time-varying performance of folded-louvered-fin, microchannel heat exchangers. The model utilizes the correlations developed from the experimental data and incorporates a sub-model for frost properties. The model successfully predicts the heat transfer performance of the heat exchangers studied, but its ability to predict the pressure-drop behavior needs further improvement. The model can be used to evaluate geometry effects on the frosting behavior of the louvered-fin, microchannel heat exchangers, and can be easily generalized to other applications with simultaneous heat and mass transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002357 [article] A model for predicting the thermal-hydraulic performance of louvered-fin, flat-tube heat exchangers under frosting conditions = Un modèle pour la prévision de la performance thermohydraulique d'échangeurs de chaleur à ailettes à persienne à tubes plats sous des conditions de givrage [texte imprimé] / Y. Xia, Auteur ; A. M. Jacobi, Auteur . - 2011 . - pp. 321-333. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 321-333 Mots-clés : Heat  exchanger  Finned  tube  Louvered  fin  Geometry  Modeling  Performance  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Correlations and a model are developed to predict the time-varying performance of folded-louvered-fin, microchannel heat exchangers. The model utilizes the correlations developed from the experimental data and incorporates a sub-model for frost properties. The model successfully predicts the heat transfer performance of the heat exchangers studied, but its ability to predict the pressure-drop behavior needs further improvement. The model can be used to evaluate geometry effects on the frosting behavior of the louvered-fin, microchannel heat exchangers, and can be easily generalized to other applications with simultaneous heat and mass transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002357

Effect of some geometric parameters on performance of PF2 heat exchangers in periodic frosting / Ping Zhang in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 334-346 Titre : Effect of some geometric parameters on performance of PF2 heat exchangers in periodic frosting Titre original : Impact de certains paramètres sur la performance d'échangeurs à écoulements et aux ailettes parallèles lors d'épisodes périodiques de givrage Type de document : texte imprimé Auteurs : Ping Zhang, Auteur ; P. S. Hrnjak, Auteur Année de publication : 2011 Article en page(s) : pp. 334-346 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Finned  tube  Experiment  Performance  Parameter  Geometry  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The thermal performance under conditions of initial frost growth and subsequent refrosting after a defrost is experimentally studied for the parallel flow parallel fin (PF2) heat exchanger, a new style of heat exchanger that uses louvered bent fins on flat tubes to enhance water drainage when the flat tubes are horizontal (typically outdoor heat exchanger in heat pump operation). This paper focuses on quantification of the effects of geometry (i.e. fin pitch 12–22 fpi and louver pitch 1.4–2.8 mm) on defrost and refrost times. Eight heat exchangers differing in louver pitch and fin spacing are studied. A series of tests are conducted in search for the best geometry. The effects of geometry on heat transfer (thermal performance) and pressure drop for air face velocities of 0.9, 2, and 3 m/s are determined and used for comparison. Characteristics of initial heat transfer coefficient and pressure drop during the first frosting cycle are reported in terms of Colburn j0 factor and Fanning friction f0 factor, as a function of ReLp and geometry. The newly developed air-side correlations for PF2 heat exchangers (Colburn j0 factor and Fanning friction f0 factor) predict the test data within rms error of ±10%, and with mean deviation of 2.95% and 4.98%, respectively. The correlations are base on a very low Reynolds numbers in the range of 100–620, and 8 PF2 heat exchangers using 48 experimental data. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002515 [article] Effect of some geometric parameters on performance of PF2 heat exchangers in periodic frosting = Impact de certains paramètres sur la performance d'échangeurs à écoulements et aux ailettes parallèles lors d'épisodes périodiques de givrage [texte imprimé] / Ping Zhang, Auteur ; P. S. Hrnjak, Auteur . - 2011 . - pp. 334-346. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 334-346 Mots-clés : Heat  exchanger  Finned  tube  Experiment  Performance  Parameter  Geometry  Frosting Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The thermal performance under conditions of initial frost growth and subsequent refrosting after a defrost is experimentally studied for the parallel flow parallel fin (PF2) heat exchanger, a new style of heat exchanger that uses louvered bent fins on flat tubes to enhance water drainage when the flat tubes are horizontal (typically outdoor heat exchanger in heat pump operation). This paper focuses on quantification of the effects of geometry (i.e. fin pitch 12–22 fpi and louver pitch 1.4–2.8 mm) on defrost and refrost times. Eight heat exchangers differing in louver pitch and fin spacing are studied. A series of tests are conducted in search for the best geometry. The effects of geometry on heat transfer (thermal performance) and pressure drop for air face velocities of 0.9, 2, and 3 m/s are determined and used for comparison. Characteristics of initial heat transfer coefficient and pressure drop during the first frosting cycle are reported in terms of Colburn j0 factor and Fanning friction f0 factor, as a function of ReLp and geometry. The newly developed air-side correlations for PF2 heat exchangers (Colburn j0 factor and Fanning friction f0 factor) predict the test data within rms error of ±10%, and with mean deviation of 2.95% and 4.98%, respectively. The correlations are base on a very low Reynolds numbers in the range of 100–620, and 8 PF2 heat exchangers using 48 experimental data. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002515

Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles / Peng, Hao in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 347-358 Titre : Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles Titre original : Caractéristiques du transfert de chaleur lors de l'ébullition libre nucléée d'un mélange frigorigène/huile aux nanoparticules de diamant Type de document : texte imprimé Auteurs : Peng, Hao, Auteur ; Guoliang Ding, Auteur ; Haitao Hu, Auteur Année de publication : 2011 Article en page(s) : pp. 347-358 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Refrigerant  Mixture  Oil  Additive  Particle  Experiment  Heat  transfer  Pool  boiling Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles were investigated experimentally. The refrigerant is R113 and the oil is VG68. Experimental conditions include a saturation pressure of 101.3 kPa, heat fluxes from 10 to 80 kW m−2, nanoparticles concentrations in the nanoparticles/oil suspension from 0 to 15 wt%, and nanoparticles/oil suspension concentrations from 0 to 5 wt%. The experimental results indicate that the nucleate pool boiling heat transfer coefficient of R113/oil mixture with diamond nanoparticles is larger than that of R113/oil mixture by maximum of 63.4% under the present experimental conditions, and the enhancement increases with the increase of nanoparticles concentration in the nanoparticles/oil suspension and decreases with the increase of nanoparticles/oil suspension concentration. A correlation for predicting the nucleate pool boiling heat transfer coefficient of refrigerant/oil mixture with nanoparticles is proposed, and it agrees well with the experimental data of refrigerant/oil mixture with nanoparticles. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002679 [article] Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles = Caractéristiques du transfert de chaleur lors de l'ébullition libre nucléée d'un mélange frigorigène/huile aux nanoparticules de diamant [texte imprimé] / Peng, Hao, Auteur ; Guoliang Ding, Auteur ; Haitao Hu, Auteur . - 2011 . - pp. 347-358. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 347-358 Mots-clés : Refrigerant  Mixture  Oil  Additive  Particle  Experiment  Heat  transfer  Pool  boiling Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles were investigated experimentally. The refrigerant is R113 and the oil is VG68. Experimental conditions include a saturation pressure of 101.3 kPa, heat fluxes from 10 to 80 kW m−2, nanoparticles concentrations in the nanoparticles/oil suspension from 0 to 15 wt%, and nanoparticles/oil suspension concentrations from 0 to 5 wt%. The experimental results indicate that the nucleate pool boiling heat transfer coefficient of R113/oil mixture with diamond nanoparticles is larger than that of R113/oil mixture by maximum of 63.4% under the present experimental conditions, and the enhancement increases with the increase of nanoparticles concentration in the nanoparticles/oil suspension and decreases with the increase of nanoparticles/oil suspension concentration. A correlation for predicting the nucleate pool boiling heat transfer coefficient of refrigerant/oil mixture with nanoparticles is proposed, and it agrees well with the experimental data of refrigerant/oil mixture with nanoparticles. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002679

Local boiling heat transfer characteristics of ammonia in a vertical plate evaporator / H. Arima in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 359-370 Titre : Local boiling heat transfer characteristics of ammonia in a vertical plate evaporator Titre original : Caractéristiques de transfert de chaleur lors de l’ébullition locale d’ammoniac dans un évaporateur à plaque verticale Type de document : texte imprimé Auteurs : H. Arima, Auteur ; J.H. Kim, Auteur ; A. Okamoto, Auteur Année de publication : 2011 Article en page(s) : pp. 359-370 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Plate  exchanger  Heat  transfer  Boiling  Ammonia  Measurement  Heat  transfer  coefficient  Visualization Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Ocean thermal energy conversion systems are expected to be the next-generation energy production systems. In these systems, a plate heat exchanger is used for improving the power generation efficiency, and ammonia or an ammonia/water mixture is used as a working fluid. In this study, boiling heat transfer coefficients of pure ammonia are measured on a vertical flat PHE (a plate heat exchanger), for elucidating and characterizing the behavior of ammonia on a compact plate evaporator, a type of PHE The measurement results show that local boiling heat transfer coefficients increase with increasing vapor quality. Further, the effects of saturation pressure, mass flow rate, and average heat flux on the boiling heat transfer coefficient are elucidated. An empirical correlation for the local boiling heat transfer coefficient is derived using the Lockhart-Martinelli parameter. Further, a visualization experiment of boiling phenomena of ammonia is performed to elucidate the relation between boiling behavior and heat transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900228X [article] Local boiling heat transfer characteristics of ammonia in a vertical plate evaporator = Caractéristiques de transfert de chaleur lors de l’ébullition locale d’ammoniac dans un évaporateur à plaque verticale [texte imprimé] / H. Arima, Auteur ; J.H. Kim, Auteur ; A. Okamoto, Auteur . - 2011 . - pp. 359-370. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 359-370 Mots-clés : Heat  exchanger  Plate  exchanger  Heat  transfer  Boiling  Ammonia  Measurement  Heat  transfer  coefficient  Visualization Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Ocean thermal energy conversion systems are expected to be the next-generation energy production systems. In these systems, a plate heat exchanger is used for improving the power generation efficiency, and ammonia or an ammonia/water mixture is used as a working fluid. In this study, boiling heat transfer coefficients of pure ammonia are measured on a vertical flat PHE (a plate heat exchanger), for elucidating and characterizing the behavior of ammonia on a compact plate evaporator, a type of PHE The measurement results show that local boiling heat transfer coefficients increase with increasing vapor quality. Further, the effects of saturation pressure, mass flow rate, and average heat flux on the boiling heat transfer coefficient are elucidated. An empirical correlation for the local boiling heat transfer coefficient is derived using the Lockhart-Martinelli parameter. Further, a visualization experiment of boiling phenomena of ammonia is performed to elucidate the relation between boiling behavior and heat transfer. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900228X

Experimental study on saturated flow boiling heat transfer of R170/R290 mixtures in a horizontal tube / X. Zou in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 371-380 Titre : Experimental study on saturated flow boiling heat transfer of R170/R290 mixtures in a horizontal tube Titre original : Etude expérimentale sur le transfert de chaleur lors de l’ébullition en écoulement saturé des mélanges de R170 et de R290 à l’intérieur d’un tube horizontal Type de document : texte imprimé Auteurs : X. Zou, Auteur ; M.Q. Gong, Auteur ; G. F. Chen, Auteur Année de publication : 2011 Article en page(s) : pp. 371-380 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Evaporator  Horizontal  tube  Experiment  Heat  transfer  Mixture  Ethane  Propane Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Saturated flow boiling heat transfer coefficients in a horizontal tube of the binary mixtures of R170/R290 were measured. The experiments were performed at three different mixture compositions and various saturation pressures from 0.35 to 0.57 MPa. The results were obtained over the mass fluxes ranging from 63.6 to 102.5 kg m−2 s−1 and heat fluxes ranging from 13.1 to 65.5 kW m−2. The influences of quality, saturation pressure, heat flux and mass flux on the heat transfer characteristic were examined and discussed. The flow pattern of mixture was shown and the transitions of flow pattern occur at higher mass flux and quality for mixtures than for pure substance. A modified correlation was developed based on the previous research of our group on the pool boiling heat transfer and the database obtained from this study. The comparison of the experimental heat transfer coefficient with the predicted value using the present correlation shows that the total mean deviation is 15.97% for R170/R290 mixtures. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002473 [article] Experimental study on saturated flow boiling heat transfer of R170/R290 mixtures in a horizontal tube = Etude expérimentale sur le transfert de chaleur lors de l’ébullition en écoulement saturé des mélanges de R170 et de R290 à l’intérieur d’un tube horizontal [texte imprimé] / X. Zou, Auteur ; M.Q. Gong, Auteur ; G. F. Chen, Auteur . - 2011 . - pp. 371-380. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 371-380 Mots-clés : Heat  exchanger  Evaporator  Horizontal  tube  Experiment  Heat  transfer  Mixture  Ethane  Propane Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Saturated flow boiling heat transfer coefficients in a horizontal tube of the binary mixtures of R170/R290 were measured. The experiments were performed at three different mixture compositions and various saturation pressures from 0.35 to 0.57 MPa. The results were obtained over the mass fluxes ranging from 63.6 to 102.5 kg m−2 s−1 and heat fluxes ranging from 13.1 to 65.5 kW m−2. The influences of quality, saturation pressure, heat flux and mass flux on the heat transfer characteristic were examined and discussed. The flow pattern of mixture was shown and the transitions of flow pattern occur at higher mass flux and quality for mixtures than for pure substance. A modified correlation was developed based on the previous research of our group on the pool boiling heat transfer and the database obtained from this study. The comparison of the experimental heat transfer coefficient with the predicted value using the present correlation shows that the total mean deviation is 15.97% for R170/R290 mixtures. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002473

Dynamic simulation of reciprocating refrigeration compressors and experimental validation / Jean Castaing-Lasvignottes in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 381-389 Titre : Dynamic simulation of reciprocating refrigeration compressors and experimental validation Titre original : Simulation dynamique des compresseurs frigorifiques à piston et validation expérimentale Type de document : texte imprimé Auteurs : Jean Castaing-Lasvignottes, Auteur ; Stéphane Gibout, Auteur Année de publication : 2011 Article en page(s) : pp. 381-389 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Sorption  Compression  system  Modelling  Simulation  Volumetric  efficiency  Efficiency Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Among the various ways to simulate compressor behaviour, using efficiency definitions such as volumetric, isentropic or effective is relatively easy to perform and rapid when dynamic simulation is required. Calculating these efficiencies and their dependence on operating pressure, refrigerant type, and temperature is on the contrary relatively difficult to estimate. The approach presented here supposes that they depend essentially on two parameters, the dead volume ratio, having a particular influence on volumetric efficiency, and a friction factor mainly influencing both isentropic and effective efficiencies. The bases of the model are tested for a reversible and for a non-reversible reciprocating compressor when simulated over a compression cycle and dead volume ratio and friction factor influence is studied and discussed. Finally, the model is compared to experiments and allows validating the method, giving quite accurate results. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002412 [article] Dynamic simulation of reciprocating refrigeration compressors and experimental validation = Simulation dynamique des compresseurs frigorifiques à piston et validation expérimentale [texte imprimé] / Jean Castaing-Lasvignottes, Auteur ; Stéphane Gibout, Auteur . - 2011 . - pp. 381-389. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 381-389 Mots-clés : Sorption  Compression  system  Modelling  Simulation  Volumetric  efficiency  Efficiency Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Among the various ways to simulate compressor behaviour, using efficiency definitions such as volumetric, isentropic or effective is relatively easy to perform and rapid when dynamic simulation is required. Calculating these efficiencies and their dependence on operating pressure, refrigerant type, and temperature is on the contrary relatively difficult to estimate. The approach presented here supposes that they depend essentially on two parameters, the dead volume ratio, having a particular influence on volumetric efficiency, and a friction factor mainly influencing both isentropic and effective efficiencies. The bases of the model are tested for a reversible and for a non-reversible reciprocating compressor when simulated over a compression cycle and dead volume ratio and friction factor influence is studied and discussed. Finally, the model is compared to experiments and allows validating the method, giving quite accurate results. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002412

Refrigerant concentration measurement at compressor oil sump by refractive index (concentration of R410A in PVE oil) / Mitsuhiro Fukuta in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 390-397 Titre : Refrigerant concentration measurement at compressor oil sump by refractive index (concentration of R410A in PVE oil) Titre original : Mesures de la concentration du frigorigène dans le carter du compresseur à l'aide de l'indice de réfraction (concentration de R410A dans l'huile polyvinyléther - PVE) Type de document : texte imprimé Auteurs : Mitsuhiro Fukuta, Auteur ; Masahiro Ito, Auteur ; Tadashi Yanagisawa, Auteur Année de publication : 2011 Article en page(s) : pp. 390-397 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Compressor  Concentration  Measurement  Oil  R410A  Refrigerant Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The dissolution of refrigerant into refrigeration oil has great influence on oil viscosity. In this study, a refractive index measurement is applied to measure the refrigerant concentration in the oil at a compressor oil sump. Although the refractive index of the oil/refrigerant mixture is correlated with the refrigerant concentration using the refractive indices of the oil and the refrigerant, the temperature of the oil in the compressor is so high that the refractive index of the refrigerant cannot be defined because the temperature surpasses the critical temperature of the refrigerant. Therefore the correlation under such high temperature conditions is examined. It is found to be reasonable to use the refractive index of the refrigerant derived by an extrapolation of the refractive indices of the saturated liquid refrigerant under a sub-critical condition. In addition, a transient measurement of the refrigerant concentration in the oil was carried out in a practically operated compressor. Although the output signal of the sensor is disturbed by bubbles generated during the separation of the refrigerant from the oil, a data processing procedure which eliminates the over-ranged signal and averages the output within a certain time period is proposed for eliminating the influence of the bubbles. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002163 [article] Refrigerant concentration measurement at compressor oil sump by refractive index (concentration of R410A in PVE oil) = Mesures de la concentration du frigorigène dans le carter du compresseur à l'aide de l'indice de réfraction (concentration de R410A dans l'huile polyvinyléther - PVE) [texte imprimé] / Mitsuhiro Fukuta, Auteur ; Masahiro Ito, Auteur ; Tadashi Yanagisawa, Auteur . - 2011 . - pp. 390-397. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 390-397 Mots-clés : Compressor  Concentration  Measurement  Oil  R410A  Refrigerant Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : The dissolution of refrigerant into refrigeration oil has great influence on oil viscosity. In this study, a refractive index measurement is applied to measure the refrigerant concentration in the oil at a compressor oil sump. Although the refractive index of the oil/refrigerant mixture is correlated with the refrigerant concentration using the refractive indices of the oil and the refrigerant, the temperature of the oil in the compressor is so high that the refractive index of the refrigerant cannot be defined because the temperature surpasses the critical temperature of the refrigerant. Therefore the correlation under such high temperature conditions is examined. It is found to be reasonable to use the refractive index of the refrigerant derived by an extrapolation of the refractive indices of the saturated liquid refrigerant under a sub-critical condition. In addition, a transient measurement of the refrigerant concentration in the oil was carried out in a practically operated compressor. Although the output signal of the sensor is disturbed by bubbles generated during the separation of the refrigerant from the oil, a data processing procedure which eliminates the over-ranged signal and averages the output within a certain time period is proposed for eliminating the influence of the bubbles. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002163

Independent air dehumidification with membrane-based total heat recovery / C. H. Liang in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 398-408 Titre : Independent air dehumidification with membrane-based total heat recovery : Modeling and experimental validation Titre original : Déshumidification de l'air indépendante à l'aide de récupération de chaleur complète grâce à une membrane: modélisation et validation expérimentale Type de document : texte imprimé Auteurs : C. H. Liang, Auteur ; L.Z. Zhang, Auteur ; L.X. Pei, Auteur Année de publication : 2011 Article en page(s) : pp. 398-408 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Air  conditioning  Dehumidification  Membrane  Heat  recovery  Modelling  Experiment Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Fresh air ventilation is helpful for the control of epidemic respiratory disease like Swine flu (H1N1). Fresh air dehumidification systems with energy recovery measures are the key equipments to realize this goal. As a solution, an independent air dehumidification system with membrane-based total heat recovery is proposed. A prototype is built in laboratory. A detailed model is proposed and a cell-by-cell simulation technique is used in simulation to evaluate performances. The results indicate that the model can predict the system accurately. The effects of varying operating conditions like air-flow rates, temperature, and air relative humidity on the air dehumidification rates, cooling powers, electric power consumption, and thermal coefficient of performance are evaluated. The prototype has a COP of 6.8 under nominal operating conditions with total heat recovery. The performance is rather robust to outside weather conditions with a membrane-based total heat exchanger. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002175 [article] Independent air dehumidification with membrane-based total heat recovery = Déshumidification de l'air indépendante à l'aide de récupération de chaleur complète grâce à une membrane: modélisation et validation expérimentale : Modeling and experimental validation [texte imprimé] / C. H. Liang, Auteur ; L.Z. Zhang, Auteur ; L.X. Pei, Auteur . - 2011 . - pp. 398-408. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 398-408 Mots-clés : Air  conditioning  Dehumidification  Membrane  Heat  recovery  Modelling  Experiment Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Fresh air ventilation is helpful for the control of epidemic respiratory disease like Swine flu (H1N1). Fresh air dehumidification systems with energy recovery measures are the key equipments to realize this goal. As a solution, an independent air dehumidification system with membrane-based total heat recovery is proposed. A prototype is built in laboratory. A detailed model is proposed and a cell-by-cell simulation technique is used in simulation to evaluate performances. The results indicate that the model can predict the system accurately. The effects of varying operating conditions like air-flow rates, temperature, and air relative humidity on the air dehumidification rates, cooling powers, electric power consumption, and thermal coefficient of performance are evaluated. The prototype has a COP of 6.8 under nominal operating conditions with total heat recovery. The performance is rather robust to outside weather conditions with a membrane-based total heat exchanger. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002175

Predictive functional control of an expansion valve for minimizing the superheat of an evaporator / H. Fallahsohi in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 409-418 Titre : Predictive functional control of an expansion valve for minimizing the superheat of an evaporator Titre original : Régulation prévisionnelle d'un détendeur utilisé pour réduire la surchauffe d'un évaporateur Type de document : texte imprimé Auteurs : H. Fallahsohi, Auteur ; C. Changenet, Auteur ; S. Placé, Auteur Année de publication : 2011 Article en page(s) : pp. 409-418 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Refrigeration  system  Direct  expansion  Control  Superheat  Evaporator  Energy  saving Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In a previous paper, a Predictive Functional Control (PFC) method was proposed to control the evaporator superheat with an electronic expansion valve. It has been shown that superheat may be more accurately controlled by PFC than the conventional Proportional-Integral-Derivative (PID) control. In this paper, the proposed methodology is extended to regulate the condensing pressure. In order to study the influence of this control method on the Coefficient of Performance (COP), experiments are conducted on a refrigerating machine by changing the cooling capacity from 120 to 30 kW. As PFC improves disturbance rejection compared to a PID control, it is possible to reduce the superheat setting value and to prevent any unevaporated refrigerant liquid from reaching the compressor. As a consequence the use of PFC leads to an increase of COP which depends on operating conditions. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002424 [article] Predictive functional control of an expansion valve for minimizing the superheat of an evaporator = Régulation prévisionnelle d'un détendeur utilisé pour réduire la surchauffe d'un évaporateur [texte imprimé] / H. Fallahsohi, Auteur ; C. Changenet, Auteur ; S. Placé, Auteur . - 2011 . - pp. 409-418. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 409-418 Mots-clés : Refrigeration  system  Direct  expansion  Control  Superheat  Evaporator  Energy  saving Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In a previous paper, a Predictive Functional Control (PFC) method was proposed to control the evaporator superheat with an electronic expansion valve. It has been shown that superheat may be more accurately controlled by PFC than the conventional Proportional-Integral-Derivative (PID) control. In this paper, the proposed methodology is extended to regulate the condensing pressure. In order to study the influence of this control method on the Coefficient of Performance (COP), experiments are conducted on a refrigerating machine by changing the cooling capacity from 120 to 30 kW. As PFC improves disturbance rejection compared to a PID control, it is possible to reduce the superheat setting value and to prevent any unevaporated refrigerant liquid from reaching the compressor. As a consequence the use of PFC leads to an increase of COP which depends on operating conditions. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002424

Study of scraping force of ice growing on cooling solid surface / Koji Matsumoto in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 419-427 Titre : Study of scraping force of ice growing on cooling solid surface Titre original : Etude sur la force de raclage de la glace formée sur une surface solide refroidie Type de document : texte imprimé Auteurs : Koji Matsumoto, Auteur ; Takahiro Akimoto, Auteur ; Yoshikazu Teraoka, Auteur Année de publication : 2011 Article en page(s) : pp. 419-427 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Thermal  storage  Ice  tank  Measurement  Mechanical  property  Adhesion  Ice  Scraped  surface  Ice  slurry Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In a dynamic ice storage system, one of typical methods to form ice slurry is a “Harvest method” where ice growing on the cooling surface is scraped by a rotary knife. This method has an advantage that ice adhesion to a cooling wall, which is a serious problem in a conventional method, is not necessary to be considered. In this study, ice was formed on a carbon steel surface by cooling an ethylene-glycol solution with stirring, and ice growing on the cooling surface was scraped. At that time, scraping force was measured, varying supercooling degrees of the solution, ice formation times, concentrations of the solution and surface temperatures and surface roughness of the carbon steel. And, influences of the above parameters on scraping force were clarified, and behaviors of ice scraped from the carbon steel surface were classified. Moreover, ice growing on the surface was continuously scraped repeatedly. At that time, influence of the number of scrapings on scraping force was clarified. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900245X [article] Study of scraping force of ice growing on cooling solid surface = Etude sur la force de raclage de la glace formée sur une surface solide refroidie [texte imprimé] / Koji Matsumoto, Auteur ; Takahiro Akimoto, Auteur ; Yoshikazu Teraoka, Auteur . - 2011 . - pp. 419-427. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 419-427 Mots-clés : Thermal  storage  Ice  tank  Measurement  Mechanical  property  Adhesion  Ice  Scraped  surface  Ice  slurry Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : In a dynamic ice storage system, one of typical methods to form ice slurry is a “Harvest method” where ice growing on the cooling surface is scraped by a rotary knife. This method has an advantage that ice adhesion to a cooling wall, which is a serious problem in a conventional method, is not necessary to be considered. In this study, ice was formed on a carbon steel surface by cooling an ethylene-glycol solution with stirring, and ice growing on the cooling surface was scraped. At that time, scraping force was measured, varying supercooling degrees of the solution, ice formation times, concentrations of the solution and surface temperatures and surface roughness of the carbon steel. And, influences of the above parameters on scraping force were clarified, and behaviors of ice scraped from the carbon steel surface were classified. Moreover, ice growing on the surface was continuously scraped repeatedly. At that time, influence of the number of scrapings on scraping force was clarified. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S014070070900245X

Dynamic surface tension of heat transfer additives suitable for use in steam condensers and absorbers / Yong-Du Jun in International journal of refrigeration, Vol. 33 N° 2 (Mars 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 428-434 Titre : Dynamic surface tension of heat transfer additives suitable for use in steam condensers and absorbers Titre original : Tension superficielle dynamique des additifs favorisant le transfert de chaleur adaptés à l’utilisation dans les condenseurs de vapeur et les absorbeurs Type de document : texte imprimé Auteurs : Yong-Du Jun, Auteur ; Kwang J. Kim, Auteur ; John M. Kennedy, Auteur Année de publication : 2011 Article en page(s) : pp. 428-434 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Heat  exchanger  Absorber  Condenser  Measurement  Surface  tension  Additive  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Additives are often effectively used in enhancing heat transfer by creating a surface tension gradient on the surface of a condensate film to induce Marangoni driven “dropwise-like” condensation. The objective of the current study is to use the Maximum Bubble Pressure Method (MBPM) to evaluate dynamic behavior of the surface tension of solutions of three different additives (2-ethoxy ethanol, isobutylamine, and 2-ethyl-1-hexanol) of varying concentrations with water. It was shown that the effects of 2-ethoxy ethanol on surface tension was primarily dependent on solute concentration and showed little dependence on time (i.e. surface age of bubble). While both isobutylamine and 2-ethyl-1-hexanol showed strong dependence on both concentration and time, the effects of the later were far more dramatic. The results for all solutions are presented as functions of concentration and time (i.e. surface age of bubble). DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002667 [article] Dynamic surface tension of heat transfer additives suitable for use in steam condensers and absorbers = Tension superficielle dynamique des additifs favorisant le transfert de chaleur adaptés à l’utilisation dans les condenseurs de vapeur et les absorbeurs [texte imprimé] / Yong-Du Jun, Auteur ; Kwang J. Kim, Auteur ; John M. Kennedy, Auteur . - 2011 . - pp. 428-434. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 2 (Mars 2010) . - pp. 428-434 Mots-clés : Heat  exchanger  Absorber  Condenser  Measurement  Surface  tension  Additive  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Additives are often effectively used in enhancing heat transfer by creating a surface tension gradient on the surface of a condensate film to induce Marangoni driven “dropwise-like” condensation. The objective of the current study is to use the Maximum Bubble Pressure Method (MBPM) to evaluate dynamic behavior of the surface tension of solutions of three different additives (2-ethoxy ethanol, isobutylamine, and 2-ethyl-1-hexanol) of varying concentrations with water. It was shown that the effects of 2-ethoxy ethanol on surface tension was primarily dependent on solute concentration and showed little dependence on time (i.e. surface age of bubble). While both isobutylamine and 2-ethyl-1-hexanol showed strong dependence on both concentration and time, the effects of the later were far more dramatic. The results for all solutions are presented as functions of concentration and time (i.e. surface age of bubble). DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700709002667

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