Documents disponibles écrits par cet auteur

A computationally efficient hybrid leakage model for positive displacement compressors and expanders / Ian H. Bell in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1965–1973 Titre : A computationally efficient hybrid leakage model for positive displacement compressors and expanders Titre original : Modèle hybride des fuites fiable sur le plan des calculs, pour les compresseurs volumétriques et les détendeurs Type de document : texte imprimé Auteurs : Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur Année de publication : 2014 Article en page(s) : pp. 1965–1973 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Compressor;  Expanders;  Simulation;  Leakage Résumé : An empirical frictional correction factor to the isentropic nozzle model has been developed for application to refrigerant leakage modeling in scroll, rotary and other similar compressors and expanders. This correction factor is derived by calculating the leakage mass flow rate with a compressible, variable area, real gas properties model and referencing the results to an isentropic nozzle model. The ratio of flows is correlated to the Reynolds number, a characteristic length and the leakage gap width. A representative selection of fluids and geometries are employed. For all the correlations, at least 93% of the points are predicted within an absolute error band of 20%. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713000200 [article] A computationally efficient hybrid leakage model for positive displacement compressors and expanders = Modèle hybride des fuites fiable sur le plan des calculs, pour les compresseurs volumétriques et les détendeurs [texte imprimé] / Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur . - 2014 . - pp. 1965–1973. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1965–1973 Mots-clés : Compressor;  Expanders;  Simulation;  Leakage Résumé : An empirical frictional correction factor to the isentropic nozzle model has been developed for application to refrigerant leakage modeling in scroll, rotary and other similar compressors and expanders. This correction factor is derived by calculating the leakage mass flow rate with a compressible, variable area, real gas properties model and referencing the results to an isentropic nozzle model. The ratio of flows is correlated to the Reynolds number, a characteristic length and the leakage gap width. A representative selection of fluids and geometries are employed. For all the correlations, at least 93% of the points are predicted within an absolute error band of 20%. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713000200

Experimental testing of an oil-flooded hermetic scroll compressor / Ian H. Bell in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1866–1873 Titre : Experimental testing of an oil-flooded hermetic scroll compressor Titre original : Essais expérimentaux effectués sur un compresseur à spirale hermétique noyé par l'huile Type de document : texte imprimé Auteurs : Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur Année de publication : 2014 Article en page(s) : pp. 1866–1873 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Air  conditioning;  Refrigeration;  Flooded  compression Résumé : In this work, a residential air conditioning compressor designed for vapor injection has been modified in order to inject large quantities of oil into the working chamber in order to approach an isothermal compression process. The compressor was tested with oil injection mass flow fractions of up to 45%. At an evaporating temperature of −10 °C and condensing temperature of 30 °C, the overall isentropic efficiency was up to 70% at the highest oil injection rate. Overall, over the testing envelope investigated, there are no significantly negative effects experienced for the compressor and the compressor isentropic efficiency and refrigerant mass flow rate improve monotonically as the oil injection rate is increased. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713000212 [article] Experimental testing of an oil-flooded hermetic scroll compressor = Essais expérimentaux effectués sur un compresseur à spirale hermétique noyé par l'huile [texte imprimé] / Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur . - 2014 . - pp. 1866–1873. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1866–1873 Mots-clés : Air  conditioning;  Refrigeration;  Flooded  compression Résumé : In this work, a residential air conditioning compressor designed for vapor injection has been modified in order to inject large quantities of oil into the working chamber in order to approach an isothermal compression process. The compressor was tested with oil injection mass flow fractions of up to 45%. At an evaporating temperature of −10 °C and condensing temperature of 30 °C, the overall isentropic efficiency was up to 70% at the highest oil injection rate. Overall, over the testing envelope investigated, there are no significantly negative effects experienced for the compressor and the compressor isentropic efficiency and refrigerant mass flow rate improve monotonically as the oil injection rate is increased. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713000212

Performance of vapor compression systems with compressor oil flooding and regeneration / Ian H. Bell in International journal of refrigeration, Vol. 34 N° 1 (Janvier 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 1 (Janvier 2011) . - pp. 225-233 Titre : Performance of vapor compression systems with compressor oil flooding and regeneration Titre original : Performance des systèmes à compression de vapeur munis de compresseurs avec suralimentation en huile et régénération Type de document : texte imprimé Auteurs : Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur Année de publication : 2011 Article en page(s) : pp. 225-233 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Air-conditioning  Refrigeration  Regeneration  Flooding  Efficiency-compression Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Vapor compression refrigeration technology has seen great improvement over the last several decades in terms of cycle efficiency through a concerted effort of manufacturers, regulators, and research engineers. As the standard vapor compression systems approach practical limits, cycle modifications should be investigated to increase system efficiency and capacity. One possible means of increasing cycle efficiency is to flood the compressor with a large quantity of oil to achieve a quasi-isothermal compression process, in addition to using a regenerator to increase refrigerant subcooling. In theory, compressor flooding and regeneration can provide a significant increase in system efficiency over the standard vapor compression system. The effectiveness of compressor flooding and regeneration increases as the temperature lift of the system increases. Therefore, this technology is particularly well suited towards lower evaporating temperatures and high ambient temperatures as seen in supermarket refrigeration applications. While predicted increases in cycle efficiency are over 40% for supermarket refrigeration applications, this technology is still very beneficial for typical air-conditioning applications, for which improvements in cycle efficiency greater than 5% are predicted. It has to be noted though that the beneficial effects of compressor flooding can only be realized if a regenerator is used to exchange heat between the refrigerant vapor exiting the evaporator and the liquid exiting the condenser. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002094 [article] Performance of vapor compression systems with compressor oil flooding and regeneration = Performance des systèmes à compression de vapeur munis de compresseurs avec suralimentation en huile et régénération [texte imprimé] / Ian H. Bell, Auteur ; Eckhard A. Groll, Auteur ; James E. Braun, Auteur . - 2011 . - pp. 225-233. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 1 (Janvier 2011) . - pp. 225-233 Mots-clés : Air-conditioning  Refrigeration  Regeneration  Flooding  Efficiency-compression Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Vapor compression refrigeration technology has seen great improvement over the last several decades in terms of cycle efficiency through a concerted effort of manufacturers, regulators, and research engineers. As the standard vapor compression systems approach practical limits, cycle modifications should be investigated to increase system efficiency and capacity. One possible means of increasing cycle efficiency is to flood the compressor with a large quantity of oil to achieve a quasi-isothermal compression process, in addition to using a regenerator to increase refrigerant subcooling. In theory, compressor flooding and regeneration can provide a significant increase in system efficiency over the standard vapor compression system. The effectiveness of compressor flooding and regeneration increases as the temperature lift of the system increases. Therefore, this technology is particularly well suited towards lower evaporating temperatures and high ambient temperatures as seen in supermarket refrigeration applications. While predicted increases in cycle efficiency are over 40% for supermarket refrigeration applications, this technology is still very beneficial for typical air-conditioning applications, for which improvements in cycle efficiency greater than 5% are predicted. It has to be noted though that the beneficial effects of compressor flooding can only be realized if a regenerator is used to exchange heat between the refrigerant vapor exiting the evaporator and the liquid exiting the condenser. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002094