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Experimental study on ammonia-water falling film absorption in external magnetic fields / Xiao Feng Niu in International journal of refrigeration, Vol. 33 N° 4 (Juin 2010) 

Public ISBD [article]  in International journal of refrigeration > Vol. 33 N° 4 (Juin 2010) . - pp. 686-694 Titre : Experimental study on ammonia-water falling film absorption in external magnetic fields Titre original : Etude éxperimentale sur l’absorption d’un film tombant à ammoniac/eau dans les champs magnétiques externes Type de document : texte imprimé Auteurs : Xiao Feng Niu, Auteur ; Kai Du, Auteur ; Fu Xiao, Auteur Année de publication : 2010 Article en page(s) : pp. 686-694 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Absorption  system  Ammonia-water  Experiment  Falling  film  Absorber  Magnetic  field Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Experiments of ammonia–water falling film absorption were performed in magnetic fields of different intensities and different directions as well as under varied operating conditions. Experimental results showed that the outlet concentration of ammonia–water, the outlet temperature of cooling water and the amount of absorption heat and mass in downward magnetic field are higher than those in non-magnetic field. However, all of them decreased in the upward magnetic field. Therefore, it can be concluded that the magnetic field with the same direction as falling film enhances the absorption, and the magnetic field with the direction against falling film weakens the absorption of ammonia–water. The results also showed the effect of magnetic field on absorption was more obvious in solutions with low inlet concentration. The influences of the cooling water flow rate, the cooling water inlet temperature and the solution flow rate on absorption in magnetic field were similar to those without magnetic field. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710000204 [article] Experimental study on ammonia-water falling film absorption in external magnetic fields = Etude éxperimentale sur l’absorption d’un film tombant à ammoniac/eau dans les champs magnétiques externes [texte imprimé] / Xiao Feng Niu, Auteur ; Kai Du, Auteur ; Fu Xiao, Auteur . - 2010 . - pp. 686-694. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 33 N° 4 (Juin 2010) . - pp. 686-694 Mots-clés : Absorption  system  Ammonia-water  Experiment  Falling  film  Absorber  Magnetic  field Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Experiments of ammonia–water falling film absorption were performed in magnetic fields of different intensities and different directions as well as under varied operating conditions. Experimental results showed that the outlet concentration of ammonia–water, the outlet temperature of cooling water and the amount of absorption heat and mass in downward magnetic field are higher than those in non-magnetic field. However, all of them decreased in the upward magnetic field. Therefore, it can be concluded that the magnetic field with the same direction as falling film enhances the absorption, and the magnetic field with the direction against falling film weakens the absorption of ammonia–water. The results also showed the effect of magnetic field on absorption was more obvious in solutions with low inlet concentration. The influences of the cooling water flow rate, the cooling water inlet temperature and the solution flow rate on absorption in magnetic field were similar to those without magnetic field. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710000204

Experimental study on enhancement of ammonia–water falling film absorption by adding nano-particles / Liu Yang in International journal of refrigeration, Vol. 34 N° 3 (Mai 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 3 (Mai 2011) . - pp. 640-647 Titre : Experimental study on enhancement of ammonia–water falling film absorption by adding nano-particles Titre original : Etude expérimentale sur l'amélioration de l'absorption d'un film tombant utilisant une solution d'ammoniac/eau à l'aide de l'ajout de nanoparticules Type de document : texte imprimé Auteurs : Liu Yang, Auteur ; Kai Du, Auteur ; Xiao Feng Niu, Auteur Année de publication : 2011 Article en page(s) : pp. 640-647 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Ammonia–water  Falling  film  Absorption  Mass  transfer  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Based on the preparation of Al2O3, Fe2O3 and ZnFe2O4 nanofluid, the comparative experiments on the falling film absorption between ammonia–water and ammonia–water with various kinds of nano-particles are carried out. Experimental results show that the sorts and mass fraction of nano-particles, the viscosity and stability of nanofluid, as well as the mass fraction of ammonia in the basefluid are considered as the key parameters. The absorption of ammonia is weakened by only adding surfactants or adding poorly dispersed nano-particles. The increase of mass fraction of nano-particles with matched surfactants can improve the absorption rate of ammonia under the condition that the viscosity of nanofluid does not increase remarkably, and there is an optimal mass fraction for each kind of nano-particles and surfactant. With the increase in ammonia mass fraction of initial nanofluid, the absorption potential capacity decline, but the enhancing effect induced by the nanofluid is more obvious compared to that without nano-particles. The effective absorption ratio can be increased by 70% and 50% with Fe2O3 and ZnFe2O4 nanofluid respectively when the initial ammonia mass fraction is 15%. The absorption enhancement by the nanofluid is attributable to the heat transfer enhancement and the decrease in viscosity of nanofluid, which are strongly proved by the temperature differences in cooling water and nanofluids as well as the falling film flowing time. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002926 [article] Experimental study on enhancement of ammonia–water falling film absorption by adding nano-particles = Etude expérimentale sur l'amélioration de l'absorption d'un film tombant utilisant une solution d'ammoniac/eau à l'aide de l'ajout de nanoparticules [texte imprimé] / Liu Yang, Auteur ; Kai Du, Auteur ; Xiao Feng Niu, Auteur . - 2011 . - pp. 640-647. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 3 (Mai 2011) . - pp. 640-647 Mots-clés : Ammonia–water  Falling  film  Absorption  Mass  transfer  Heat  transfer Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : Based on the preparation of Al2O3, Fe2O3 and ZnFe2O4 nanofluid, the comparative experiments on the falling film absorption between ammonia–water and ammonia–water with various kinds of nano-particles are carried out. Experimental results show that the sorts and mass fraction of nano-particles, the viscosity and stability of nanofluid, as well as the mass fraction of ammonia in the basefluid are considered as the key parameters. The absorption of ammonia is weakened by only adding surfactants or adding poorly dispersed nano-particles. The increase of mass fraction of nano-particles with matched surfactants can improve the absorption rate of ammonia under the condition that the viscosity of nanofluid does not increase remarkably, and there is an optimal mass fraction for each kind of nano-particles and surfactant. With the increase in ammonia mass fraction of initial nanofluid, the absorption potential capacity decline, but the enhancing effect induced by the nanofluid is more obvious compared to that without nano-particles. The effective absorption ratio can be increased by 70% and 50% with Fe2O3 and ZnFe2O4 nanofluid respectively when the initial ammonia mass fraction is 15%. The absorption enhancement by the nanofluid is attributable to the heat transfer enhancement and the decrease in viscosity of nanofluid, which are strongly proved by the temperature differences in cooling water and nanofluids as well as the falling film flowing time. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002926