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Design and analysis of an intercooled turbofan engine / Lei Xu in Transactions of the ASME . Journal of engineering for gas turbines and power, Vol. 132 N° 11 (Novembre 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 11 (Novembre 2010) . - 04 p. Titre : Design and analysis of an intercooled turbofan engine Type de document : texte imprimé Auteurs : Lei Xu, Auteur ; Tomas Grönstedt, Auteur Année de publication : 2011 Article en page(s) : 04 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Compressors  Design  engineering  Heat  transfer  Jet  engines  Optimisation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The performance of an intercooled turbofan engine is analyzed by multidisciplinary optimization. A model for making preliminary simplified analysis of the mechanical design of the engine is coupled to an aircraft model and an engine performance model. A conventional turbofan engine with technology representative for a year 2013 entry of service is compared with a corresponding intercooled engine. A mission fuel burn reduction of 3.4% is observed. The results are analyzed in terms of the relevant constraints such as compressor exit temperature, turbine entry temperature, turbine rotor blade temperature, and compressor exit blade height. It is shown that the gas path of an intercooled engine for medium range commercial transport applications, having an overall pressure ratio greater than 70 in top of climb, may still be optimized to fulfill a compressor exit blade height constraint. This indicates that a state of the art high pressure compressor efficiency can be achieved. Empirical data and a parametric computational fluid dynamics (CFD) study are used to verify the intercooler heat transfer and pressure loss characteristics. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...] [article] Design and analysis of an intercooled turbofan engine [texte imprimé] / Lei Xu, Auteur ; Tomas Grönstedt, Auteur . - 2011 . - 04 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of engineering for gas turbines and power > Vol. 132 N° 11 (Novembre 2010) . - 04 p. Mots-clés : Compressors  Design  engineering  Heat  transfer  Jet  engines  Optimisation Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The performance of an intercooled turbofan engine is analyzed by multidisciplinary optimization. A model for making preliminary simplified analysis of the mechanical design of the engine is coupled to an aircraft model and an engine performance model. A conventional turbofan engine with technology representative for a year 2013 entry of service is compared with a corresponding intercooled engine. A mission fuel burn reduction of 3.4% is observed. The results are analyzed in terms of the relevant constraints such as compressor exit temperature, turbine entry temperature, turbine rotor blade temperature, and compressor exit blade height. It is shown that the gas path of an intercooled engine for medium range commercial transport applications, having an overall pressure ratio greater than 70 in top of climb, may still be optimized to fulfill a compressor exit blade height constraint. This indicates that a state of the art high pressure compressor efficiency can be achieved. Empirical data and a parametric computational fluid dynamics (CFD) study are used to verify the intercooler heat transfer and pressure loss characteristics. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JETPEZ00013 [...]

Effect of sorbent type on the sorption enhanced water gas shift process in a fluidized bed reactor / Yang Liu in Industrial & engineering chemistry research, Vol. 51 N° 37 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 37 (Septembre 2012) . - pp. 11989–11997 Titre : Effect of sorbent type on the sorption enhanced water gas shift process in a fluidized bed reactor Type de document : texte imprimé Auteurs : Yang Liu, Auteur ; Zhenshan Li, Auteur ; Lei Xu, Auteur Année de publication : 2012 Article en page(s) : pp. 11989–11997 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Sorption  water  gas Résumé : reactions: the WGS reaction and the CaO carbonation reaction. The WGS reaction is a surface catalytic reaction, while the CaO carbonation is a bulk reaction. This study of the SEWGS reaction in a fluidized bed reactor showed that the sorbent type has an important effect on the SEWGS reaction, with both the CaO and MgO in the sorbent catalyzing the reaction. For calcined limestone, the WGS reaction occurs on the CaO surface with CO2 sorption in situ, but the reaction rate gradually decreases with the CaO conversion due to coverage by the CaCO3 product layer on the CaO surface. Thus, the shift reaction becomes the rate limiting step. For calcined dolomite, MgO in the sorbent does not react with CO2 and can then be used as a catalyst. The shift reaction is not a limiting step, with most of the CO2 for the CaO carbonation coming from the WGS reaction on the MgO surface. Even when the CaO surface is completely covered by the CaCO3 product, the MgO in the calcined dolomite is not completely covered by the CaCO3 product and can still catalyze the WGS reaction. An important phenomenon observed was that not only CaO but also MgO experienced the decay in the catalytic reactivity after multiple cycles. The decay of catalytic reactivity of MgO in dolomite is mainly the gradual covering of the MgO surface by CaO/CaCO3 grains, so most of the MgO grains will lose contact with the CO and the steam in the gas phase. The observation of encapsulation of MgO particles by CaO or CaCO3 is also important for understanding the stabilization of synthetic calcium based sorbent with support addition. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301100y [article] Effect of sorbent type on the sorption enhanced water gas shift process in a fluidized bed reactor [texte imprimé] / Yang Liu, Auteur ; Zhenshan Li, Auteur ; Lei Xu, Auteur . - 2012 . - pp. 11989–11997. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 37 (Septembre 2012) . - pp. 11989–11997 Mots-clés : Sorption  water  gas Résumé : reactions: the WGS reaction and the CaO carbonation reaction. The WGS reaction is a surface catalytic reaction, while the CaO carbonation is a bulk reaction. This study of the SEWGS reaction in a fluidized bed reactor showed that the sorbent type has an important effect on the SEWGS reaction, with both the CaO and MgO in the sorbent catalyzing the reaction. For calcined limestone, the WGS reaction occurs on the CaO surface with CO2 sorption in situ, but the reaction rate gradually decreases with the CaO conversion due to coverage by the CaCO3 product layer on the CaO surface. Thus, the shift reaction becomes the rate limiting step. For calcined dolomite, MgO in the sorbent does not react with CO2 and can then be used as a catalyst. The shift reaction is not a limiting step, with most of the CO2 for the CaO carbonation coming from the WGS reaction on the MgO surface. Even when the CaO surface is completely covered by the CaCO3 product, the MgO in the calcined dolomite is not completely covered by the CaCO3 product and can still catalyze the WGS reaction. An important phenomenon observed was that not only CaO but also MgO experienced the decay in the catalytic reactivity after multiple cycles. The decay of catalytic reactivity of MgO in dolomite is mainly the gradual covering of the MgO surface by CaO/CaCO3 grains, so most of the MgO grains will lose contact with the CO and the steam in the gas phase. The observation of encapsulation of MgO particles by CaO or CaCO3 is also important for understanding the stabilization of synthetic calcium based sorbent with support addition. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301100y