Axisymmetric coupled thermoelasticity is investigated by finite element method,and the inertia effect is also considered.A quasi-thermal conduction equation is obtained through transformation.A numerical algorithm is ...Axisymmetric coupled thermoelasticity is investigated by finite element method,and the inertia effect is also considered.A quasi-thermal conduction equation is obtained through transformation.A numerical algorithm is proposed based on the Newmark technology.The effect of inertia and coupling is investigated.展开更多
In order to identify the locations of irreversible loss within the transcritical carbon dioxide refrigeration cycle with an expansion turbine, a method with respect to the second law of thermodynamics based on exergy ...In order to identify the locations of irreversible loss within the transcritical carbon dioxide refrigeration cycle with an expansion turbine, a method with respect to the second law of thermodynamics based on exergy analysis model is applied. The effects of heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures on the exergy loss, exergy efficiency and the coefficient of performance (COP) of the expansion turbine cycle are analyzed. It is found that the great percentages of exergy losses take place in the gas cooler and compressor. Moreover, heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures have strong influence on the exergy efficiency, COP and the exergy loss of each component. The analysis shows that there exists an optimal heat rejection pressure corresponding to the maximum exergy efficiency and COP, respectively. The results are of significance in providing theoretical basis for optimal design and the control of the transcritical carbon dioxide system with an expansion turbine.展开更多
This report reviews the development of the theoretical framework for exergoeconomics, and proposes a time and space-dependent exergy cost transfer equation. The exergy cost transfer equation, together with the exergy ...This report reviews the development of the theoretical framework for exergoeconomics, and proposes a time and space-dependent exergy cost transfer equation. The exergy cost transfer equation, together with the exergy transfer equation, constitutes the theoretical fundament for exergy analysis, exergoeconomic analysis and optimization. With these transfer equations, three theorems regarding to exergoeconomics are therefore derived, expounded and proved, which could be utilized to solve problems in esti- mating exergy, exergy fluxes and exergy destruction costing.展开更多
文摘Axisymmetric coupled thermoelasticity is investigated by finite element method,and the inertia effect is also considered.A quasi-thermal conduction equation is obtained through transformation.A numerical algorithm is proposed based on the Newmark technology.The effect of inertia and coupling is investigated.
基金SupportedbytheSpecializedResearchFundfortheDoctoralProgramofHigherEducation (No .D0 2 0 0 10 5)
文摘In order to identify the locations of irreversible loss within the transcritical carbon dioxide refrigeration cycle with an expansion turbine, a method with respect to the second law of thermodynamics based on exergy analysis model is applied. The effects of heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures on the exergy loss, exergy efficiency and the coefficient of performance (COP) of the expansion turbine cycle are analyzed. It is found that the great percentages of exergy losses take place in the gas cooler and compressor. Moreover, heat rejection pressures, outlet temperatures of gas cooler and evaporating temperatures have strong influence on the exergy efficiency, COP and the exergy loss of each component. The analysis shows that there exists an optimal heat rejection pressure corresponding to the maximum exergy efficiency and COP, respectively. The results are of significance in providing theoretical basis for optimal design and the control of the transcritical carbon dioxide system with an expansion turbine.
基金supported by the Major State Basic Research Development Program(Grant No.G2000026307)the National Natural Science Foundation of China(Grant No.20076018).
文摘This report reviews the development of the theoretical framework for exergoeconomics, and proposes a time and space-dependent exergy cost transfer equation. The exergy cost transfer equation, together with the exergy transfer equation, constitutes the theoretical fundament for exergy analysis, exergoeconomic analysis and optimization. With these transfer equations, three theorems regarding to exergoeconomics are therefore derived, expounded and proved, which could be utilized to solve problems in esti- mating exergy, exergy fluxes and exergy destruction costing.
