The high aerodynamic noise induced by automotive air conditioning systems has important effects on the ride comfort, and the centrifugal fan is the largest noise source in these systems. It is very important to reduce...The high aerodynamic noise induced by automotive air conditioning systems has important effects on the ride comfort, and the centrifugal fan is the largest noise source in these systems. It is very important to reduce the aerodynamic noise generated by the centrifugal fan. The flow field and the sound field on the whole centrifugal fan configuration have been carried out using the computational fluid dynamics. Simulation results show that the sound pressure level near the outlet of the centrifugal fan is too high. Based on the relationship between flow characteristics and the aerodynamic noise, four parameters of the centrifugal fan, i.e., impeller blade's outlet angle 0, volute tongue's gap t, collector inclination angle fl, and rotating speed n, were selected as design variables and optimized using response surface methodology. While keeping the function of flow rate unchanged, the peak noise level is reduced by 8 dB or 10.8%. The noise level is satisfactorily reduced.展开更多
In this paper, the feasibility of application of a solid-absorption system using ammonia and chlorides as working pair to automobile air-conditioning system is investigated. This system has the advantages of minimum e...In this paper, the feasibility of application of a solid-absorption system using ammonia and chlorides as working pair to automobile air-conditioning system is investigated. This system has the advantages of minimum environmental problem and utilizing waste heat from the automobile engine as thermal energy input. Analyses show that the main problem associated with the application of solid-absorption system is the size of the reactors. Techniques to solve this problem are discussed.展开更多
基金Project(50975083) supported by the National Natural Science Foundation of ChinaProject(61075001) supported by China State Key Laboratory of Advanced Design and Manufacturing for Vehicle BodyProject(201-IV-068) supported by the Fundamental Research Funds for the Central Universities,China
文摘The high aerodynamic noise induced by automotive air conditioning systems has important effects on the ride comfort, and the centrifugal fan is the largest noise source in these systems. It is very important to reduce the aerodynamic noise generated by the centrifugal fan. The flow field and the sound field on the whole centrifugal fan configuration have been carried out using the computational fluid dynamics. Simulation results show that the sound pressure level near the outlet of the centrifugal fan is too high. Based on the relationship between flow characteristics and the aerodynamic noise, four parameters of the centrifugal fan, i.e., impeller blade's outlet angle 0, volute tongue's gap t, collector inclination angle fl, and rotating speed n, were selected as design variables and optimized using response surface methodology. While keeping the function of flow rate unchanged, the peak noise level is reduced by 8 dB or 10.8%. The noise level is satisfactorily reduced.
文摘In this paper, the feasibility of application of a solid-absorption system using ammonia and chlorides as working pair to automobile air-conditioning system is investigated. This system has the advantages of minimum environmental problem and utilizing waste heat from the automobile engine as thermal energy input. Analyses show that the main problem associated with the application of solid-absorption system is the size of the reactors. Techniques to solve this problem are discussed.