Bao Tao1,Sun Zongxin1,Yuan Xiuling1,Chen Yunguang1,Wang Kaijun2£¬Dong Xiaojun2
£¨1£®School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an ¡¡710049,China;2.Technique Center of Thermo King Transport Refrigeration Co.Ltd.in Asia£¬ Shenzhen 518040,China)
Abstract£ºTwo return air openings instead of one were adopted to improve the air distribution circulating system in the bus air conditioning device.The standard k-¦Å turbulence model and wall function were used in the investigation. Numerical simulations were performed comparatively for the situations with and without the improvement.The results demonstrate that the inside air temperatures tend to be more uniform after improvement of return air openings£® The temperature in the front and rear of the bus drops obviously and that in the middle part rises slightly.The inside average temperature is more uniform and is 0.5 K lower at the same supply air temperature of 289.15 K£® So the supply air temperature can be raised and the energy efficiency can be higher at the same inside temperature.Also,the temperature difference between the head and foot regions decreases,with 2 K drop at both ends,and a slight rise at mid part,which can offer better thermal comfort in much wider area£®
Keywords£ºbus air conditioning£» airflow distribution£» numerical simulation