基于分析的单螺杆压缩机轴功利用效率研究

Study on Usage Efficiency of Single Screw Compressor's Shaft Power Based on Exergy Analysis Method

运用火用方法对车载燃料电池系统单螺杆压缩机压缩过程中的轴功利用效率以及耗散方式进行研究。分析了由气体泄漏和热交换现象所引起的轴功损失,并将其细分为不可逆传热、绝热节流、不同温度流体混合以及外泄漏等4种不同性质的火用损失形式。在依据热力学第一定律和质量连续定律建立的压缩机模型基础上,对在压缩机工作过程中通过4种形式损耗的火用值分别进行了计算和讨论。分析结果表明,在压缩机工作转速提高过程中,由于泄漏量和换热量减少,火用耗散出现明显下降。

An exergy method was used to study usage efficiency of single screw compressor＇s shaft, power in the fuel cell vehicle. As the shaft power wastage on both leakage and heat exchange was analyzed, it could be further classified into four kinds, namely irreversible heat exchange, adiabatic throttling of gas, mixing of two flows and leakage to environment. On the basis of single screw compressor＇s mathematical model which was established according to the first law and mass balance, the exer gy loss by the four kinds mentioned above were calculated and the discussion was presented. The analysis results indicate the exergy loss decreases when the leakage and heat exchange decrease which is caused by the increase of the compressor＇s rotating speed.