探针型线对汽车空调用二氧化碳可调喷射器性能影响的仿真研究

Simulation Study of the Effect of Probe Profiles on the Performance of CO_(2) Adjustable Ejectors for Automotive Air Conditioning

为获得合适的汽车空调用CO_(2)可调喷射器调节探针的外型曲线,基于均相平衡模型(HEM)提出了直线型、下凹型和上凸型3种探针方案,并借助计算流体力学(CFD)工具分析了探针移动过程中喷射器流量和引射比的变化情况,对比了3种探针方案可调喷射器的性能差异,结果表明:喉部处探针半径较小时,随着喉部处探针半径增大,各方案喷射器引射比均因一次流流量的减小缓慢增大,当喉部处探针半径超过高效调节半径时,各方案喷射器引射比急剧下降,直至无法引射;相较于其他2种探针方案,下凹型探针方案在高效工作区内引射比较大,综合性能更强。

In order to obtain a suitable shape curve of the CO_(2) adjustable ejector regulating probe for automobile air conditioning,this paper proposed three kinds of probe schemes including linear,concave and convex probe based on the Homogeneous Equilibrium Model(HEM),and the analyzed changes of the ejector flow rate and elicitation ratio in the process of probe movement with the aid of the Computational Fluid Dynamics(CFD) tool,and compared the differences in the performance of the adjustable ejector with the three kinds of probe schemes.The results show that:When the probe radius at the throat is small,with the increase of the probe radius at the throat,the entrainment ratios of the ejector of each scheme increase slowly due to the decrease of the primary flow rate,and when the probe radius at the throat exceeds the high efficiency adjustment radius,the entrainment ratios of the ejector of each scheme decrease dramatically until they can't be induced;compared to the other 2 probe schemes,the concave probe scheme has a larger entrainment ratio within the high efficiency working area,and it has a stronger overall performance.