喷嘴直径对喷射器性能的影响分析

利用二维轴对称,真实气体模型对喷射式制冷空调系统的喷射器进行CFD计算。真实气体模型占用较多的计算机资源,但它的计算结果更加真实。计算的目的在于得到在不同喷嘴直径条件下喷射器性能的变化和制冷系统性能的变化情况。在计算工况条件下,存在一最优的喷嘴直径Dn*(5mm),使得此时的喷射系数和系统COP最大。当Dn>Dn*时,喷射系数和COP随着喷嘴直径的增加而减少;当Dn

Discuss of vapor ejector on different nozzle diameter

The 2D axisymmetric,real gas model was developed to calculate the ejector in the ejector cooling system.The calculation of the real gas model occupied more computer resources,but its result could be more authentic.The aim of the prediction is to obtain the ejector performance and COP in different ejector nozzle diameter.There was an optimum nozzle diameter Dn*(5mm) with the giving operating condition and the other geometry parameters.When Dn=Dn*,the entrainment ratio reached the maximum value;when DnDn*,the entrainment ratio also decreased but the trend became more gently.The change of the primary and secondary mass flow was caused by the change of shock wave;the change of shock wave was the result of the change of nozzle diameter.