双喷嘴射流泵基本特性方程及其性能研究
Basic characteristic equations and performance of dual nozzles jet pump
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摘要: 以射流泵理论和能量守恒定律为基础,采用洛伦兹流体混合损失模型,推导出新型双喷嘴射流泵的基本特性方程。当流速比V=1时,射流泵的理想效率为100%;当0Kj>Ks,得到了射流泵完整的特性方程和实际特性曲线,结果表明:随着面积比R的增大,压力比P增大,但射流泵的工作区间缩小,高效区的位置左移;射流泵最高效率随流量比M1呈现先增大后减小的趋势,而压力比P则是一直减小,符合能量守恒规律;实验样机的最优面积比Ropt为0.30,最优流量比Mopt为1.04,新型射流泵的效率最大值为22.57%。Abstract: Based on the theory of jet pump and the law of energy conservation,the basic characteristic equations of a novel dual nozzle jet pump was derived by employing Lorenz mixed loss model. When the velocity ratio V = 1,the theo- retical ideal efficiency of jet pump is 100% ;when 0Kj >Ks . The jet pump basic characteristic equations were completed,and the real basic characteristic curve plotting was drawn. The results show that the pressure ratio P increases while the area ratio R increases,whereas the working range decreases,and the efficient range of jet pump moves left on the curve plotting. The peak efficiency increases at first then decreases with the flow rate ratio M1 ,nonetheless the pressure ratio P decreases with M1 con- stantly. This phenomenon is in accordance with the law of energy conservation. According to the experimental data of the prototype,the optimal area ratio Ropt is 0. 30,the optimal flow rate ratio Mopt is 1. 04,and the peak efficiency is 22. 57% .