关键词: 喷射器, 喉嘴距, 引射比, 临界背压

Abstract:

The primary nozzle exit position (NXP) is one of the important geometrical factors affecting the ejector performance. In the present study, the ejector performance was investigated experimentally for getting the changing rules of the ejector performance with different NXPs and working conditions. The results show that the NXP has little influence on the critical pressure, but has obvious influence on entrainment ratio. The entrainment ratio first increases and then decreases with NXP. Both the two-phase and single-phase ejectors have their respective optimum NXPs. The optimum NXP increases with the water mass flowrate of the low-pressure fluent. The optimum NXP is 2.8 mm in single-phase operation while it becomes 3.6 mm when the water mass flowrate of the low-pressure fluent is 0.07 kg/min.

Key words: ejector, NXP, entrainment ratio, critical back pressure