中文摘要：

引言 喷射器是一种应用非常广泛的流体机械，它利用工作流体的射流来实现能量转化。喷射器以其结构简单、造价低廉、操作和维修方便等特点，广泛用于抽除气体、余热回收、混合加热等领域。

英文摘要：

An adjustable ejector with a spindle in the nozzle was developed for a wider adjustment range. An experimental study was carried out on the performance of the adjustable ejector. To change the spindle position axially the nozzle throat sectional area could be changed. The ejector flow parameters, such as flow rate, pressure and entrainment ratio, at different spindle positions were measured. The results showed that the adjustable ejector could be used in a wider range of fluid flow rate. When the throat area was reduced, the ultimate discharge pressure would be lower but the entrainment ratio would increase greatly.