蒸汽喷射制冷系统喷射器工作特性的实验研究

为确定喷射器的工作特性,评估数值模型计算精度,完善喷射泵抽气理论,构建了小型水蒸气喷射制冷实验系统.实验研究了水蒸气喷射泵性能与工作蒸汽压力、被抽蒸汽压力、背压的关系.实验结果表明,随着工作蒸汽压力的上升,被抽蒸汽流量和引射系数均呈先升高,达到最大值后下降的趋势.随着被抽蒸汽压力的升高,被抽蒸汽流量和喷射器引射系数均增加.在一定背压范围内,喷射器引射系数保持不变,当超过临界背压后,引射系数急剧下降.研究结果对于了解喷射泵抽气特性、改进喷射泵结构和性能优化有参考价值.

Experimental Investigation of Operating Characteristics of Ejector in Steam Jet Refrigeration System

To determine the operating characteristics of ejector， evaluate the numerical model calculation accuracy and improve the ejector pump theory， an experimental system of small steam jet refrigeration was set up. The relationships between the steam jet pump performance and working steam pressure， suction pressure， the back pressure of the ejector were studied by using experimental method. The experimental results show that the secondary fluid flow rate and ejector coefficient (entrainment ratio， ER) increase firstly to the maximum and then decrease gradually with increasing the working steam pressure. With increasing suction pressure， the secondary fluid flow rate and the ER increase. The ER keeps a constant value in a certain range of back pressure and declines sharply when back pressure is bigger than the critical back pressure. It is important to understand the pumping characteristic of steam jet pump deeply based on the experimental research， and the experimental data can be used to optimize steam jet pump’s structure.