多喷管引射器的性能分析

应用气体动力学原理，推导了超音速多喷管引射器引射系数的计算公式。针对某型号发动机进气防砂滤清砂引射器，进行了性能特性计算和试验。结果表明，随着主次流压比降低、温度比增大，混合管与主喷管截面积比增大以及混合管长径比增大，引射系数均随着增大。在相同工况条件下，Ｌｍ／Ｄｍ＜７．０时，多喷管引射系数比当量收缩单喷管的引射系数大，且Ｌｍ／Ｄｍ越小，两者相差越大。理论计算和测试结果符合良好

Performance Analysis of a Multi Nozzle Ejector

A formula for calculating the ratio of secondary flowrate to primary flowrate of the supersonic multi nozzle ejector is deduced by using aerodynamics.The performance of an ejector of inlet gas sand separator in a certain type of the aeroengine is calculated and tested .Results of the calculation show that the flowrate ratio of secondary flow to primary flow increases with the decrease of P po /P so and the increases of T po /T so , A m/ A t and L m/ D m. The flowrate ratio of the multi nozzle ejector is greater than that of the equivalent convergent single nozzle ejector under the same conditions with L m /D m<7.0, and the smaller L m/ D m, the greater the difference between them.Good agreement between theoretical analysis and experiment is obtained.