温度对飞机燃油射流泵工作特性影响

建立了射流泵数学模型，采用数值计算方法对其工作特性进行了模拟，搭建了实验台，采用RP-3燃油，通过实验数据验证了模型的正确性.在此基础上，分别选择了RP-3和JET-A两种燃油，计算了从-40℃~40℃温度下，不同操作压力对射流泵流量比的影响.结果表明:燃油温度高于0℃时，温度对射流泵工作特性影响并不明显，随着温度的降低，射流泵性能与标准温度下（20℃）偏差越来越大，且压比越高此偏差越明显.当温度高于0℃时，采用RP-3和JET-A燃油性能相差不大，RP-3燃油性能略优于JET-A燃油，但是在低温下，RP-3燃油性能远高于JET-A燃油.因此当燃油温度较低且压比较高时，必须充分考虑温度对射流泵特性的影响. 

Effect on working characteristic of fuel injection pump in aircrafts of temperature

A mathematical model of the injection pump was set up and its working characteristic was simulated using numerical computation method, the experiment apparatus was constructed and RP-3 fuel was adopted as the working fluid to verify the validity of this model. The flow ratio under various operating pressures was calculated from -40 degree to 40 degree by employing RP-3 fuel and JET-A fuel as working fluids, respectively. Result shows that if the fuel''s temperature is above 0 degree, the effect of the fuel temperature on the working characteristic of injection pumps can be ignored. However, with the decrease of the temperature, the deviation of the performance with that at standard temperature(20 degree) increases definitely, especially the pressure ratio is high. When the temperature is above 0 degree, the performance of injection pump using RP-3 fuel is slightly better than that using JET-A fuel, but if the temperature is extremely low, the performance using RP-3 fuel is much better than that using JET-A fuel. It can be concluded that when the temperature is low and the pressure ratio is high, the effect caused by the temperature on the performance of injection pump should be considered carefully.