某航空活塞发动机回火试验

为解决某航空活塞发动机要取得适航型号合格证(TC)须按CCAR-33部《航空发动机适航标准》第33.51条进行回火试验的问题,通过对单缸发动机回火试验的研究,提出了采用光电信号进行发动机回火检测的测量方法.试验验证表明:光电检测方法能够有效地检测到发动机回火现象.在此基础上,通过试验确定了调节燃油伺服器的贫富油操纵杆逐渐调贫发动机的燃油流量来诱导发动机回火的试验方法.回火试验结果表明:所测活塞发动机在其整个工作状态下存在回火倾向,但在人工诱导57次回火后,发动机状况良好,满足适航认证的要求. 

Backfire tests of an aircraft piston engine

In order to solve the problem of one aircraft piston engine that the backfire test must be conducted to acquire the airworthiness type certificate (TC) pursuant to article 33.51 of part CCAR-33 “Airworthiness standard of aircraft piston engine”,a new test method was proposed based on the photoelectric signals through the study on single-cylinder engine.The experiments showed that the proposed method can well detect the backfire.Based on the above research,the inducing backfire method was conducted through reducing the flow rate of fuel by operating lean/rich joystick.The experiments on the tested engine show the engine is tendency to backfire in its operating conditions and the engine works well after 57 times artificial induction backfire on the tested engine.The tested engine meets the requirements of airworthiness certification.