低温对涡轴发动机起动性能影响的试验与分析

为研究低温对涡轴发动机起动性能的影响,对国军标的适用与裁剪进行了讨论,开展了低温起动试验,试验以滑油箱内的滑油温度达到-34 ℃算起,冷浸4 h后进行起动,分析了低温起动过程的阻力矩、剩余扭矩、点火性能和温升效应对起动性能的影响。结果表明:-34 ℃条件下的初始阻力矩是25 ℃条件下的2.25倍,至点火转速附件阻力矩降低为1.53倍；温度越低,点火边界对应的索尔太平均直径(SMD)越小,燃烧室点火边界越窄；温升效应对低温起动性能的影响显著,考虑温升效应的起动时间延长约25%。热空气加温和起动滑油断油可以降低起动初始阻力矩,改善点火性能,从而提高了低温起动性能。研究结论对同类发动机开展低温起动试验、起动供油规律优化及相关研究提供了参考。 

Test and analysis on influences of low temperature on starting performance of turboshaft engine

To investigate the influences of low temperature on turboshaft engine starting performance, application and tailoring of national military standard were discussed. Low temperature starting tests were conducted at -34 ℃ based on oil temperature in four-hour cold soak process. The influences of resistance torque, residual torque, ignition performance and warm-up effect on cold starting performance were investigated. Results showed that, initial resistance torque under -34 ℃ was 2.25 times of 25 ℃ and 1.53 times near the ignition. The Sauter mean diameter (SMD) was smaller for ignition boundary in the lower temperature. The influences of warm-up effect on low temperature starting was significant and the start-up time with warm-up was extended by about 25%. Heating up on the engine and cutting off oil lubricating can reduce initial resistance torque and improve the ignition performance, thus improving the low temperature starting performance. The conclusion provides a reference for the low temperature starting test, starting fuel supply control law optimization and research of similar engines.