航空活塞发动机稳压箱温度影响因素及高空特性研究

Research on the Influencing Factors and High Altitude Characteristics of Surge Tank Temperature for Aviation Piston Engine

针对某型航空活塞发动机中冷系统,建立了系统的传热数学模型.通过与实验数据相对比可知,中冷器冷侧出口温度、热侧出口温度模拟结果误差均在1.5%以内,明确了本文构建仿真模型可行且可靠.进而,利用该模型研究了中冷系统空气速度、环境温度、增压比、进气流量等因素对稳压箱温度的影响,分析了航空活塞发动机中冷系统的高度特性.结果表明:稳压箱温度随着空气速度的增加而降低,随着环境温度、增压比及进气流量的增加而上升.稳压箱温度对增压比的敏感度最大,对环境温度的敏感度最低,对进气流量及空气速度的敏感度介于二者之间.对于所研究的航空发动机中冷系统,最高稳压箱温度及中冷系统最大换热量均出现在临界增压高度,在海平面温度为50℃的条件下,二者的值分别为82.4℃、11.5 kW.

Aiming at the intercooling system of an aero piston engine,the heat transfer mathematical model of the system was established.By comparing the simulation results with experimental data,it is found that the error in the simulation results of the cold side outlet temperature and hot side outlet temperature of the intercooler is within 1.5%,confirming the feasibility and reliability of the simulation model constructed in this paper.Furthermore,using the simulation model,the effects of air velocity,ambient temperature,supercharging ratio,intake air flow rate on the temperature of the surge tank were studied,and the altitude characteristics of the intercooling system of the aviation piston engine were analysed.The results show that,the temperature of the surge tank decreases with the increase of air speed,and increases with the increasing ambient temperature,supercharging ratio and intake air flow.The temperature of the surge tank is most sensitive to the supercharging ratio,and least sensitive the ambient temperature,with sensitivity to intake flow and air speed falling between the two.For the intercooling system of the aero engine,the maximum temperature of the surge tank and the maximum heat transfer of the intercooling system appear at the critical supercharging height,which are 82.4℃and 11.5kw under the condition of sea level temperature of 50℃,respectively.