摘要
建立了冷却系统传热模型和边界条件计算模型。以缸内燃气压力和温度试验数据为基础,利用经验公式计算了气缸体内壁与燃气、外部与冷却空气间的传热边界条件。以气缸体温度场计算为切入点对发动机热状态进行研究,计算并分析了不同飞行高度下气缸体的温度分布;研究了螺旋桨转速对气缸体温度的影响;同时还计算了最大功率工况下保持热状态稳定需要的螺旋桨转速;试验测取了不同高度时的气缸体特征点温度。计算和试验结果表明:在最大功率工况下,螺旋桨转速不变时,随着飞行高度的增加发动机热状态逐渐升高;同一飞行高度下,螺旋桨转速越高,发动机热状态越低;调节螺旋桨转速能够使气缸体温度稳定在某一范围内;试验与仿真结果的误差小于5%,满足工程需要。
Cooling system heat transfer model and boundary condition computation model were founded to calculate engine thermal state. Based on the measured experimentally gas pressure and temperature, the heat transfer boundary conditions between cylinder wall and high-temperature gas, cylinder external surface and cooling air were calculated by using empirical formula. Taking cylinder temperature field calculation as the entry point, cylinder block temperature distributions at different flying heights were simulated and analyzed the effect of propeller speed on cylinder block temperature was researched the propeller speed required to keep the steady thermal state in max. power condition was computed, and the temperatures of cylinder block feature points were measured at different heights. Calculation and test results show that in max. power condition,engine thermal state enhances gradually with flying height rising while propeller speed is constant the higher the propeller speed is, the lower the engine thermal state will be at the same flying height. The cylinder block temperature can be maintained in a certain range by adjusting propeller speed. The error between calculation and test results is less than 5 %,satisfying the engineering need.
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2014年第1期35-40,共6页
Chinese Internal Combustion Engine Engineering
基金
装备部预研项目(40109/02010101)
关键词
内燃机
航空
风冷活塞式发动机
冷却系统
传热模型
热状态
IC engine
aviation
air-cooled piston engine cooling system
heat transfer model
thermal state
