高原环境下柴油机冷却系统性能仿真

利用GT-suite软件建立了柴油机工作过程模型和冷却系统模型并进行直接耦合,通过高原模拟台架试验验证了模型的正确性,进而研究了不同海拔外特性工况下柴油机及其冷却系统性能的变化规律。结果表明:海拔每升高1 000m,柴油机出口水温平均升高5.01%,散热量平均减小6.25%,风扇质量流量平均减小11.20%,柴油机功率平均减小3.55%,燃油消耗率平均增加4.67%;该装甲车辆在海拔1 000~2 600 m低转速区和海拔2 600m以上必须降负荷或者提高冷却系统散热能力后使用。最后以柴油机出口水温不超过报警值为目标,计算得到了柴油机最大允许负荷和风扇最小体积流量增幅MAP图,为高原环境下柴油机及其冷却系统匹配和改进提供了参考。

Simulation of Diesel Engine Cooling System in Plateau Environment

The working process model and cooling system model for diesel engine were established and directly coupled with GT-suite software .The effectiveness of model was verified by the plateau simulation bench test ,and then the variation laws of diesel engine and its cooling system performance under external characteristic working conditions at different altitudes were studied .The results show that the water temperature at the outlet and the fuel consumption rate increases by 5 .01% and 4 .67%on average and the heat dissipation ,the fan mass flow and the engine power decreases by 6 .25%,11 .20% and 3 .55% on aver-age for each 1 000 m elevation of altitude .The armored vehicle cannot work unless the load decreases or the cooling capacity of cooling system increases at low speed between 1 000 m and 2 600 m and the whole speed range above 2 600 m .Finally ,the MAP of engine maximum allowable load and fan minimum volume flow rate increase are calculated and determined based on the alarm limit of outlet water temperature ,which provides a reference for the matching and optimization of diesel engine and cool-ing system in the plateau environment .