冷却液温度对柴油机热功转换效率的影响

Influence of Coolant Temperature on Diesel Engine Heat and Power Conversion Efficiency

以热力学第一定律为基础,分析了柴油机热功转换的机制,在此基础上建立了基于GT-Suite软件的仿真模型,实现了冷却系统与发动机的耦合仿真。设计并进行了DEUTZ TCD8V2015型柴油机的热平衡试验,对仿真模型进行了校核。利用所建立的分析手段,研究了冷却液温度变化对柴油机热功转换过程的影响,得出了发动机性能及缸内传热随冷却液温度的变化趋势。结果表明柴油机中小负荷时冷却液温度变化对热功转换效率影响较大,冷却液温度每升高20℃,热功转换效率增加2%～3%。

In order to study the heat and power conversion efficiency of diesel engine with different coolant temperatures, an engine and cooling system co-simulation model was built based on the first law of thermodynamics. This model was established by GT- Suite software to simulate the interaction of engine and cooling system performance parameters. A heat balance experiment of DEUTZ TCD8V2015 diesel engine was designed and executed, and the model was verified by the experimental data. Based on that, the coolant temperature influence of conversion efficiency was researched on the modified model, some rules and tends between the coolant temperature and the heat transfer in the cylinder were obtained. Results indicated that the power conversion efficiency would increase by 2% - 3% with coolant temperature raised by 20℃ on 30% load of diesel engine.