米雪1,刘晓日1,周晶晶2,黎明1,魏石峰1,李国祥3
（1.河北工业大学 能源与环境工程学院，天津 300401；2.天津职业大学 汽车工程学院，天津 300410；3. 山东大学 能源与动力工程学院，山东 济南 250061）
摘要：本文以ZS1100单缸水冷柴油机为研究对象,建立了一种适用于柴油机的缸内近壁面传热模型,模型保留Woschni关系式的形式,其中特征长度、特征压力、特征速度和特征温度的数值取燃烧室内三维瞬态仿真计算中贴近燃烧室结构壁面的第一层网格的数据,所以该模型具有非稳态时间特性和空间局部特性,从而能够反映内燃机缸内的非稳态局部传热情况。新模型中的待定系数使用缸盖底面测点的热流密度的试验数据确定。新模型计算时间增加很少,适用于工程计算。
关键词：缸内传热模型; 瞬态; 局部传热; Woschni关系式; 特征参数;
Abstract: Taking ZS1100 single cylinder diesel engine as research object, an in-cylinder near wall heat transfer model for diesel engine is proposed. The new model keeps the form of Woschni correlation formula. Characteristic length, pressure, velocity and temperature are obtained from the data of the first layer mesh grids adjacent to the combustion chamber that are achieved from in-cylinder simulation. The new model has both time and spatial characteristics and thus is able to reflect unsteady state local heat transfer. The coefficients of the new model are determined by experimental heat flux data of the bottom of cylinder head. The new model requires only small amount of extra CPU time, and thus is suitable for engineering calculation.
Key Words: In-Cylinder Heat Transfer Model; Transient State; Local Heat Transfer; Woschni Correlation Formula; Characteristic Parameters
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