增压柴油机内冷油腔活塞结构分析及评价

以增压柴油机振荡内冷却油腔活塞非对称性结构为研究对象,构建了全活塞-活塞销-连杆小头的有限元接触模型,分析了活塞工作条件下的导热耦合关系。确定了当量换热边界条件;进行了在机械-热负荷联合作用下的结构应力及变形分析;为直观反映温度因素对活塞结构强度的影响,提出了对结构应力合理表述的应力-温度散点图评价方法;在此基础上对原有的活塞结构进行了改进。

Structural Analysis and Evaluation of a Turbo Charged Diesel Engine Piston with an Inner Oscillating-Oil-Cooling Channel

A FEM is used to analyze the structural strength of a turbo charged diesel enginepiston withan cscillating-oil-cooling channel by modeling the whole assembly of piston, gudgeon pin and small-eng of connecting rod.A set of convectionboundary conditions is explored for describing the heat transfer characteristics ol the piston, and equivalent coefficients of heat transfer are determined. Then temperature, stress, and deformation of the piston under the coupled action of mecbanical and thermal load are calculated and analyzed. Further, an original stress-temperature graph method tructural evaluation using the stress-temperature point clouds is put forward in order to more intuitionally and reasonably reflect the effect of temperature on piston strength in structural evaluation. Finally,design improvements are achieved based on the structural analysis and evaluation of the piston.