【摘要】 针对某款四缸柴油机搭建了活塞动力学模型。通过计算活塞温度场,分别得出活塞在温度应力与缸内燃气压力下的变形,同时计算得出缸孔在螺栓预紧力与热载荷下的变形量,得到热机耦合下的活塞型线与缸孔型线。在此基础上对缸孔-活塞系统进行优化设计,在额定工况(3 200 r/min,110 kW)下摩擦损失功率(P_f)降低了8.13%,活塞敲击动能降低38.6%,在最大转矩点工况下各性能也得到改善。更多还原

【Abstract】 Research on a four cylinder diesel engine, a kinematic model for the piston was built. By calculating the piston temperature field, the piston deforming under temperature stress and gas pressure were obtained. At the same time, the deformation of cylinder bore is calculated under the condition of bolt preload and thermal loads, the piston line and the cylinder pass line under the thermo-mechanical coupling were worked out. On this basis, the optimization design of bore-piston system was completed, the engine gets 8.13% reduce on friction loss power(P_f) and 38.6% reduce on slap energy at rated operating condition(3 200 r/min,110 kW), the performance of the engine at maximum torque point is also improved.更多还原