Piston secondary motion not only influences the side knocking of piston and frictional loss, but also influence the in-cylinder oil consumption and gas blow-by. An inline four-cylinder common rail diesel engine was chosen as the research object. Dynamic simulation model of piston assembly was built based on the piston and cylinder liner temperature field test. The impacts of pinhole offset, liner clearance and piston skirt ovality on piston secondary motion were researched. Based on the surface response method, the influence of multiple factors on friction power loss and slapping energy is estimated. The results indicate that: in-cylinder stress condition of piston will change with its structural parameters, then the secondary motion of piston will be affected as a result. Pinhole offset, liner clearance, piston skirt ovality and the interaction of the latter two all have significant effects on the friction power loss, while the slapping energy is significantly affected by liner clearance. Therefore, the parameters can be designed based on the significance level to optimize the secondary motion characteristics of the piston.

活塞二次运动不仅影响活塞的侧爆和摩擦损失，而且影响缸内油耗和窜气。选择一台直列四缸共轨柴油机作为研究对象。基于活塞和缸套温度场试验建立活塞总成动态仿真模型。研究了针孔偏移、缸套间隙和活塞裙椭圆度对活塞二次运动的影响。基于表面响应法，估计了多种因素对摩擦功率损失和拍打能量的影响。结果表明：活塞的缸内应力状态会随着其结构参数的变化而变化，进而影响活塞的二次运动。针孔偏移、衬垫间隙、活塞裙椭圆度和后两者的相互作用都对摩擦功率损失有显着影响，而拍击能量受缸套间隙的影响显着。因此，可以根据显着性水平设计参数，以优化活塞的二次运动特性。