基于正交试验设计的气缸套变形研究

Study on Cylinder Liner Deformation Based on Orthogonal Test Design

应用正交试验设计方法考察设计因素对柴油机气缸套变形的影响趋势和相互关系.选取螺栓预紧力、螺栓与气缸中心距离和螺栓孔下沉量作为考察因素,建立了气缸盖、气缸垫、气缸套和机体的组合有限元模型。基于正交试验设计法设计了16组计算方案,通过有限元分析,得出气缸套3个截面的变形和最小主应力结果,同时得到了以上3个因素对气缸套变形及受力的影响规律。结果表明,降低气缸套变形和最小主应力为优化目标时,选取合适的螺栓孔下沉量是最重要的优化目标;在保证气缸密封的前提下,适当降低螺栓预紧力;螺栓与气缸中心距离对优化目标影响最不明显。

The influence of design factors on cylinder liner deformations and relationship among them are investigated. The bolt preload force,distance of the bolt and cylinder bore center and sinkage of the bolt are selected as the investigation factors. Finite element model of the assembly consisting of cylinder head,cylinder gasket,cylinder liner and block is set up. The cylinder linear deformation and minimum principal stress of the model are calculated through 16 computational schemes based on orthogonal test design theory. Influence of the above three factors on the three sections deformation of cylinder liner and minimum principal stress are analyzed according to the calculation results. Calculation results show that choosing appropriate sinkage of the bolt is the most important factor to decrease the deformations and stress in cylinder liner,decreasing the bolt preload force is the second factor on assuring seal condition,changing distance of the bolt and cylinder bore center has relatively less influence on the change of deformations and stress in cylinder liner.