以某柴油机涡轮增压器的压气机为例,基于多重子结构技术,建立了增压器压气机叶轮、轴套和轴的三维整体有摩擦弹性接触的计算模型,采用有限元参数二次规划法,对其进行有限元分析。针对不同的过盈量、摩擦因数、轴套壁厚和转速进行计算,获得了叶轮、轴套与轴之间接触应力的分布规律。分析表明,随着叶轮与轴套间过盈量的增大,轴套的外表面与内表面的接触应力是线性增大的,而且内表面的接触应力增加较为迅速,这对于确定合理过盈量和改进设计具有参考意义。
Based on the FE parametric quadratic programming (PQP) method, the stress distribu tion of 3-D frictional contact problem of impeller-shaft sleeve-shaft assembly was analyzed. A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference -fit loading was used for the numerical analysis. To save the time cost in the numerical computation, multi--substructural technique was adopted for the :structural modeling. The effects of fit tolerance, coefficient of friction, the wall thickness of shaft sleeve, rotational speed and the contact stress distri bution on the mating surfaces were discussed in the numerical computation. It is found that nonuni- form initial amount of interference in the structural design will avoid relative displacement generated and ensure uniformity of the contact stress. The study provides an effective approach which achieves more reliable interference-fitted connections and more precise assembly while eliminating the need for using high-precision and high-cost manufacturing methods.