多弧槽球面配流副润滑特性分析与多目标优化

为改善锥形缸体球面配流副油膜润滑特性，提出一种多弧槽球面配流副结构，并采用遗传算法对多弧槽球面配流结构进行多目标优化。首先，对多弧槽球面配流副进行理论建模，采用有限容积法对油膜压力控制方程进行离散化，利用环形三对角矩阵算法(CTDMA)求解球面配流副压力分布；然后，对多弧槽球面配流副承载特性进行仿真，分析球面配流副不同弧槽结构下的油膜厚度分布及压力分布规律；最后，以缸体倾角、泄漏量和摩擦转矩为优化目标，利用多目标遗传算法优化多弧槽球面配流副的结构参数。结果表明：多弧槽结构可提升球面配流副油膜承载能力，弧槽结构最小膜厚下降3.1%～4.0%,弧槽结构最大压力显著提高，最大增幅为16.3%;同时可有效降低泄漏量、摩擦转矩，优化后综合目标性能提升10.5%,缸体倾角、泄漏量和摩擦转矩分别下降5.1%、8.1%和5.9%,有效提升了球面配流副润滑性能。

Analysis and Multi-objective Optimization of Oil Film Lubrication Characteristics of Multi-arc Groove Spherical Valve-plate Structure

In order to improve the oil film lubrication characteristics of the spherical valve-plate pair with conical cylinder block, a multi-arc groove spherical valve-plate pair structure was proposed, and the genetic algorithm was used to optimize the multi-objective structure of the multi-arc groove spherical valve-plate pair. Firstly, the multi-arc groove valve-plate pair was theoretically modeled, the finite volume method was used to discretize the oil film pressure control equation and the circular tridiagonal matrix algorithm(CTDMA) was used to solve the pressure distribution of the spherical valve-plate pair. Secondly, the load-bearing characteristics of the multi-arc groove spherical valve-plate pair were simulated, the oil film thickness distribution and oil film pressure distribution of the spherical valve-plate pair with different arc groove structures were analyzed. Thirdly, the cylinder overturning angle, leakage loss and friction torque were used as the optimization objectives, the multi-objective genetic algorithm was used to optimize the structural parameters of the multi arc groove spherical valve-plate pair. The results showed that the multi-arc groove structure can improve the load-bearing capacity of the oil film of the spherical valve-plate pair, the minimum oil film thickness decrease for the arc groove structure ranged from 3.1% to 4.0%, and the maximum pressure increase significantly for the arc groove structure was 16.3%;while effectively reducing the leakage loss and friction torque. After optimization, the overall target performance was improved by 10.5%, cylinder overturning angle, leakage loss and friction torque were reduced by 5.1%, 8.1% and 5.9%, respectively, which effectively improved the lubrication performance of the spherical valve-plate pair.