基于Kriging代理模型液压锥阀抗空化结构优化研究

Optimization Based on Kriging Agent Model for Anti-cavitation Structure of Hydraulic Poppet Valve

空化是液压锥阀运行时造成振动及噪声的重要因素,其影响原因颇为复杂。针对水液压锥阀内空化问题,利用Fluent中混合模型(Mixture)及标准k-ε湍流模型,对不同阀芯锥角的锥阀进行计算流体动力学(CFD)分析,发现锥角和开度对锥阀内的空化程度有直接影响。将阀芯锥面改为2个不同锥角的锥面,对阀芯结构参数作5水平全因子实验设计,分析出125个模型的气体体积分数,以平均气体体积分数为空化优化设计目标,建立平均气体体积分数与阀芯结构参数之间的Kriging模型,然后采用遗传算法对此模型进行寻优,得到最优的锥阀结构。优化后的锥阀结构对空化有一定抑制效果。

Cavitation is an important factor in vibration and noise of a hydraulic poppet valve,and its influencing factors are quite complicated. According to the problem of internal cavitation in water hydraulic poppet valve,the CFD analysis of poppet valve with different cone angles is carried out by a fluent mixture model and a standard k-epsilon turbulence model. It is found that cone angle and opening degree have a direct influence on cavitation degree in poppet valve. The conical surface of valve core is changed into two conical surfaces with different cone angles,and the valve core structure parameters are used to design a 5 level whole factor experiment. We analyze gas volume fractions of 125 models,and take the average gas volume fraction as the optimization design target of cavitation. A kriging model is established between the average gas volume fraction and spool structure parameters.Then the optimal poppet valve structure is obtained by genetic algorithm. The optimized poppet valve structure has a certain inhibitory effect on cavitation.