采用Kriging代理模型的蜗壳优化设计

摘要

An optimization design was developed for volute in order to address the impact on the volute performance resulting from circumferential variation in the cross sectional area distribution. And a Matlab⁃based aerodynamic optimization program was developed for minimizing the total pressure loss. The optimization of average coefficient of total pressure loss of the flow in volute was achieved by changing the geometric construction. With two circumferential cross section areas as controlling points which were then adjusted with one parameter, the calculation with commercial CFD software led to a numerical value. This optimization program adopting the Kirging model with both precision and calculation cost taken into consideration, finally resulted in an optimal cross⁃sectional area distribution aiming at the minimum total pressure loss coefficient. By comparison with prototype, the optimized volute has an improved performance.%针对蜗壳周向截面面积分布发生变化对蜗壳性能产生影响的问题，进行了蜗壳的优化设计。为了减小蜗壳的总压损失，开发了基于Matlab平台的气动优化程序。通过改变蜗壳的几何结构，使得蜗壳的流量平均总压损失系数得到优化。蜗壳周向的两个截面的面积被设定为控制点，并用一个参数进行调整。采用商用CFD软件进行计算，得到数值计算结果。程序中采用Kriging代理模型以兼顾精度和计算成本的要求。最后得到以最小总压损失系数为目标的蜗壳最优截面面积分布。优化后的蜗壳在性能上相比原型有了一定改进。