基于正交试验的曳力模型改进研究

Study on improvement of drag model based on orthogonal test

通过正交试验法向经典曳力模型中添加颗粒拟温度项以改进曳力模型,并对比改进模型BVKM-1和BVKM-2与原始模型在鼓泡流化床算例中的表现.结果表明:正交试验法参数寻优可大幅减小工作量,适合CFD-DEM曳力模型改进研究.通过向曳力模型以多项式形式添加颗粒拟温度项,改进模型的时均结果得到了显著改善.在y=35 mm截面x=1.01 mm处,BVKM-2模型与实验值的相对误差仅为14.03%,而原始BVK模型的相对误差高达93.73%.BVKM-2模型的表现优于BVKM-1,也更接近原始BVK模型.BVKM-1和BVKM-2形式类似,参数略有差别,但模拟结果差别较大,这说明向曳力模型以多项式形式添加颗粒拟温度项时,模拟结果对多项式的参数非常敏感.

The particle pseudo-temperature term was added to the classic drag model through the orthogonal experiment method to improve the drag model,and the performance of the improved model and the original model in a bubbling fluidized bed example was compared.The research results show that the orthogonal experimental method parameter optimization can significantly reduce the workload and is suitable for CFD-DEM drag model improvement research.By adding a particle pseudo-temperature term in polynomial form to the drag model,the time-averaged results of BVKM-1 and BVKM-2 are significantly improved.At y=35 mm section x=1.01 mm,the relative error between the BVKM-2 model and the experimental value is only 14.03%,while the relative error of the original BVK model is as high as 93.73%.The BVKM-2 model performs better than BVKM-1 and is closer to the original BVK model.BVKM-1 and BVKM-2 are similar in form,with slightly different parameters,but the simulation results are quite different.This shows that when adding particle pseudo-temperature terms in the form of polynomials to the drag model,the simulation results will be very sensitive to the parameters of the polynomial.