平衡孔板孔数和分布研究

Study on the hole number and distribution of a balanced orifice plate

采用数值模拟方法研究平衡孔板平衡孔数量和圆心圆直径的最佳取值。以管径D=100 mm、等效开孔直径比β=0.6工况为例,介绍了获得最佳平衡孔数量和圆心圆直径比的方法和过程。取定圆心圆直径比情况下(K=0.67),对比不同平衡孔数量时流出系数、压力损失和动量差等指标,得到最佳开孔数量为N=10;取定平衡孔数量情况下(N=10),对比不同圆心圆直径比时上述评判指标,得到最佳圆心圆直径比为K=0.67。文中给出了DN50~DN1000五种管道规格和6个等效开孔直径比各种工况组合的最佳结构参数,平衡孔最佳开孔数量为8或10个,最佳圆心圆直径比K的取值在0.64~0.73之间(多数情况下取值在0.66~0.70之间)。文中提出了动量差概念用于进行平衡孔性能的评判,对比结果表明,以动量差ΔM达到最小值作为某个结构参数取得最佳的辅助依据是可行的。研究结果对于平衡孔板结构设计具有参考价值。

Numerical simulation is used to study the optimal values of the balancing hole number and the diameter of hole opening circle of a balanced orifice plate.It introduces the method and procedure to obtain optimal balancing hole number and circle diameter ratio are presented for the case of pipe diameter D=100 mm and equivalent diameter ratio ofβ=0.6.It is found that the optimal hole number is N=10,after comparing the discharge coefficient,pressure loss and momentum difference for different hole numbers with a fixed circle diameter ratio of K=0.67,and the optimum circle diameter ratio is K=0.67,after comparing the above-mentioned evaluation indexes for different circle diameters with a fixed balancing hole number of N=10.The optimal mechanical parameters are given for various combinations of five pipe sizes within DN50 to DN1000 and six equivalent diameter ratios.The optimal balancing hole number is 8 or 10,and the optimal center-circle diameter ratio K is between 0.64 and 0.73(in most cases,it is between 0.66 and 0.70).In the paper,the concept of momentum difference is proposed to evaluate the performance of a balanced orifice plate,and it is proved thatΔM reaching to the minimum value can be used as an auxiliary criterion for achieving an optimal mechanical parameter.The results of the study are of reference value for the mechanical design of a balanced orifice plate.