标准孔板流量计内部流场的CFD数值模拟

通过在标准孔板流量计中引入CFD数值模拟,为流出系数的获取提供了新途径.对不可压缩流体在不同流量、不同直径比、不同孔板轴向厚度和不同流动介质下的内部流场进行了数值模拟计算,并将计算出的流出系数与根据ISO公式计算出的流出系数进行了分析对比.结果表明,随着结构参数和工作条件的改变,流出系数都会随之发生变化,但ISO公式对孔板厚度的变化不太敏感.CFD数值模拟可以作为标准孔板流量计的辅助设计与标定手段,以进一步提高孔板流量计计量的准确性.

CFD simulation of flow field in standard orifice plate flow meter

The utilization of CFD numerical simulation in standard orifice flow meter provides a new method on the estimation and optimization of discharge coefficient.This paper complemented numerical simulation onto the flow field of incompressible flow under different flow rate,diameter ratio,orifice thickness and flow media,by comparing and analyzing the discharge coefficient achieved from numerical simulation and the ISO empirical formula.It is indicated that,with the variation of structural parameters and working condition,the discharge coefficient will change correspondently,but ISO formula is not very sensitive to the thickness of orifice plate.The CFD numerical simulation can be adopted as a complementary design and certification tool in standard orifice flow meter,to enhance its measurement accuracy further more.