上游扰流对双锥流量计输出特性的影响

Study of the effects of upstream disturbed flow on the output characteristic of double-cone flowmeters

为研究双锥流量计的安装使用条件,利用Fluent仿真软件对50mm管径,直径比β分别为0.5、0.6、0.8的双锥流量计展开了上游半月型孔板扰流件作用下的数值模拟研究,并结合一定的实流实验加以验证模拟计算的正确性.通过速度场与压力场云图信息,定性地分析扰流件与直管段长度对双锥流量计流出系数的影响.最后,利用平均流出系数相对误差作为安装条件影响的主要评价标准,定量地给出了上游半月型孔板下各β所需的最短直管段长度.

To study the installation requirements and application conditions,a numerical simulation study on the double-cone flow meters with diameter rates of 0.5,0.6,0.8 and a pipe diameter of 50 mm was carried out with the upstream half-moon orifice,by using the Fluent,which was validated by an amount of experiment investigation.According to the distribution information of velocity and pressure field,the paper analyses the influence of the upstream disturbing device and the straight pipe length on the discharge coefficient of the double-cone meter qualitatively.By using the relative error of the averaged discharge coefficient as the main evaluating criterion,for three kinds of diameter rates,we obtained the shortest straight pipe length for the upstream half-moon orifice quantitatively.