均速管流量传感器二维仿真方法

2D Numerical Method on Averaging Pitot Tubes

为了能够采用二维仿真方法准确预测均速管的差压及内部流场流动情况,根据3种原则得到均速管的5种二维简化模型,在11.18,m/s的流速下,采用这5种模型对DN,200菱形均速管分别以0.001 0和0.000,1两种残差进行仿真,发现截面4仿真所得的差压值与实验值之间的相对误差分别为0.91%和-1.9%,优于其他4种二维模型;采用截面4对DN,200菱形、Delta形均速管在其量程范围内,从量程下限开始,选择4个流量点在0.000,1残差下进行仿真,得到的最大相对误差分别为-3.30%和2.92%,经综合比较,可知相对于其他4种二维模型,截面4更适合于均速管流量计的内部流场仿真与仪表系数预测.

To accurately predict differential pressure and internal flow field of averaging Pitot tube by using 2D simu- lation method, five 2D simplified models, achieved through three principles, are studied. The five models are used respectively in the simulation of DN200 diamond averaging Pitot tube at the residuals of 0.001 and 0.000 1 and the speed of 11.18 m/s. After comparing the simulation data with the experimental data, it＇s found that the relative errors of cross-section 4 are 0.91% and -1.9%, respectively, which are better than the other four models. So the cross-section 4 is used to simulate the flow field of the DN200 diamond and Delta Pitot tube at four different velocity points within the flow range at the residual of 0.000 1. The results show that the maximum relative errors of diamond and Delta Pitot tubes are -3.3% and 2.92% respectively. Compared with the other four models, the model of section 4 is more suitable for flow field simulation and coefficient prediction of the averaging Pitot tube.