弯管对超声波流量计测量精度的影响及改善措施

流体经过弯管易产生二次流、涡流等扰流情况,使流道内流速分布不均匀,会对流量计的测量精度产生影响.为研究扰流对流量计的影响,利用建模与模拟仿真方式,对G16型号单流道流量计在入口管道为双弯管及半月双弯管情况下的计量效果展开研究,计算两种情况下相对于入口管道为直管时的流量误差度,以此表明单流道流量计在安装弯管时,扰流给测量...

Effect of elbow on measurement accuracy of ultrasonic flowmeter and the improvement measures

When the fluid passes through the elbow of a channel, it is easy to produce secondary flow, eddy current and other complications, resulting in uneven velocity distribution in the channel. These complexities will affect the measurement accuracy of the flowmeter. In order to study the effect of turbulence on flowmeter, the measurement effect of G16 single channel flowmeter is investigated when the inlet pipe bears either double elbow or half moon double elbow by modeling and simulation. The flow error is calculated when the inlet pipe is straight pipe, so as to show the error was caused by the turbulence to the measurement result when the single channel flowmeter is installed with elbow. In order to reduce this kind of error, the model of G16 double channel flowmeter is established, and the simulation experiment is conducted under the same conditions. Finally, the obtained data are compared with the corresponding data of single channel flowmeter. The results show that the measurement accuracy of double channel flowmeter is higher than that of single channel flowmeter at each flow point. When the flow points are 2.5m3·h-1 and 10m3·h-1 and the inlet pipe is half moon double elbow, the measurement accuracy is improved by 1.0940% and 1.2058% respectively. When the inlet pipe is double elbow, the measurement accuracy is improved by 2.1120% and 2.2930% respectively. Compared with the single channel flowmeter, the double channel flowmeter greatly inhibits the disturbance caused by the elbow, and the measurement accuracy is thus significantly improved.