Research on Flow Correction Coefficient of Monophonic Ultrasonic Flowmeter

The key influential factors on flow correction coefficient of ultrasonic flowmeter were studied by using 3D CFD numerical simulation. Based on FLUENT, the natural gas pipeline flow fields were calculated numerically, with the inlet velocity ranged from 1m/s to 100m/s or the proportion of methane in natural gas ranged from 80% to 100%. The factors affecting the deviation of natural gas ultrasonic flowmeter and the variation trend of flow correction coefficient were analyzed, and compared with theoretical data. The results showed that the flow correction coefficient k decreased with the increasing of natural gas density at the same inlet velocity. Moreover, the flow correction coefficient increased with the increasing of inlet velocity when the natural gas density and others were fixed. And the variation trend was basically consistent with the theoretical value when the Reynolds number was more than 105. Due to the strong turbulence effect, the simulated value deviated from the theoretical value when the Reynolds number was less than 10
⁵
, so that a further correction was needed.