Dynamic characteristics of orifice flowmeter impulse response based on CFD simulation

Abstract

Because of its simple structure and ability to measure in reverse, orifice flowmeters are widely used in petroleum, chemical and other fields. In the measurement, the pipeline flow state instability occurs, which has a greater impact on the measurement performance of the orifice flowmeter. In order to study the influence of dynamic flow on the dynamic characteristics of orifice flowmeter. Based on CFD simulation, the dynamic characteristics of orifice flowmeter with different throttling ratio (β) under sinusoidal pulsating flow conditions is studied. Through the simulation of the internal flow field of the orifice flowmeter under the conditions of 7 different frequencies and 4 different amplitude combinations, the differential pressure values under different working conditions are extracted to analyze the amplitude-frequency characteristics and phase-frequency characteristics. The results show that the frequency has a great influence on the dynamic characteristics of the orifice flowmeter. At the throttling ratio is 0.2, the flow rate is 6 m 3 /h and the amplitude is 1.2m³/h, the orifice flowmeter amplitude-frequency characteristic linearity is as low as 1.9860%, phase difference is as low as -7.56°.