气体超声波流量计改善流场适应性的研究

Research on Improving Flow Field Adaptability of Gas Ultrasonic Flowmeter

流场形态的变化显著影响气体超声波流量计的测量性能,安装在流量计前方的弯头、阀门等设备可能会改变超声波流量计测量段的流场形态,从而造成较大的测量误差。为减小流场形态改变带来的影响,本文以DN40气体超声波流量计为研究对象,在流量计的测量段采用矩形结构,用数值模拟和实验验证相结合的方式,研究了流量计前方存在90°弯头时对不同尺寸矩形结构测量性能的影响。研究结果表明,随着矩形结构的长宽比的减小,弯头的影响会显著减小。本研究给出了具体的优化方案,研究成果可为小管径超声波气体流量计的设计和结构优化提供参考。

The change of flow field shape significantly affects the measurement performance of gas ultrasonic flowmeter. The elbow,valve and other equipment installed in the front of the flowmeter can change the flow field shape in the measurement section of the ultrasonic flowmeter and cause large measurement error. In order to reduce the influence of flow field changing,the rectangle structure are used in measurement section of a DN40 gas ultrasonic flowmeter,the influence of 90° elbow located in the front of flowmeter on measurement performance are studied by combing numerical simulation and experiments while different size rectangular structure are used in measurement section. The results show that with the reduction of the aspect ratio of the rectangular structure,the influence of the elbow decrease significantly. The experimental results verify the correctness of the numerical simulation,and the research results of this paper can provide reference for the design and structure optimization of small-diameter ultrasonic gas flowmeter.