超声波流量计关于矩形流道的研究设计  

Research and design of ultrasonic flowmeter on rectangular flow channel

作　　者：金超[1] 杨鸣[1] Jin Chao;Yang Ming(School of Information Science and Engineering,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学信息科学与工程学院,浙江宁波315211

出　　处：《现代科学仪器》2019年第4期15-18,37,共5页Modern Scientific Instruments

摘　　要：针对时差法超声波流量计,在计算流速时需要对测得的线速度进行修正,修正系数在层流状态下随着雷诺数变化明显,容易引起较大的偏差。本文通过计算流体力学(CFD)数值仿真对管道内流速分布进行分析,计算面流速与线流速之比,说明了矩形流道可以通过加装整流片来减小修正系数随雷诺数的变化,提升超声波流量计在小流量计量时的准确度,并通过加长整流片解决了因流道间距过小而产生修正系数波动变化的问题,为研制非圆形测量管道的高精度超声波流量计提供设计方案。For the time difference method ultrasonic flowmeter,the measured linear velocity needs to be corrected when calculating the flow velocity.The correction coefficient changes significantly with the Reynolds number in the laminar flow state,which is likely to cause large deviation.In this paper,the numerical simulation of computational fluid dynamics(CFD)is used to analyze the flow velocity distribution in the pipeline,and the ratio of surface velocity to line velocity is calculated.It shows that the rectangular flow channel can reduce the variation of the correction coefficient with the Reynolds number by adding the rectifier,and improve the accuracy of the ultrasonic flowmeter in small flow measurement.Moreover,the problem of fluctuations in the correction coefficient caused by the too small flow path spacing is solved by lengthening the commutator piece,which provides a design scheme for developing a high-precision ultrasonic flowmeter for non-circular measuring pipes.

关 键 词：超声波流量计 矩形流道 修正系数 数值仿真 

分 类 号：TH814[机械工程—仪器科学与技术]