超声流量计探头对流场及其测量性能影响研究  

Study on the influence of ultrasonic probes on flow field and measurement performance of ultrasonic flowmeter

作　　者：张朋勇[1] 郑丹丹[1] 徐天室[1] 张力新[2] 胡鹤鸣[3] 

机构地区：[1]天津大学电气与自动化工程学院,天津300072 [2]唐山汇中仪表有限公司,河北唐山063020 [3]中国计量科学研究院,北京100013

出　　处：《实验流体力学》2011年第3期60-65,共6页Journal of Experiments in Fluid Mechanics

基　　金：国家863计划资助项目(2008AA042207);天津大学自主创新基金

摘　　要：超声流量计探头安装位置会对其测量产生影响。对DN500超声流量计在探头全伸位置安装时的流场以及对超声流量计测量性能的影响进行了数值仿真研究。仿真结果表明,入口速度为0.3~8m/s时,由于探头伸入管道而造成超声流量计的测量误差为-1.25%^-1.9%,且随着入口速度增大,测量误差逐渐增大;当速度达到一定范围后,测量误差基本趋于稳定。在此基础上通过流场分析指出,由于探头附近区域存在回流,造成各声道线平均速度减小,导致测得的流量值偏小,因此测量误差为负。When the front surface of an ultrasonic probe is fully inserted into the interior of a channel, there will be an impact of the probe on the flow measurement. Numerical simulation was carried out to study the influence on the local flow field and measurement performance of multipath ultrasonic flowmeter with 0.5m diameter. Simulation results indicate that the probe can make -1.25%--1.9% measurement errors when the inlet velocity is 0.3-8m/s. In addition, the measurement error increases with the inlet velocity increasing. And the measurement error is going to be stable, when the inlet velocity reaches a certain range. From the analysis of the flow field, there exist reversed flows in the vicinity of ultrasonic probes, which reduce the mean flow velocity of each path and flow rate measured. So the measurement error is negative.

关 键 词：多声道超声流量计 数值仿真 超声探头 测量误差 流场影响 

分 类 号：TP212.9[自动化与计算机技术—检测技术与自动化装置]