提高差压式流量计的测量准确度

Research on improving measurement accuracy of differential pressure flowmeter

根据差压式流量计计算公式,从理论上分析了可量化的影响量因素,从设计、补偿、安装和变送器应用四个方面阐述了提高设计数据准确性、提高流出系数精度、采用密度补偿、采用气体膨胀系数补偿、采用压缩系数补偿、采用全补偿的测量模型,优化安装位置、满足直管段要求、保证安装同心度和优化取压口位置、提高差压测量准确度及信号传递准确度、变送器配置等可提高差压式流量计实际使用准确度的方法,使差压式流量计能够适应当前工业生产的需求,直接面对高准确度大量程比的挑战。

The article theoretically analyzes the quantifiable influence factors.Based on the four aspects of design,compensation,installation and transmitter application,this article describes the methods to improve the accuracy of the differential pressure flowmeter,such as improving the accuracy of design data,discharge coefficient,D/P measurement and signal transmission,using density compensation,gas expansion coefficient compensation and compression coefficient compensation,adopting fully compensated mathematical model,optimized installation position,guaranteed installation concentricity&optimized pressure tapping port position,optimized transmitter configuration and straight pipe lengths that can meet the measuring requirements,etc.The purpose of this article is to enable the differential pressure flow meter to meet the needs of modern industrial production and win the challenge of high accuracy and large turndown ratio measurement.