【摘要】 在ISO5167-1和GB/T2624-93这两份标准文件中,都列入了确定差压式流量计参数的内容,实质上这是一个超越方程的数值求解问题。这两份文件均选择了割线法求解,这是正确的;但在如何正确地应用割线法求解计算流量的基本方程中,此二标准都存在一些问题,影响到所求参数时的正确性及有效性。为此,本文探讨了割线法的实质、有关其收敛性的分析及其在确定差压式流量计参数时的正确应用,这对于正确地推广运用这两个标准文件有着重要的意义。更多还原

【Abstract】 In the international standard ISO 5167-1 and the Chinese standard GB/T 2624-93 ,there are some contents concerning about how to determine the parameters of differential pressure flowmeter,the secant method was adopted for solving this problem in both standards ,but the concrete way to apply the secant method in these standards is in confuxion. Therefore ,the essence ,the convergency,the necessary and the sufficient conditions of secant method are discussed in detial ,then the best and the most correct way for using the secant method to determine the parameters in flowrate equation of differential pressure flowmeter is presented. Comparing the numerical results from this work and GB/T 2624-93,it is shown that the suggested approach is the most efficient one and is very important for design and application of differential pressure flowmeter.更多还原