By the flow factor fluid yes deformation capacity control manner and its device

摘要

PROBLEM TO BE SOLVED: To obtain the method for performing high-precision flow rate control over different kinds of gas by one flow rate controller by calculating a factor under specific conditions and calculating the flow rate of another gas kind when the gas kind is circulated through the same orifice under conditions of the same upstream pressure and the same upstream temperature on condition that the calculated flow rate of one gas kind is specific. ;SOLUTION: Flow factors FF is calculated by gas kinds from FF=(k/γs)(2/(κ+1))1/(κ-1)(κ/((κ+1)R))1/2 and on condition that the calculated flow rate of a gas kind A is QA, the flow rate QB of a gas kind B is calculated from QB=(FFB/FFA)QA when the gas kind B is circulated through the same orifice under the conditions of the same upstream side pressure and the same upstream temperature. Here, γs is the density of gas in a standard state, κ is the specific heat ratio of the gas, R is the gas constant, (k) is a proportion constant which does not depend upon the gas kind, FFA is the flow factor of the gas kind A, and FFB is the flow factor of the gas kind B.;COPYRIGHT: (C)2000,JPO