Physical properties change presumption manner inside the gas pipe, while physical properties change presumption programming, and the physical properties change

摘要

PROBLEM TO BE SOLVED: To provide a property change estimating method in a conduit used in a case where a gas transporting conduit is used in transporting a plurality of kinds of gases having different components, capable of easily determining a diffusing constant, time, and costs for estimating.;SOLUTION: The property change estimating method is provided for estimating the behavior of the property change of gas flowing in the gas conduit when the mixture ratio of different types of gases flowing in the gas conduit is changed. Based on the kinematic viscosity coefficient, gas flow rate, and the inner diameter of the conduit of each gas, it is determined in which of a laminar flow region, a turbulent flow region, or a transient region between the two regions the flow in the gas conduit belongs. The diffusion constant used for a diffusion equation is decided by using an equation prepared for the determined region out of predetermined equations different from each other prepared for each of the laminar flow region, the turbulent flow region, and the transient region.;COPYRIGHT: (C)2009,JPO&INPIT