STUDY ON IMPROVING NUMERICAL STABILITY BY APPLYING FILTER OPERATION TO CONCENTRATION FLUX FOR REVERSE SIMULATION TO IDENTIFY POLLUTANT SOURCE

Abstract

A Reverse simulation, which is the solution of the transport equation in negative time, is a method for identifying pollutant source with CFD. However, there is a numerical instability problem with solving the diffusion term. We proposed a method for improving numerical instability⁸⁾. This method applies a lo-pass filter to concentration field. This improves numerical instability, but analysis results of concentration field spread diffusely.
Hereinbefore, we propose a method to apply a low-pass filter to concentration flux in order to prevent concentration field from spreading diffusely and identify pollutant source with reverse simulation. As the result, the proposed method is useful to improve the precision of reverse simulation.