Case Study of Accidental Chlorine Release in the Urban Area Using CFD and Acceleration of the Simulation

Computational Fluid Dynamics is widely used to simulate accidental hazardous chemical releases. In the urban area where dispersion obstacles are large and abundant, CFD would be the best choice to simulate the toxic chemical dispersion. In this paper, one industrial complex which is adjacent to residential area was chosen for the simulation and tested for 10 cases of the wind condition. One worst case was selected and solved for 1-hour after the chlorine release begins. And then for the vulnerable points in the simulation volume, toxic load and probability of death was calculated. After that, using Courant-Friedrich-Levy number, time stepping scheme of the implicit Euler method was modified to increase timte-linearly to make simulation faster but to keep robustness. With combination of linear CFL number and parallel solvers, CPU time of the CFD simulation became one-forth of the base case.