CFD simulations of vapour cloud explosions using PDRFoam

Abstract

Computational Fluid Dynamics (CFD) has gained a lot of popularity in the consequence assessments of gas explosions in the past couple of decades. This work reviews Porosity/ Distributed Resistance (PDR) approach-based CFD solver (PDRFoam) for gas explosions. The PDR approach is used to model the effect of small-scale obstacles and only solve for the large scale congestion. PDR-based modified Favre averaged equations for mass, momentum, enthalpy, and regress variable are solved using PDRFoam solver, which is developed as a new application in OpenFOAM. The evaluation of the solver is done against medium-scale standard benchmark experiments. Further, the effect of block-age ratio, different types of fuels, and different obstacle diameters is explored. Using PDRFoam simulations, the pressure–time series, the flame arrival times, and the flame speeds are predicted and the same are compared with experiments. Compared to standard body-fitted grid simulations, the PDR approach is computationally economical; The predicted results are in good agreement with experiments.