Numerical Simulation of Turbulent Natural Convection and Gas Radiation in Differentially Heated Cavities Using FVM, DOM and LES

摘要

Natural convection in differential heated cavities has been widely studied experimentally and numerically. However, experimental results usually differ from numerical solutions. Since in most of those experimental enclosures absolute temperatures of the walls are relatively high, it has been traced that these discrepancies could be due to surface or surface and gas radiation. Nevertheless, few studies have been done taking into account only surface radiation (non-participating medium) and much less taking into account surface and gas radiation (participating medium). When gases contained inside the cavity are participating in radiation the governing equations of motion of the fluid are coupled to the integro-differential equation of radiative transport (RTE) through a new term, the divergence of radiative heat transfer, affecting the fluid flow. The aim of the present work is to analyse the effect of surface radiation as well as both surface and gas radiation on the turbulent natural convection in a tall differentially heated cavity. Standard RANS methods and advanced LES formulations are used.