Radiation Effects on Turbulent Mixed Convection Channel Flow: Influence of WallEmissivity

The purpose of present study is to investigate theradiation effects on turbulent mixed convection flowbetween two vertical parallel plates kept at differenttemperatures. Two flow situations known as aiding andopposing flow are considered. Numerical simulations arecarried out by developing a solver in OpenFOAM. Thefour-equation low-Reynolds v۲  f turbulence model isemployed throughout the study. The working fluid isassumed to be gray, absorbing, emitting and scattering.The radiative transfer equation is solved using thediscrete ordinates method (DOM (S۸)). The effects ofwall emissivity on the flow and thermal fields and alsoNusselt number are addressed. Present results indicatethat with an increase in wall emissivity, influence ofradiation on the mean temperature profiles grows in bothaiding and opposing flow regions. This results in anincrease in bulk temperature and Nusselt number on bothaiding and opposing sides.

کلیدواژه ها:

Radiative heat transfer ، Turbulence ، Mixedconvection ، Vertical channel ، OpenFOAM