Turbulent Natural Convection in an Enclosure Using Two Equation k-ω Turbulence Model and Piso Method

Abstract

The natural convection on a surface depends on the geometry as well as its orientation. In natural convection, the motion of the fluid takes place by natural means such as gravitational force and buoyancy. Turbulent natural convection in an enclosure has been studied in the past but so far the prediction of heat transfer within an enclosure has not been completely established. The aim of this study is to predict the transfer of heat as a result of natural convection inside a square cavity filled with air using k-omega. Natural turbulent convection in square air cavities having isothermal vertical wall and highly-heat conductivity horizontal wall was carried out. The distribution of the temperature and velocity in the enclosure was determined for various Rayleigh numbers .The process involved numerically simulating the flow of the fluid inside an enclosure using the k-omega turbulence model and since pressure gradient was considered in the momentum equation the PISO Method was used. It was found out that in an enclosure environment, the natural turbulence flow is responsible for temperature distribution. Temperature profiles are important for thermal comfort (including air velocity, temperature and humidity levels), efficiency of energy balance and the effectiveness of the ventilation system when modeling air flow in buildings.