Modelling Natural Turbulence of a Fluid in a 3-D Enclosure using Finite Difference Method and SIMPLE Method

  • J. K. Kimunguyi
  • B. N. Mutua
  • K. O. Awuor
Keywords: Turbulence, Natural Convention, Finite Difference Method, SIMPLE


The purpose of the study is to carry out a numerical investigation on turbulent natural convection fluid flow in a rectangular enclosure. A flow motion of the Newtonian fluid in the cavity was considered. To facilitate the analysis of the flow and thermal transfer rates, a set of non-dimensional equations governing the fluid flow was used. The time-averaging process of the mass, momentum and energy governing equations introduced nonlinear terms into the equations of mean flow namely Reynolds stress  and heat flux , which were modelled using the k-ɛ model. The RANS equations, energy and k-ɛ turbulent equations were first non-dimensionalized and the resulting equations discretized using Finite Difference Method and solved using SIMPLE. From the results, the velocity vectors go round in circles as they move towards the cold wall which is evident from the strong three-dimensional vortex generation mechanism that causes the hierarchy of eddies.