A numerical investigation on free convection in a porous wavy chamber with non-uniform side wall will be conducted, with findings for various Rayleigh numbers and various porosity of the medium. Here, Rayleigh number changes from 103≤ Ra ≤ 106 and porosity of the medium used can be changed through Darcy number10-4≤ Da ≤ 10-2. Streamlineand isotherm plotswill be monitored for changes. In this project, an enclosed square porous chamber with thermally insulated walls and unusual side wall is studied.heat transfer rate is calculated for three different cases: case 1 is a flat wall, case 2 is a sinusoidal side wall and Case 3 is a zig zag side wall, the rate of heat transfer is calculated based on the number of undulation (d=0,1,2,3) of the side wall. All of the cases will be compared to see which has the best heat transfer rate.