Abstract: The present work represents a parametric study with experimental and numerical work to study the natural convection heat transfer from a cube which represent an electric module fixed in a relatively long duct tilted at different angles of (horizontal), , and . Module side length (L=30mm) fixed at different locations of (X/L=5,10 and 15) with different input power of (0.147, 0.51, 0.96, 1.65, 2.34 and 3.075) Watt, which represent a heat flux of (32.67, 113.33, 213.33, 366.67, 520 and 683.33) W/m2 respectively.