The aim of this work is to perform experimental investigations on the temperature of the surface velocity of air, heat transfer and the flow characteristics for natural convection through parabolic profile of fixed dimensions having a circular orifice of constant diameter; heat supplied, and to propose suitable correlations for the same. Establishing an experimental relationship between the dimensionless quantities in the case of buoyancy induced flow through a circular orifice in which the heat energy is incident on the surface is the main activity involved. The main parameters of interest in this study such as the values of heat flux, heat transfer coefficient and buoyancy induced flow are also made used to achieve the objectives. The work also exhibits the design and fabrication of the experimental setup and collection of experimental data. Then the graphical analysis of the results is obtained. The ultimate result is in the form of a relationship between the Reynolds number versus Grashof number for different heat fluxes. The relationship between Reynolds and Grashof number has been established and it matches with the theoretical one in the limits of experimental errors. The relationship between these two numbers is a fifth degree polynomial. The relation is independent of the dimensions of the test section and thus any test section can be analyzed given, the dimensions. Thus performance characteristics of a plant can be predicted by making a small model of the whole system which is geometrically similar and then comparisons can be drawn.