Solar chimney converts solar thermal energy into kinetic energy to generate electricity and it is an alternative technology for electricity generation from solar energy. In this work, we are interested in the study of geometrical parameters on convection airflow within a solar chimney For this, we have considered a two-dimensional prototype model of a solar chimney The boundary conditions are chosen to be similar to those in reality. The considered mathematical model is a system of partial differential equations formed by the continuity, momentum, and energy equations in conjunction with the standard k-c turbulence model. The numerical simulations were performed by a commercial Computational Fluid Dynamics (CFD) code based on the finite volume method. Good agreements of the present results with experimental and numerical data were obtained. The effects of the tower and collector radius/ heights on the aerodynamic structure were studied and examined. The obtained results can be used for the design of new solar chimney systems.