Modeling is mainly the basis of engineering and it is a suitable simplification of reality. The displaying expertise is to detect the fitting degree of disentanglement, recognize significant highlights from those that are insignificant in a specific application, and use designing judgment. This chapter presents a complete model specification of the solar chimney power plant on which all simulations and results are based and devoted to the presentation of the physical and numerical models by using in the CFD code ANSYS Fluent 17.0. The following will discuss the equations and models incorporated by ANSYS Fluent to model a solar chimney power plant. The governing equations will be presented, which describe the coupling of temperature fields, velocity, and pressure from the conservation equations. Then, the discretization methods and meshing used will be examined. Finally, the models for turbulence and radiation will be explored.