**1. Introduction**

Computational fluid dynamics (CFD) is a scientific tool capable of producing information about the main structures of a flowing fluid. As a knowledge area, it finds its origins in the discrete solution of the fundamental equations used in fluid dynamics, such as the mass conservation equation, the momentum conservation equations (based on Newton's second law), and the energy conservation equation (based on the first law of Thermodynamics). All the equations are solved in an approximate way using iterative algorithms to solve lineal algebraic equa‐ tions systems using matrices [1, 2].

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A CFD model has three sequential stages known as preprocessing, solving, and post-process‐ ing. In the first stage or preprocessing, the governing equations, properties, and boundary conditions are defined within a domain composed by small interconnected volumetric elements to model the fluid movement. During the second stage or solving process, the adequate selection of discretization schemes (temporal and spatial) for the governing equa‐ tions is carried out. Also, the convergence criteria or number of iterations, relaxation factors, and pressure and velocity coupling algorithm are set up at this stage. Finally, the postprocessing stage involves the analysis and interpretation of the obtained solutions using flow, temperature, and pressures fields [3].

Nowadays, there are different commercial codes developed in a friendly interface, such as ANSYS FLUENT, OPEN FOAM, CFX, X-FLOW, and COMSOL. All of them are capable of helping researchers and engineers at the three aforementioned CFD stages. Generally, the modules of these commercial softwares have been validated comparing the results obtained for specific information such as separation point, circulation length, drag and lift coefficients, and velocities, with experimental and/or analytical results. Very often, the experimental results used for comparison are obtained from carefully controlled experiments about topics such as flow around circular cylinders, flow over forward or backward facing step, flow over a venture, and jet flow, among others [4]. Respecting the programming languages commonly used to develop the CFD codes used in commercial software, the most frequently used are C++, FORTRAN, and lately MATLAB.
