The paper presented for simulating the complete physics of the second-order Stokes wave equation using CFD code ANSYS-FLUENT software and volume of fluid (VOF) method in a 2-D numerical wave tank (NWT). The main objective of this work is to study the effect of wave steepness on ocean waves in the intermediate depth of water at low Ursell numbers (U_r<18). The inlet velocity method generates the secondorder water wave in the numerical model for achieving this objective. Generally, three methods are used to generate the wave in a numerical wave tank: (1) inlet velocity method; (2) flap-type method; and (3) piston type method. I have used the inlet velocity method to generate the second-order water wave in the simulation. In this study, the simulation results of the model are compared with the analytical results. It shows that the accuracy ofthe numerical results is in good agreement with the analytical results. The MATLAB code solves the secondorder Stokes wave equation. Six tests under different wave heights have been conducted at two regions in an NWT to analyze the wave theory. It also shows that high energy flow is concentrated near the free surface. It also shows that the nonlinearity effect increases with the increase of wave steepness and found horizontal and vertical velocity increases with wave steepness. This water wave study improves the coastal engineeringapplication for further investigation and extracts wave energy from the ocean.