Problem 3 Write a short proposal a page or two explaining ho

Problem 3: Write a short proposal (a page or two) explaining how you will find the flow over a

simplified car model, under normal driving conditions, using FLUENT. Identify the main

steps, the critical issues, and the expected outcome.

Solution

The flow over a simplified car model under normal driving conditions is highly turbulent. While designing a new road vehicle the structure of flow should be kept in mind. The flow is characterized by large-scale separation and recirculation regions, a complex wake flow, long trailing vortices and interaction of boundary layer flow on vehicle and ground. ANSYS Fluent software contains the broad physical modeling capabilities needed to model flow, turbulence, heat transfer, and reactions for industrial applications.

Firstly, the computational model is imported using geometry feature in the desired unit from file menu in ANSYS. Then click on import under Tree Outline and select generate. Then develop the enclosure using dropdown tool menu. then generate the mesh using Mesh option under project tree. Once the mesh is generated click on wireframe under top menu bar. Then create name selection over the enclosure, like the front face as inlet while the rear face as outlet. Then click on settings and select double precision. After that select material as fluid (air).

Then define boundary conditions for inlet and outlet faces defined previously. Boundary condition for inlet is velocity of 350m/s. Under solution, Turn soultion initialization as standard initialization and compute from as inlet, then select initialise option at the bottom and click run calculation under solution. Select number of iteration as 35 and click on calculate. It will start the calculating the solution. Once it is run go to Ansys and see the results.

After successful simulation get net forces at different position and dimension. You can compare the forces at different dimension and position and find out the optimum condition at which coefficient of drag is minimum.