ES174 Car Aerodynamics

To learn design philosophy and design procedures by using CFD package;
To provide an introduction to computational fluid dynamics for car aerodynamics through an open-ended design project

To know basic concepts of fluid dynamics and car aerodynamics;
To use a commercial CFD software (COSMOSFlowWorks) to solve engineering fluid problems;
To appreciate the potentials and limitations of CFD as part of the design process;
To perform basic analysis of the CFD results and optimasation.

Prepare two 3-D car prototype-models and a wind tunnel model using Solidworks;
- Model A: build a car model of your own choice.
- Model B: A box-shaped car with the same dimensions (length, width and height),
- Build a wind tunnel with lids on both end.
Assemble the car with the wind tunnel;
- Avoid point contact between the car wheels and the tunnel floor.
Create a project using CosmosFlowWork;
- Set the inlet velocities.
- Refer to ‘Tutorial on CFD Analysis of Air Flow Around Car Using Solidworks/COSMOSFloWorks’.
Run simulations for the flow field around the car;
- Find the drag force
- Calculate drag coefficients
- Plot the these values against velocity (converted to miles per hour)
Analyse the results (aerodynamic performances of your car) and make improvement to the design of your car body;
Compare two simulation results to find the effect of the car design on aerodynamics;
Run further simulations, if necessary, to improve aerodynamics;
Write up your report.

You will hand in an individual report by the end of Week 22 (2pm, Friday 29 February 2008);
The total length of the report is 4 pages of A4 paper.
How to write a report!
You need to run three simulations for this exercise.
- Test simulation with either Model A or Model B with a lower resolution (Program running time should be no longer than 30 minutes).
- Main simulation with Model A (Program running time can take up to 3 hours).
- Main simulation with Model B with almost identical conditions.
The report must include evidence of your achievements together with analysis and discussion based on fluid dynamic knowledge;
NO accompanying CD is required.

Credit: 4 CATS - The average students input time is 40 hours.