Parametric Analysis of Vortex Generators with Varrying Angle of Attack on a Passenger Car

PARAMETRIC         ANALYSIS         OF VORTEX         GENERATORS         WITH VARRYING ANGLE OF ATTACK ON A PASSENGER CAR

OBJECTIVE

The main objective of our project is to analyse the effect a vortex generator produces on a passenger car and can it be implemented on day to day basis on modern cars and what is the optimum orientation which produces the least drag which might help in increasing the fuel economy.

AHMED BODY ANALYSIS

Ahmed body geometry

[pic 1]

Parameters used for our simulation are:-

Velocity = 30m/s

Turbulence model = standard k epsilon model

Pressure based system and coupled solution method

Velocity contour  

[pic 2] 

The drag coefficient obtained on the analysis of Ahmed Body is 0.295 and the theoretical value of drag coefficient for 25-degree angle of depression is 0.29. This states that our turbulence model is valid

The cad model used for our simulation is

[pic 3] 

CFD analysis of our model which would act as a reference for our upcoming iterations Results

[pic 4] 

Drag coefficient = 0.42

Pressure contour

[pic 5] 

The forces acting on the car are  (-54.149225 -31.189578 -1040.2289)N

Velocity contour

[pic 6] 

Vortex generators oriented inline  

Cad with inline vortex generators

[pic 7] 

Results

[pic 8] 

The drag coefficient obtained with inline vortex generator is 0.447

Pressure contour

[pic 9] 

The forces acting on the car are (-40.322309 930.87165 -1104.1221)N

Velocity contour

[pic 10] 

Vortex generators oriented at 150  

Cad with 150 vortex generators

[pic 11] 

Results

[pic 12] 

The drag coefficient obtained  is 0.374

Pressure contour

[pic 13] 

The forces acting on the car are (26.688243 788.33121 -923.69134)

[pic 14] 

Vortex generators oriented at 300  

Cad with 300 vortex generators

[pic 15] 

 [pic 16] 

The drag coefficient obtained is 0.386

Pressure contour

[pic 17] 

The forces acting on the car are (-12.510799 674.43327 -956.80602)

[pic 18] 

Vortex generators oriented at 300 mirrored along centre

Cad with 300 mirrored along centre

[pic 19] 

[pic 20] 

The drag coefficient is 0.41

Pressure contour

[pic 21] 

The forces acting on the car are (6.8962819 852.64102 -1027.5175)N