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 Maxime31850 April 27, 2013 07:19

LSR (Land Speed Record) car simulation

Hi,

I'm a student who is doing analysis concerning a wheel driven Land Speed Record car. I've received the datas concerning the maximum speed that the car can reach, which is 460 mph.

I am using the software ANSYS v14.0 to draw, mesh the geometry and an old version of FLUENT to run my 3D simulations.

Therefore, I've encountered some problems concerning the FLUENT simulation.

As I said on the top of this post, the maximum speed of the car will be 460mph, which means that the type of flow is compressible ( Mach Number = 0,6 >0,3).

As a consequence, I cannot use the same boundary entities like for a incompressible flow. I used then Pressure Far Field for the right and left side (as pressure far field inlet and pressure far field outlet) and on the top (pressure far field top).

The problem is that when I tried to run the simulation on FLUENT, the residuals never converged or when I change some parameters some errors appeared.

Here are the parameters I've set in FLUENT for my last simulation :

Define : Models : energy equation : Ok
viscous model : k-epsilon model (standard)
Materials : air : ideal gas from the density
Operating conditions : 0 for the gauge pressure
Boundary conditions : gauge pressure : 101325 Pa
mach number : 0,6
x component flow direction : -1
Turbulence : turbulent viscosity ratio
5% and 5 for the ratio

After that in the tab Solve : I initialize from Pressure far field inlet and run the simulation.

I think the residuals don't converged because of the parameters but I don't really exactly know what do I have to put.
Could you give me some advices concerning them ?

Thank you very much

 Far April 27, 2013 11:15

Are you going to pay for the advice or consultancy ?

 Maxime31850 April 27, 2013 12:57

Hey Far,
it is a student work, I didn't think about spending money for it. Free advice are not possible??

Cheers

 Far April 27, 2013 14:06