Khamsin Virtual Racecar challenge 2013 (CFD model racing)

[astracrazy]

are we able to get stopwatch so we can input our own data from our own tests? i couldnt find it to download

Ric
did you download 0.8 first to get the add ons then patch to 1.0?

[RicME85]

I did yeah and then Im adding the extra bits in now for 1.0

[etsmc]

will cars built from the V1/V2 pack be accepted for the first race or once the pack with the fixed tub released?

[RicME85]

I have emailed Julien regarding Khamsin so thought I would share his response:

To run a test to check the configuration, it will be easier to just run a test. Use: https://dl.dropbox.com/u/40499338/Khams ... mplete.skp for example. Load the skp file in SketchUp, activate Khamsin tool and right-click -> Analysis -> go (local).

With the wind-tunnel:
- Open the skp file;
- Paste or import the car - with the provided wind-tunnel skp file, paste the car into the car-body group so that the imported car is part of the car-body group in the wind-tunnel skp file;
- If you are not able to paste the car into the car-body group (but do ensure it is imported as a group), you will need to do the following:

+ Khamsin tool -> right-click -> Define -> Volume
+ left button press (i.e press but do not release) on the group in which your car is imported, this should display a local menu;
+ move the mouse to the entry "Volume 0" - it should get highlighted in red, and release the left button;
+ Do the same and select "Close"
+ right-click -> Define -> Boundary Conditions
+ double left click on the the group in which your car is imported, this should display the boundary condition panel;
+ Change the name to "car" and the mesh size to "0.01"
+ Select "Close" by left button press over the group, etc.

- Then you can run the analysis: right-click -> Analysis -> go (local)

Anyone know how to use Paraview? I have run the test like Julien said at the start of his message but now it comes to reading results I have no idea. I have gone through the Khamsin menu (Results->Paraview) and it loads but I have no idea what to do from there.

[MisterX]

Hi all!

I made a request for registration to the competition, you know more or less how long it will take to be accepted?

thanks

[RicME85]

No exact time, it all depends on when Nick gets chance to do it, the competition is a side project in his life so doesnt get priority.

[CottrellGP]

Hi all not sure if this has been mentioned before but when i right click> and Analysis> go there is no local, just linux or amazon?

[RicME85]

You have set it up wrong, you need to turn off Linux server and AWS in the settings.

Ran a successful test on my 2012 car \o/
Started at 11:33am 6/3 and finished 00:44am 7/3.
For those interested, my dxdiag info:

Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.130104-1431)
Language: English (Regional Setting: English)
System Manufacturer: System manufacturer
System Model: P5K-E
BIOS: BIOS Date: 06/19/08 12:03:30 Ver: 08.00.12
Processor: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (4 CPUs), ~2.4GHz
Memory: 6144MB RAM
Available OS Memory: 6144MB RAM
Page File: 3584MB used, 8700MB available

[astracrazy]

took nearly 12 hours? aint to bad

[RicME85]

Another response from Julien:

Hi Richard,

Cool. I am very happy to know that you managed to get it running... It is always a great feeling when others are able to use what I am developing. If you have comments or feedback on the good and bad aspects, I am all for it.

1. swak4Foam: it would be required for the wheels - to account for the rotation of the wheels. If you do not include the wheels, you can just untick the box.

How to install it? I am using the blueCFD distribution, which includes swak4Foam. blueCFD-SingleCore is a free subset of blueCFD, which does not include swak4Foam. I am unsure how it can be added manually... You can purchase blueCFD from blueCAPE (check price with them, but believe it is around Euro70). I will drop them an email to see if they might be willing to add swak4Foam to their blueCFD-SingleCore for the KVRC.

There are a number of alternatives:
- build a port of openFoam and swak4Foam for windows on your own - probably time consuming and frustrating experience, not for the faint hearted;
- install openFoam and swak4Foam on a Linux computer on the same network as your windows box and use right-click->analysis->remote->linux - it is probably the easiest way, but require two computers on the same network;
- use Amazon EC2 (right-click->analysis->remote->Amazon EC2). If you want to do this, let me know as I need your amazon user id to allow access to the image. It is reasonably experimental, and Amazon EC2 will charge you per CPU hour (not expensive though).

2. Individual components: Just place it the same way as you did with the car. You probably want to get the correct height above the ground to correctly account for ground effects, otherwise the position in the domain should not matter much. Just be aware that a component that is optimised by itself may behave differently when included with the car. To optimise run time, you can look at a number of aspects: do you need to run for 1000 iterations? Can you coarsen the mesh resolution?

Thanks a lot for passing the information onto others. I am knee-deep into it and have difficulties with getting the right explanation.

Kind regards,
Julien

[julien.decharentenay]

Which links are broken???

For post-processing:
- Check the analysis output: right-click>Analysis>Output. Scroll down to the near the end and you should have the forces (in newton) and moment (in newton.meter to the 0,0,0 point). Both have two components: pressure induced forces/moment and viscous (molecular and turbulent) induced forces/moment.
- ParaView: right-click->Analysis>Paraview. In paraview:
+ Change time from 0 to the latest one (click on the up arrow);
+ Click on the apply button (on the left side of the screen);
+ Change the variable (may be called Solid Color) and may have to change the representation to "Surface" (it is a bit on the right of the variable in the toolbar) - on the left of the variable drop down, there are three buttons: rescale, edit scale and show legend (from right to left);
+ Just under the variable and representation in the toolbar, there are a few filters than can be applied: the section one is a good one.
+ Also, right-click (in the pipeline browser) on open and select the "xxxx.foam" file
+ In the object inspector: untick the internal mesh and tick the name containing car or car-body, then click apply. It should only show the car body. Check the pressure on the surface to see area of high and low pressure.

If all fails, have a check at the documentation...

Julien

[astracrazy]

hi guys

all looks quiet simple. Once Bt/Sky sort out my internet i can give it ago!

So we can't run rotation on the wheels in the free package at the moment, we would need to pay 70 euros for the add on to do it? was the gist of the e-mail. everything else we can do

[RicME85]

Julien - Iirc, EnSight and openFoam (blueCFD) are the links that have issues. I got my blueCFD from the 0.8 release and EnSight I have grabbed from the CEI website.

[RicME85]

Astra - Remember in a PM recently I mentioned a program for wing profiles? Well here it is, will be handy for everyone else, its called DesignFOIL

[astracrazy]

Astra - Remember in a PM recently I mentioned a program for wing profiles? Well here it is, will be handy for everyone else, its called DesignFOIL

nyc one mate. so you use that to create the co-ordinates then use is it cloud_v6 plug in to import them?