Khamsin Virtual Racecar Challenge 2015

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2015

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I think you are probably better places to advise on the number of cells. My take is that it is around 1 to 1.5 millions cells, but I haven't really spend a lot of time testing it...

julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2015

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By the way I forgot to mention that I tried to load an openfoam result using ParaView from the OCCFD v1.0. The raw size of the results is getting too much for my computer. I will probably have to find some workaround such as converting the results to VTK format prior to loading them into ParaView and select only specific variables. Let me know how you guys are going with it.

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RicME85
52
Joined: 09 Feb 2012, 13:11
Location: Derby

Re: Khamsin Virtual Racecar Challenge 2015

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You not still using that Pentium 4 are you?

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machin
162
Joined: 25 Nov 2008, 14:45

Re: Khamsin Virtual Racecar Challenge 2015

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cdsavage wrote: COG will definitely be within a percent or two of 45 front / 55 rear. We're just waiting on confirmation from Richard (virtual stopwatch).
I can confirm 45:55 front to rear weight distribution, So you should be aiming for the same aero balance. I'll get some aero vs lap time charts sorted out over the weekend.
COMPETITION CAR ENGINEERING -Home of VIRTUAL STOPWATCH

julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2015

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RicME85 wrote:You not still using that Pentium 4 are you?
It wasn't worth it trying to get it from Oz to UK - so it has made a one-way trip to the recycling. I upgraded to a Core-2 Duo @ 2.4GHz - probably just made it into the late 2000s technology...

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CAEdevice
49
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2015

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RicME85 wrote:You not still using that Pentium 4 are you?
Maybe you will not believe it, but I have a Pentium4 still working in my office :)

Xwang
Xwang
29
Joined: 02 Dec 2012, 11:12

Re: Khamsin Virtual Racecar Challenge 2015

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Is an intel i7 laptop with 16gb ram enough for this cfd calculations?

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RicME85
52
Joined: 09 Feb 2012, 13:11
Location: Derby

Re: Khamsin Virtual Racecar Challenge 2015

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yeah, will take time but it will definitely work

MadMatt
MadMatt
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Joined: 08 Jan 2011, 16:04

Re: Khamsin Virtual Racecar Challenge 2015

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RicME85 wrote:yeah, will take time but it will definitely work
Take time? On what do you base your conclusion?

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CAEdevice
49
Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2015

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16gb ram and i7 are a very good hardware for kvrc cfd simulations (less then 20x10^6 cells).

MadMatt
MadMatt
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Joined: 08 Jan 2011, 16:04

Re: Khamsin Virtual Racecar Challenge 2015

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CAEdevice wrote:16gb ram and i7 are a very good hardware for kvrc cfd simulations (less then 20x10^6 cells).
Agree. The only thing I would advice is to pay attention to heat. Having your CPU flat out for a certain duration can cause it to overheat quite badly, and eventually shut down (or worse), so while you are running your simulation, just make sure you lift (at least the back of) your laptop to allow air to enter the fan underneath your machine.

Usually putting a book lifting the rear of the laptop is enough.

MadMatt
MadMatt
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Joined: 08 Jan 2011, 16:04

Re: Khamsin Virtual Racecar Challenge 2015

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How long does it take to complete a simulation for those who have performed one using OCCFD 1.0?

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CAEdevice
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Joined: 09 Jan 2014, 15:33
Location: Erba, Italy

Re: Khamsin Virtual Racecar Challenge 2015

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MadMatt wrote:How long does it take to complete a simulation for those who have performed one using OCCFD 1.0?
With the last release (1.0) I don't know exactly, I estimate less than 3h

julien.decharentenay
julien.decharentenay
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Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2015

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Gents, there is a drastic increase in computational time with v1.0 compared to the earlier version. It is all to do with the mesh size... The light version should be a lot faster...

It is not easy to find the "right" compromise between mesh size and computational time #-o

julien.decharentenay
julien.decharentenay
10
Joined: 02 Jun 2012, 12:31

Re: Khamsin Virtual Racecar Challenge 2015

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I have put out a very minor upgrade - increase the mesh limit following a query from CAEdevice. No other changes...

http://www.khamsinvirtualracecarchallen ... .0-001.zip