Khamsin Virtual Racecar challenge 2013 (CFD model racing)

Post here information about your own engineering projects, including but not limited to building your own car or designing a virtual car through CAD.
astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Ye the cross section idea could work

What about:

On a transverse line ##mm forward of the rear wheel centre line, located between ##mm and ##mm from the car centre line and ##mm and ##mm above the reference plane there must be a minimum projected area of ##mm2
Last edited by astracrazy on 19 Nov 2013, 14:10, edited 1 time in total.

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Announcement - KVRC 2014

When Nick left, I spoke to Julien about helping him with the running of KVRC and offered to help him for 2014 by taking up some of the jobs Nick was doing for 2013 - to which he agreed. I want to make sure everybody knows I am not here to try take over the competition, in fact we have both agreed to make sure we stay as open with everybody as possible whilst putting KVRC together for 2014. So far many of you have had your say on changes and suggestions and that must continue.

My main role at the moment is to bring everything together. We are getting some great ideas and some great help as well (cdsavage for example has been fantastic with his work on the rules). What I'm going to be doing is taking all this and creating that final package and putting it all in place. Going forward through the competition I will be checking the cars are legal and helping to provide the results.

My aim is to try and have everything in place and set towards the end of December (mostly in terms of the rules) so everyone gets about 3 months to work on there cars with fixed rules in place

We have put together a rule book which is mostly based on what cdsavage produced, I've just rearranged it to help those who maybe aren't that clued up on the regs. There will be a few changes to try and keep it relevant and checkable on submission. A goal of mine is to make sure that if its in the rules its checked, that way everybody knows where they stand.

It is just the first draft though, so when it is released in the next few days please have a read and see what you think. As I said above, our aim is to be as open as possible, so please suggest anything which you perhaps think should be added, changed or removed. Again full credit to cdsavage for his work on giving us a great platform to work from.

Julien has already announced another change we are making where you will have the opportunity to re-submit your car if it is deemed illegal. Adding a time penalty is a good solution but its not always a fair one. This way you will be given a few days to rectify your car to make it legal - then resubmit. To avoid the illegal cars getting an extra few days to make performance upgrades, 360deg photo's will be taken of the car to ensure the only changes on re-submission are illegal parts.

Things to tie up:
- Engines. Do we want a spec engine? Or, should we define the position and minimum area so people are free to put a box there if they wish (its enclosed in bodywork so i guess it doesn't matter what it looks like), use there own or use last years?
- Sidepods. I think we should go with the minimum area at a cross section?
- Rule Book. Released in the next few days will need feedback from you guys
- Suspension. If somebody wants to make a new version of this please let me know

We have:
Sketchup rule boxes which will also tie in with the rule book
Gearbox and rear crash structure
Wheels/Brake Ducts

Many thanks guys for all your help so far and in the future.

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

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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I just wanted to confirm astracrazy's involvement in the challenge as per his post. My thanks to him for stepping up and taking on the role and responsibilities.

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Draft Files

Hi Guys,

Here is a first draft of the KVRC rule book. As i said, a lot is from cdsavage so some credit needs to go his way. Please have a read and let me have some feedback so we can continue to move forward.

http://www.mediafire.com/view/25k36r2d7 ... draft1.pdf

Below is the rule boxes. Again, cdsavage did try to provide us this but unfortunately as it was a .stl file there wasn't the flexibility within sketchup Again, if i can ask you guys who have time to check everything is where its meant to me. There will be more added to this file (such as rule boxes in relation to the rule book) before the 'pack' is created and finalised.

http://www.mediafire.com/download/3s1r3 ... ulebox.skp

Thanks for your help and feedback

cdsavage
cdsavage
19
Joined: 25 Apr 2010, 13:28

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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The stl files should import fine as long as you have that plugin - you just need to give it a while to import, its quite slow. If it won't work for some reason then I'll send you the skp file with the stl files already imported.

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Yes please do that mate. When i was trying i kept getting errors. Cheerz

cdsavage
cdsavage
19
Joined: 25 Apr 2010, 13:28

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Good work. I have a lot of comments/changes, but dont take that the wrong way - just want to make sure we have a good rules package to work from :)

K1 - I would suggest just defining y=0 as being the FWCL, y=3400 as the RWCL, and z=0 as the reference plane. This matches up with the regulation boxes I have built.

K3.5 - Why the 450 and 300 dimension limits? I dont think they are necessary.

K4.3 - The 10mm thickness rule makes sense but I dont understand the other changes here:
-I see you took the 40000mm^2 dimension from the F1 regs, but this is for the whole headrest, not just the portion sitting on top of the cockpit template as we are using. As a result 40000mm^2 would be huge. I had it at 6000, which results in a fairly normal sized headrest.
-"forwardmost point on a transverse line" is confusing if it is just a planar face parallel to and at a distance from plane CC.
-Why the 230 and 725 dimensions? Stating the distance from CC and "must lie entirely above the top face of the template, with the bottom edge lying on the top face of the template" should define it enough.

Have a look at the image in my V2 draft (cockpit template and headrest) to see what I originally intended for the headrest area. Keep in mind that the template below it is enclosed in bodywork.

K4.4 - This rule is redundant since we are requiring that the cockpit template must be enclosed in bodywork

Last sentence of K5.1 - I have no problem keeping the center of area rule but I imagine it is difficult to measure in sketchup.

K5.3 - I would specify that it applies only to the front wing and then get rid of the 450mm dimension (just for simplicity)

-Unless I missed it somewhere, I think you got rid of 3.7.8. I think this needs to be in there because it has an impact on the shape of the nose and FW pillars. Maybe there is a more simple way of communicating the intent of this rule.

K5.5 - I know I included it in my draft but this might be difficult to measure in sketchup.

-I think you removed the language governing the FW pylons, which is probably a good idea since I have made a box for this area, you can just add a simplified rule stating that this box can only contain the FW pylons (maybe with a limitation on their individual width). You may want to change the rule on rear wing pylons to match (there is a box for that as well).

K6.1 - I will make a box so you dont have to include the dimensions at the start. Also maybe the last part should be reworded to just state "the minimum distance between the two elements must be between 10mm and 20mm" (increase the maximum a bit to allow for potential problems with meshing). You also removed the rule stating that the chord of the lower element must be greater than the chord of the upper element, which I would keep.

K6.4 - I have a box for the volume for the exhaust exit, so B, C and D are not necessary. Also I think the exclusion area behind the exhaust is missing, but it may not be too important given that exhaust effects are not simulated.

K7.1 - You removed the language from 3.12.1 (all bodywork situated....and visible from underneath must form surfaces which lie on one of two parallel planes, the reference plane or the step plane, the step plane being 50mm above the reference plane), which I would keep - that way it is unambiguous and in line with the F1 regs.

-You removed 3.12.4 which I would keep, at least in some form (just stating that the boundaries of the reference plane and step planes may be curved up/down with radii of max 25mm, and the boundary of the step plane may be curved up with a max radius of 50mm) - without this you are overly restricted in the shape of leading edge or sides of the floor

K8.1 - I have a template shape included in the reg boxes, you could refer to this instead of listing the dimensions. Also I think you removed 3.16.1b (I also have a template for this) which I think you should keep, otherwise it is possible to have an unrealistically slim engine cover.

K8.2 - The "located between" isnt needed. There is a separate volume for just this rule. Also you removed the language forbidding holes, which I think you should keep in some form - otherwise it is possible to have cooling outlets anywhere on the car.

K8.3 - What is this rule for? I think it is all already covered by 8.2.

K9 - You removed the rule on the orientation of the mirror, without which you could have a mirror pointing sideways with a much lower frontal area. It might be worth considering just ignoring mirrors entirely and not requiring that cars have them. If we are keeping them then I will make a box so that K9.3 can be removed.

One last thing - the original areas I used for inlets and outlets werent really based on anything in particular, I dont know whether the current values need changing.

I will update the reg boxes and PM you a .skp file when I'm done.

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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No offence taken, i want this sort of feedback :). its easy to go around in circles with this
K1
I'll add this to my list of proposed changes, as the way you have defined it, its much better. The only reason the actual positioning is different (to yours) is i kept it the same as last year. In terms of picking it up and placing it inside the cfd tunnel. Its something i'll take to Julien regarding perhaps moving it. I doubt its a problem.
K3.5 - Why the 450 and 300 dimension limits? I dont think they are necessary.
I kinda agree. The only reason i put it in is because last year the challenge was loosely on the f1 regs, this year we have our own rule book so where the sidepods must essentially start isn't defined (f1 regs define it because of the side impact structure i believe?).
K4.3
- I agree 40000 may be to big, but I think 6000 might be to small. Let me look into it more against my 2013 model
- Will be changed to: "Parallel to and at a distance 100mm forward of section CC" ?
- Whilst it is defined it must lay essentially on top of the tub, I put those restriction in purely to prevent possible exploits. There would be nothing stopping people doing a very tall and thin face for example.
K4.4
We need something to force the creation of the side head rests. Maybe I've got myself confused?
K5.3 - I would specify that it applies only to the front wing and then get rid of the 450mm dimension (just for simplicity)
- I think you got rid of 3.7.8.
- I've put in brackets it's relevant to the front wing to help. The 425mm essentially defines it to just the front wing, without it the rule we refer to everything 685mm from the car centre line
- Your right i've missed that, I will add that in now as it is stated in 3.7.8. Obviously if someone thinks of a better way of writing it we'll change it:

"Only a single section, which must be open, may be contained within any longitudinal vertical
cross section taken parallel to the car centre line forward of a point 150mm ahead of the front
wheel centre line, less than 250mm from the car centre line and more than 125mm above the
reference plane."
K5.5
- Your right so will add it to my proposed changes list to remove.
- I'll look at your file, and write up a proposed rule regarding the FW pylons
K6.1
- Looking back 6.1 is governed by the main volume anyway so can be removed
- Good idea regarding 10-20mm (added to list)
- Good spot regarding chord (added to list)
K6.4
- I think we should just keep b,c,d just to avoid confusion, but still have the box to tie it up
- Yes, i removed the bodywork exclusion zone because its not tested so was a redundant rule
K7.1
- Added to list
K8.1
- I think we should keep the dimensions purely to avoid confusion, that way it can tie in with your file
- 3.16.1b added to list
K8.2/K8.3
- K8.3 should be K8.2. I wanted to make it as simple as possible instead of spreading the rule across 4 different areas like in the f1 rules. But your right the language regarding wholes needs to be added. Thoughts?
- I saved K8.3 for the minimum area at a cross section rule which we still hadn't come up with. Got confused :)
K9
- Orientation rule added to list
- I'll keep K9.3 but make a box as well? Again sometimes having it in writing for additional parts stops confusion

Thanks for your help. I've added a number of things to my list, I'll wait and see what other suggestions people come up with before i draw up the 2nd draft. If anyone comes up with other suggestion against yours we will have to discuss.

Luke

cdsavage
cdsavage
19
Joined: 25 Apr 2010, 13:28

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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K3.5 - Why the 450 and 300 dimension limits? I dont think they are necessary.
I kinda agree. The only reason i put it in is because last year the challenge was loosely on the f1 regs, this year we have our own rule book so where the sidepods must essentially start isn't defined (f1 regs define it because of the side impact structure i believe?).
Side impact structure makes sense, I would suggest that the inner width dimension is redundant though (300). If anything there should be a minimum outer width, though I think it would be fine without one.
K4.3
- I agree 40000 may be to big, but I think 6000 might be to small. Let me look into it more against my 2013 model
- Will be changed to: "Parallel to and at a distance 100mm forward of section CC" ?
- Whilst it is defined it must lay essentially on top of the tub, I put those restriction in purely to prevent possible exploits. There would be nothing stopping people doing a very tall and thin face for example.
Keep in mind that the bottom of that face isnt lying on the top of the tub, it is lying on the top of the cockpit template, which is in line with the top of the side padding. I agree on adding a width or height constraint, you dont need both though. Max height + area is enough.
K4.4
We need something to force the creation of the side head rests. Maybe I've got myself confused?
The cockpit template includes the area for the side head rests. If you state that the cockpit template must be enclosed in bodywork then 4.4 is redundant.

This is what the cockpit template looks like -
Image
- Your right i've missed that, I will add that in now as it is stated in 3.7.8. Obviously if someone thinks of a better way of writing it we'll change it:

"Only a single section, which must be open, may be contained within any longitudinal vertical
cross section taken parallel to the car centre line forward of a point 150mm ahead of the front
wheel centre line, less than 250mm from the car centre line and more than 125mm above the
reference plane."
I can add a box for that volume, so at least you can remove the part defining the dimensions.
K6.1
- Looking back 6.1 is governed by the main volume anyway so can be removed
- Good idea regarding 10-20mm (added to list)
- Good spot regarding chord (added to list)
In the file I sent you I removed the rear wing volume from the main bodywork volume and added it as a separate box. I would keep 6.1 as you had it but with the addition of the guide box with the dimensions (or instead of them).

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Side impact structure makes sense, I would suggest that the inner width dimension is redundant though (300). If anything there should be a minimum outer width, though I think it would be fine without one.
I haven't got any intentions of adding this in, it was more my reasoning for defining an area where the sidepod inlets must lay (and as such where the sidepod will start)
Keep in mind that the bottom of that face isnt lying on the top of the tub, it is lying on the top of the cockpit template, which is in line with the top of the side padding. I agree on adding a width or height constraint, you dont need both though. Max height + area is enough.
The cockpit template includes the area for the side head rests. If you state that the cockpit template must be enclosed in bodywork then 4.4 is redundant.
I think here i have got confused. Is the cockpit template defined in your file (at work so can't look at the moment)? Because, the headrest rules i was essentially trying to create this.
I can add a box for that volume, so at least you can remove the part defining the dimensions.
Add a box. I'll keep the dimension in just so people can tie the rule book up with the rule boxes (if that makes sense)

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

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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good to see the hard work going into 2014 :)

one question, once the rules are finalised, would someone be able to produce some 2d drawings like the ones in the FIA appendix?
I know we will have the regulation boxes in a file, its just I find things a little easier with the 2d drawings for reference as well. If it cant be done, no worries, I will just pester Astra via PM every 5 minutes :mrgreen:

wigglez28
wigglez28
0
Joined: 14 Oct 2012, 15:26

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Image just thought this might be useful when writing the regulations. This is the 1st image i've seen of what the 2014 noses are likely to look like in any detail. Not the best looking things :/ I'm not sure if the front wing is 2014 spec or if it's just the nosecone.

astracrazy
astracrazy
31
Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Ric:

I'm sure it can be done. We will get the rules finalised and create the 3d boxes and I'll make some 2d drawings as well

Wigglez:

The rules as they stand are identical to the f1 2014 nose rules, so the image you have attached is possible


astracrazy
astracrazy
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Joined: 04 Mar 2009, 16:04

Re: F1 model CFD Challenge (Khamsin Virtual Racecar challeng

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Spec Engines

Instead of there being just one spec engine there will now be multiple. Most likely 2. Some people have made some engines already and it would be a shame not to allow them.

If you have created an engine and you would like to put it forward to be one of the supplied spec engines, please pm me. All engines will be checked to be of similar size - hopefully there will be positives and negatives between each one