Khamsin Virtual Racecar Challenge 2015

[RicME85]

Its a shame there is no scope in the rules to be able to do a front engine car

[CAEdevice]

Its a shame there is no scope in the rules to be able to do a front engine car

Yes, I considered a 50/50 weight distribution instead aof 40/60. To be honest there are no advantages in such a configuration... except the elegance of general shape

[LVDH]

Cool car! The only downside I see is your exhaust positioning. The driver might complain. Why not in front of the front wind shield?

I took the time to plot L/D for all of the cars:

... my main problem is CoP position.

Look, with that L/D, just remove your rear wing. You will surely have much less drag, the car might be balanced and you are all set.

I was about to ask anyways what you guys think about removing the rear wing?
So far my investigations show that it is a 50/50 choice but every time I removed it the base design was horrible so it is still difficult to judge for me.

I could still bite myself as just moving my CoP 2cm further back I could have won the race. 2cm!!! between winning and loosing!!!

To make matters worse some dumb employee must have taken his smartphone to the virtual wind tunnel and leaked the footage of the new car:

[CAEdevice]

Hi LVDH, as usual, your posts are very interesting.

Cool car! The only downside I see is your exhaust positioning. The driver might complain. Why not in front of the front wind shield?

Yes, I didn't have the time to change the aero concept. I'll probably make the exhaust blow into the dissuser in the next release.

I took the time to plot L/D for all of the cars

Wich L/D race do you expect for the next races? Better o worse ration than during the high downforce races? Will the best car still have a 4.5 ratio?

To make matters worse some dumb employee must have taken his smartphone to the virtual wind tunnel and leaked the footage of the new car

Are you going to fire him?
Nice car, it seems an evolution of the latest one.
Are you using Xflow? Very interesting and not conventional software!

[LVDH]

Wich L/D race do you expect for the next races? Better o worse ration than during the high downforce races? Will the best car still have a 4.5 ratio?

I am pretty sure that it will be much higher as there will not be any crazy devices to produce just that little bit of extra down force at any cost anymore. So we should see values better than 5.0

Nice car, it seems an evolution of the latest one.
Are you using Xflow? Very interesting and not conventional software!

Well, as I cannot change my brain I have to try different tools to finally win.
For the first race I finally took the time to learn Blender better. The second race was about creating a very efficient OF setup and I used OpenMDAO to a certain extend to develop the wings.
This race CAESES was the new tool.
Now the tool of choice will be XFlow.
For the following race I hope I will have in internally developed tool ready.

[CAEdevice]

Well, as I cannot change my brain I have to try different tools to finally win.

I can understand. Since I can't change my brain and I have only one tool, I try to bring fresh air designing the front engine version of my car

[cdsavage]

Out of interest Chris, are the COP numbers the "actual" or "KVRC corrected" figures?

These are the corrected numbers.

Now "naked" pictures of the top teams this time??

Unfortunately I don't have access to the full simulation results for this round, so I'll see if I can find something else to post.

The front engine concept looks great. If the 2016 competition goes ahead with a continuation of the current rulebook, it would definitely be worth considering options for allowing front-engined layouts.

[AratzH]

... my main problem is CoP position.

Look, with that L/D, just remove your rear wing. You will surely have much less drag, the car might be balanced and you are all set.

Actually I was thinking of a similar solution for race 4... and some other things...

[machin]

Hi everybody, as I announced after the second race, I prepared a surprise for the 4th race... even if I don't think it could race!
I tried to design someting rule compliant, moving the engine template in front of the footbox template, and moving the cockpit rearwards. The base was my "regular" MP003, the version used during the 2nd and the 3rd race. The Panoz Spyder inspired me too.

What do you thing about?

http://www.caedevice.net/KVRC/MP003_Front-engine.jpg

Yes, I know I would had better to spned my time improving the "official" project, but I need to refresh my ideas

Here are some numbers:

DR: 1950N
DF: 6800N (I've run only two test to optimize it)
COP: 1.5m

For a bit of fun... I adapted the Virtual Stopwatch base car to represent a front engined car with 50:50 weight distribution and ran your numbers:-

Nurburgring lap times:

Assuming that it is RWD: 379.133 seconds
Assuming that it is Front WD: 400.195 seconds

Now...if we use the downforce and drag figures from that model, but assume the COP is 1.65m and the weight distribution is 45:55 and it is RWD (i.e. the standard KVRC car) we would get a laptime of:

377.158 seconds

The moral... Front wheel drive only doesn't really "work"... (despite what Nissan might want you to think!)
With RWD you get an advantage from running a slight rear weight balance (and therefore downforce balance too)...

My own Westfield racecar was (I sold it a couple of years back) front-engined RWD... but I worked really hard to reduce weight at the front and move weight backwards... so I fitted a lightweight radiator and fan, smaller headlights, alloy cylinder head, Dry sump with the sump tank in the passenger footwell, battery in the passenger area, carbon fibre bodywork at the front.. and with driver onboard got it to around 46:54 front:rear mass distribution... was quite pleased with that.

[variante]

Nice fight for P1; I did hope for a victory from Mantium (championship wise...), and the preliminary results seemed to confirm my hopes. Unfortunately, I had to surrender to reality.

As for my side, not everything is lost. Luckily I managed to stay on the podium, and I might have a car ready for the following races. Maybe.

The front engined car is intriguing. It looks good and may be a challenging base to develope. I fear, however, that only the regulations could determine which of the two engine layouts would edge the other, as it would be pretty difficult to balance the two choices...

LVDH, if you've got all those problems with the front wing, I don't see why you wouldn't take advantage of the situation and get rid of the rear wing as well!
(Awesome CFD tools you've got!)

BTW, the followings are going to be tight races, given the inevitable design "standardization".

[MadMatt]

I am following the competition from distance and I must say it looks awesome. No way I could have keep up with you guys. Matteo your Batmobile looks incredible, fair play to you! As for the "rest" I cannot wait to see your evolutions, but in a sense I wish we could see more pictures of the cars, as they are all interesting!

[CAEdevice]

For a bit of fun... I adapted the Virtual Stopwatch base car to represent a front engined car with 50:50 weight distribution and ran your numbers:-

Nurburgring lap times:

Assuming that it is RWD: 379.133 seconds
Assuming that it is Front WD: 400.195 seconds

Now...if we use the downforce and drag figures from that model, but assume the COP is 1.65m and the weight distribution is 45:55 and it is RWD (i.e. the standard KVRC car) we would get a laptime of:

377.158 seconds

Thank you machin for adapting the Virtual Stopwatch settings.

The front engined version is still RWD (nothing to do with the Nissan project, that should have the rear electric engines to be complete). The idea of moving ahead the engine takes origin from two reasons:

1) More elegant appearance (personal taste)
2) The presence of a big frontal wing (see my "regular" car, and other, like Variante or Chris preliminar study) gives a big DF at the front and the COP is around 1.5. I think that with a traditional LMP1 design the front engine solution would not work.

I'm going to release the STL file of my front engined car, but not too soon because there are some detail that are exaclty the same of the official car (floor, diffuser, rear wing).

[machin]

To make matters worse some dumb employee must have taken his smartphone to the virtual wind tunnel and leaked the footage of the new car:
http://mantiumcae.com/wp-content/uploads/MR_CP.gif

Nice!

I think that with a traditional LMP1 design the front engine solution would not work.

The thing is... if we went to 4WD then your 50:50 split would work very well... depending on the configuration of the track there would likely be at no disadvantage compared to a rear-biased layout... That is why I still think that the Nissan GTR LMP1 can be an OK solution once they have sorted out the Hybrid system to give them 4WD... I think they should also look at moving the weight bias back from the current 60:40 as I don't see such a bias being very good for the tyres.... and they need to develop a higher downforce package... but that is a separate subject...

There's a couple of minor configuration issues with your layout as it stands: exhaust routing (as pointed out by others) and drive shaft routing: you would likely need to widen the cockpit area if you are sending a lot of power rearwards...

...But I like it!

[CAEdevice]

I am following the competition from distance and I must say it looks awesome. No way I could have keep up with you guys. Matteo your Batmobile looks incredible, fair play to you! As for the "rest" I cannot wait to see your evolutions, but in a sense I wish we could see more pictures of the cars, as they are all interesting!

I'm sure that your car, if evolved, could be on the podium. What about the last race?

[cdsavage]

A few more images of the top 3:



















Championship standings after round 3:

Code: Select all

JJR Racing              68
Variante                58
Mantium RAY             43
CAEdevice               39
TF                      24
Brook Motorsport        16
DynaRace                12
Talno Racing            12
Kineuton                10
DH Racing               8
Pure Power Racing Team  7
Mercury Motorsport      4
sjns-Racing             2

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And a quick look at the changes between the entries for round 1 and round 3:

Code: Select all

                    ΔCL.A           ΔCD.A           Δm from COP=1.65m   Δlap time
Mantium RAY         +89.175%        +18.978%        +0.053              -4.117%
Brook Motorsport    +70.051%        +14.655%        -0.437              -2.069%
TF                  +113.993%       +21.849%        +0.118              -1.384%
CAEdevice           +9.215%         +3.509%         -0.053              -0.907%
Mercury Motorsport  +95.370%        +33.036%        -0.192              -0.816%
JJR Racing          +4.755%         +3.165%         +0.034              -0.361%
Variante            -11.573%        -1.149%         -0.025              +0.995%

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Keep in mind that the COP calculation was slightly different in round 1 for some entries (there was a post on this by Julien shortly before the first round).