[KVRC] SR71 2016

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SR71
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Re: [KVRC] SR71 2016

Post by SR71 » Sun May 01, 2016 9:21 am

CAEdevice wrote:It is funny: none of the car mentioned above has aero development (one of them does not exist at all), except for drag reduction for Tesla.

On the contrary, Formula E, that is a real race car, with basic aero performance, seems to have radiators.

https://encrypted-tbn0.gstatic.com/imag ... tUE46581D2

http://current-e.com/wp-content/uploads ... ooling.png

Anyway: cooling added realism and made the design more interesting in KVRC, but a good project in 2015 is still winning in 2016 (with advanced cooling). See MantiumRay for example.

Will we see you at the Nurburgring or in Monaco?
Formula E isnt really the benchmark in electric technology. I specifically didnt mention them for that reason.

A fully charged Tesla would most likely win against a Formula E car with 4 passengers and no need to switch cars during the race. And even Tesla's arent the benchmark. F1 for instance has the most advanced batteries of non-military vehicles, only Koenigsegg has them in a production car. They are still quite heavy though - but that will change soon enough.

At the end of the day, electric = less cooling.

CAEdevice
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Re: [KVRC] SR71 2016

Post by CAEdevice » Sun May 01, 2016 9:24 am

Are you joking? A Tesla S weights about 2200kg... nothing to do with Formula E handling (with similar power/weight ratio).

wesley123
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Re: [KVRC] SR71 2016

Post by wesley123 » Sun May 01, 2016 11:56 am

SR71 wrote: At the end of the day, electric = less cooling.
Afaik the batteries used have a smaller operating temperature than a good ol' ICE and are much less capable of dealing with high(er) temperatures.

the Tesla Model S used as an example still has a pretty big radiator.
"Bite my shiny metal ass" - Bender

machin
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Re: [KVRC] SR71 2016

Post by machin » Sun May 01, 2016 7:44 pm

In race mode Formula E is limited to 170kW... The current KVRC cars have well over twice that, so the cooling flow requirements would end up being >~2x higher than a current formula E if we were using similar electric technology, even taking into account our higher speeds we would still need considerable cooling apertures and heat exchangers. I think it adds an extra dimension to the challenge which is good for any budding automotive engineer to tackle.
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machin
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Re: [KVRC] SR71 2016

Post by machin » Sun May 01, 2016 7:54 pm

CAEdevice wrote:Are you joking? A Tesla S weights about 2200kg... nothing to do with Formula E handling (with similar power/weight ratio).
Not to mention this minor short-coming:
Autocar Magazine wrote:. But we couldn’t complete one flying lap of the dry handling circuit before the battery, inverter and electric motor tripped into safe mode and cut peak output by at least 50 per cent.
Oops. I hope those 4 passengers like walking... ;-)


But seriously: it would be cool to see your car compete: it does look very nice!
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SR71
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Re: [KVRC] SR71 2016

Post by SR71 » Sun May 01, 2016 11:15 pm

machin wrote:
CAEdevice wrote:Are you joking? A Tesla S weights about 2200kg... nothing to do with Formula E handling (with similar power/weight ratio).
Not to mention this minor short-coming:
Autocar Magazine wrote:. But we couldn’t complete one flying lap of the dry handling circuit before the battery, inverter and electric motor tripped into safe mode and cut peak output by at least 50 per cent.
Oops. I hope those 4 passengers like walking... ;-)


But seriously: it would be cool to see your car compete: it does look very nice!
Oh youre referencing those 4 year old tesla reviews? yeah, those were interesting a long time ago however not really relevant to anyone with knowledge of the actual car.

The P85 (discontinued) would easily handle a FE car given it's advantage on the straights. The P90 would be no competition at all. The P100 has leaked and should be the new benchmark in electric performance sedans (yes i said sedan and yes it makes an FE car look pathetic in a straight line).

FE is painfully slow. Yes you're right that a tesla is heavy. Yet it out accelerates a FE car by such a margin that its weight in the corners can be offset on the straights. Plus - it can do those accelerations all day long and still do 200 miles on a charge. How much time is lost in the pits changing "cars" by FE?

This is all pointless though since you'v seemed to miss my point that I desire KVRC to be a futuristic competition (at least 10 years) and talking about electric technology now is completely pointless given the change the industry is going to go through. It's quite clear that electric racing will soon over take petrol, even with the points I made above I fully support FE, they made a great choice to keep it low cost for the first few seasons and hence the low performance. But there is no doubt electric will be the new racing benchmark soon enough.

If you can't see that point then lets end the discussion. Thanks for the compliments on my car though - it was fun to build.

SR71

machin
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Re: [KVRC] SR71 2016

Post by machin » Mon May 02, 2016 8:54 am

I think in future years we probably will continue to play with the mechanical requirements, which will undoubtedly see changes to the cooling flows (I have my doubts we would ever see a complete eradication of cooling though!). But for now I think it is good to include them as we have a number of entrants who are current mechanical engineering students who will soon be designing equipment for the real world, and that means they will need to take into account cooling flows. But as you say: it is what it is and no point arguing over it. :-)
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