Over and Under or around the sides

[Richard]

Brilliant news! Thanks for updating us.

[Carlos]

Congratulations on the Championship Luke, I've always admired the team's grit and tenacity.

[autogyro]

Great News, you must justify sponsorship to a decent level now surely.

[greenpower dude reloaded]

Haha! Yes, funny the way the world works, you spend years (and £1000's) toiling away in a garage then when you give up you start to get people/companies come forward to offer you some form of sponsorship. I've got a meeting later this week to discuss moving this project on further... Not sure I want to but I'll keep you all posted

[autogyro]

I know the feeling GPD, I have been trying since 2009 to progress electric open wheeled racing and find investors and sponsors for teams.
Dont give up now, you should be over the hill, dont forget electric is the future, not if when.

[amc]

Fantastic achievement, well done! Even if you do think it's time to move on, you've achieved some pretty momentous things in the time. You've certainly made an impression on me, as I started taking part in the 'junior' version of the series last year and I have a lot of respect for what you've managed to do. I know how hard it is!

I have a question though:

Is it better to direct air over and under the car in a cambered aerofoil (60mm ground clearance) or is it better to direct it round the sides? (29th December, 2005)

So, 7 years on, what do you think?
You seem to have converged on something that's a little bit of both, except with a really low ground clearance, which I think is interesting... before we started I'd have gone 'over and under' in a heartbeat - instinct told me that the car could be lower than it was wide, and that over-under meant moving the air less. In theory, everything seems to point to this being better, apart from ground effects, which appear more significant than I thought they would.

I'm interested to know what people think, but I reckon the really low and 'tidy' splitter area and floor was the key to your car - among many other things obviously - but for me that stands out. It's not just the low ground clearance, but the fact that no air is encouraged into the floor to disturb the boundary layer probably helps too - other cars with higher gc but too much air going into the underfloor (like ours ) don't seem as efficient... which leads me to conclude that some combination of flat low floor and 'round the sides' is best - but that's tricky to package up (with wheels in the way etc). For that reason I think some of the air should be directed over the top of the car, with the majority going around - possibly a 2:1 split would be best. It's then about managing the flows by creating as few disturbances along the top and sides as possible, and joining them all together again at the back, IMHO. (I made that sound so much simpler than it is ).
In short - do you think you have the best 'concept' in terms of splitting the air different ways, or what would you do differently?

P.S. it's probably an old discussion now, but we've just had a belt drive quoted at 98% efficient from here.

Best of luck with whatever you decide to do with the project Luke!

[greenpower dude reloaded]

Good point AMC maybe it's time for a few conclusions (although I will never stop designing something better in my minds eye)

Over and under or around the sides? Around the sides where possible, I kind of feel almost foolish for questioning this. Over and under throws the air in to some horrible places. It doesn't matter whether you're looking at the path of air flowing over or underneath you have either the cockpit or the ground. Of course, air will flow over the body just about everywhere so we've optimised it for that.

You may have noted that our ground clearance isn't as low as is often perceived. We run at around 60mm off the deck but have skirts down the side which fair in the wheels AND seem to ensure a smoother, more controlled underbody flow.

I don't think the optimum will ever be hit, which some might say is pessimistic but seeing as it's the development that I love, I would say that that's optimistic. I don't ever want to hit optimum - there'd be nothing left to do then!

So which team are you involved with AMC?