CW Racing Posted December 13, 2011 Author Report Share Posted December 13, 2011 (edited) i have a small simulation running on my laptop to show the wing in yaw. this will be very rough but it shows the principal well, my big pc is still plugging away on the other sim Edited December 13, 2011 by CW Racing Link to comment Share on other sites More sharing options...
Adex Posted December 13, 2011 Report Share Posted December 13, 2011 Jamie but is that not because your running without end plates and so the air gets lost over the edges and doesn't 'push' down as it will take the easiest route. In the centre of the spoiler it doesn't really have this choice.... I remember watching a great TV program about the new airbus recently. It was full of non-laymen tech-speak so was on pretty late, but the gist was this. On an aircraft, up to 30% of a wing's surface provides little or no lift due to the low pressure air travelling at high speed 'spilling' over the edge of the wing tip. By experimenting with different shape 'winglet' or 'shark-fins' they were able to interupt this spillage, significantly increasing the wing's efficiency. In practice, this led to the engineers being able to reduce each wing's surface area by around 25%. As lift & downforce are pretty much yin & yang, you may find this interesting &/or useful. http://en.wikipedia.org/wiki/Wingtip_device Link to comment Share on other sites More sharing options...
CW Racing Posted December 13, 2011 Author Report Share Posted December 13, 2011 (edited) so here is another wing with the flow comming in at an angle. you can see if the end plate is to big it blocks the wing. big areas of turbulant flow Edited December 13, 2011 by CW Racing Link to comment Share on other sites More sharing options...
Adex Posted December 13, 2011 Report Share Posted December 13, 2011 So maybe an aerofoil shaped winglet is better then? Link to comment Share on other sites More sharing options...
PjMetalHead Posted December 13, 2011 Report Share Posted December 13, 2011 [quote As lift & downforce are pretty much yin & yang, you may find this interesting &/or useful. http://en.wikipedia..../Wingtip_device not to be confused with... http://en.wikipedia.org/wiki/Toyota_Winglet Link to comment Share on other sites More sharing options...
benjiboy87 Posted December 13, 2011 Report Share Posted December 13, 2011 very interesting read...learning quite a bit. But can someone tell me if the high rise spoiler on the 205 actually make a difference? i mean in the way it is angled and shaped? what sort of pressure and drag does it create and effect the way it handles being 4wd Link to comment Share on other sites More sharing options...
Adex Posted December 14, 2011 Report Share Posted December 14, 2011 Good question. I'd always thought that the side parts of a GT4's high-rise spoiler were strangely shaped. Given the fact that if you compare the distance between the two leading edges of each side to the trailing edges, the gap narrows by quite a lot. Aerodynamically, surely this 'bottleneck' is counter-productive? Or is it purely because the low-rise spoiler is that shape (due to the contours of the bootlid), so the riser blocks have to be? Link to comment Share on other sites More sharing options...
CW Racing Posted December 14, 2011 Author Report Share Posted December 14, 2011 So I would agree with that statement. The high rise arrangement is the shape it is because the low spoiler is the shape it is. One has to lead into the other. Not to say it isn better though. Notice how the TRD spoiler is a parallel section that is adjustable. Link to comment Share on other sites More sharing options...
Adex Posted December 14, 2011 Report Share Posted December 14, 2011 (edited) Thats why the TRD and in fact the HIRO spoilers have quite a pronounced 'waist' curve in order to bring the tops more into parallel with the cars centerline. Good for aero, bad for styling it seems? (Apologies to all who have TRD & HIRO spoilers, I'm sure you love them really). Since watching that show about the airbus, I'm convinced that winglets are the way to go. I'm surprised more teams haven't experimented with them yet. Edited December 14, 2011 by Adex Link to comment Share on other sites More sharing options...
CW Racing Posted December 14, 2011 Author Report Share Posted December 14, 2011 (edited) Are you talking about the little flicks on the wing tips?? That fact you dont see winglets as you call them on race card isn't because they havnt experimented with them. It's usually because of regulations. Our le mans regs say there must be a vertical end plate of a given surface area when viewed from the side and it leading edge be radiused 5mm rads all round. And be parallel in section through its body. Edited December 14, 2011 by CW Racing Link to comment Share on other sites More sharing options...
Adex Posted December 14, 2011 Report Share Posted December 14, 2011 Damm the regs! :xmas_sad: :xmas_laugh: Do they allow what I've heard referred to as 'fences' or 'gates' along the top like this maybe? Link to comment Share on other sites More sharing options...
CW Racing Posted December 14, 2011 Author Report Share Posted December 14, 2011 Yep that looks like a scooby wing. Idea of these is to try and straighten the car when it jumps. You see it more on rally cars and Dakar trucks. We did it on the Nissan we built some years ago. I will try to find some pictures. The idea with a swept wing on an aeroplane is because you get 'flow migration' across its length, due to the angle you put these ribs or flow straighteners in place to limmited the effect. Link to comment Share on other sites More sharing options...
CW Racing Posted December 14, 2011 Author Report Share Posted December 14, 2011 Link to comment Share on other sites More sharing options...
InsolentMinx Posted December 15, 2011 Report Share Posted December 15, 2011 finally, a technical topic that i actually find interesting and can kinda understand :D very interesting stuff Link to comment Share on other sites More sharing options...
CW Racing Posted December 15, 2011 Author Report Share Posted December 15, 2011 Chip in anyone with any questions or opinions on what we are on about. Link to comment Share on other sites More sharing options...
CW Racing Posted December 15, 2011 Author Report Share Posted December 15, 2011 So everyone…. Welcome to part 2 of my aero class lol… I finally managed to get around to finishing my study with the wing and its end plates in place… Again this is exactly the same wing but with end plates added as the design of our le mans car. The air flow is as 30m/s as before. We have left the scales of the pressure plots and the flow lines the same so there is a good comparison. Picture 1 top view with pressure plot Picture 2 lower view with pressure plots Picture 3 top view with flow lines Picture 4 lower view with flow lines the results are for this wing a downforce number of 527N (52Kg) with drag force of 86N (8Kg) so it has a L/D of 6.12 so thumbs up!!!!! Link to comment Share on other sites More sharing options...
craig87 Posted December 15, 2011 Report Share Posted December 15, 2011 BUT how does that compare to smaller end plates? I.e is the massive lower part of the end plate necessary? I guess you need to see airflow from the car to answer this? Link to comment Share on other sites More sharing options...
CW Racing Posted December 15, 2011 Author Report Share Posted December 15, 2011 im working on that... i have a summery to post on this to finish the general principals bit of what end plated do then im going to try and put a car shaped blob in front of the wing Link to comment Share on other sites More sharing options...
soulja_raj Posted December 15, 2011 Report Share Posted December 15, 2011 Cracking work, keep it up. What program are you using if you don't mind me asking? Looks interesting, i have only used Pheonix simulator when i was at uni, but some aspects of that program was limited. Link to comment Share on other sites More sharing options...
CW Racing Posted December 15, 2011 Author Report Share Posted December 15, 2011 i use ansys and floworks/cosmos... Link to comment Share on other sites More sharing options...
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