S2000 Aerodynamics
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From: West Virginia
Just a minor note on an excellent post/thread:
The splitter increases front downforce by taking advantage of the significant positive pressure at the front of the car. That pressure pushes down on the splitter, that's where the big increase in front downforce comes from.
If the only effect was moving the low pressure forward, then it would be a net wash on downforce, as any added to the front would be taken away at the rear.
This was the case with the RX7 R1. The splitter decreased front lift significantly, but the rear wing only countered the rear lift induced by the downforce at the front of the car in front of the front wheels.
The R1 aero mods produced greater drag (.31 vs. 0.29 Cd), but only reduced lift up front.
Which is why it was stupid of me not to remove the splitter before running the Texas Mile with no rear wing!
The splitter increases front downforce by taking advantage of the significant positive pressure at the front of the car. That pressure pushes down on the splitter, that's where the big increase in front downforce comes from.
Originally Posted by robrob' timestamp='1369230496' post='22559302
The graphic below is a comparison between a car with an air dam alone and an air dam with a splitter. Red is high pressure, blue is low. You can see how the splitter reaches out and chops off the bottom of the high pressure bubble on the nose of the car. The high pressure also concentrates on top of the splitter which pushes it downward for downforce. The airdam alone creates a lot of low pressure under the car so adding the splitter doesn't add much more low pressure but it does move the low pressure forward which will put more pressure on the front wheels.
This was the case with the RX7 R1. The splitter decreased front lift significantly, but the rear wing only countered the rear lift induced by the downforce at the front of the car in front of the front wheels.
The R1 aero mods produced greater drag (.31 vs. 0.29 Cd), but only reduced lift up front.
Which is why it was stupid of me not to remove the splitter before running the Texas Mile with no rear wing!
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From: West Virginia
Interesting....I would think that a front splitter angle is critical...suppose the static angle is 0 degrees, but the car encounters a bump raising the front of the car so the splitter is at a positive angle...wouldn't that create a huge amount of front lift of a moment?
Also, can anyone comment on the CR front lip? Why did Honda decide on such an unusual design for a street car?. How much does in increase drag do you experts think?
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I think I vaguely remember some issues people had with riser equipped gtc 200's. u may wanna do some research should u decide to go that route
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Dries, I finally found a wind tunnel test pic with the smoke wand between the car roof and wing. This pic shows very good airflow below this Lotus mid level wing:
Did your study do this kind of testing?
I have added a lot of S2000 specific content to my aerodynamics page.
Did your study do this kind of testing?
I have added a lot of S2000 specific content to my aerodynamics page.
I discussed the "smoke" thing with 2 professors in the instituted when i did the investigation in the windtunnel.
I would have to dive into my paper to be able to give you the correct answer, I'll try to find it in the attick the coming days, i don't have the paper digitally anymore.
To be able to test a full scale car in a windtunnel, you need a very very big diameter of tunnel to avoid a certain effect when the walls of the tunnel are too near your testobject. There are only a few tunnels of this size in the world.
To do some tests you need to scale down your object and adjust the windspeed to see the same effect around your object. Therefore I worked with a scalemodel in the tunnel available. I remember we couldn't work with smoke because we clearly wouldn't see the smoke because of the air flowing too fast.
I was told the all the pictures of smoke in a windtunnel on a car are only for promotional issues, because with the airflowspeed you need to obtain a justified result, the smoke gets invisible... If i remember correctly, the smoke is visible on low speed airflow, so it gives you an idea of the air flowing around the car. But you need a certain minimum speed to have the "wing lift" effect like on airplanes, and at this speed you can't work with smoke anymore and you have to work with some fluid put ont he model or small vertex ropes glued on the model.
Like this :
I feel like a student again thinking about these days.... and much younger!
Oh, i just noticed some ropes in your picture as well!
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Seriously?! One of the brightest guys on this board? Mr. Aero himself?!
I'm laughing with you, not at you!
I'm not gonna tell you when I first noticed it.....
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From: West Virginia
In my defense the side view on my car is blocked by the big wing end plates and the overhead is blocked by the wing. My wife had her S out today and I noticed it and snapped the pic. I had no idea the brake light stuck out like that though. 
Kudos to Honda 
Kudos to Honda
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