Coastdown tunnel - The secrets of Laurel Hill revealed

[Caito]

I think this reading might be really interesting. It definitely was to me.


http://www.racecar-engineering.com/arti ... urel-hill/



Comment.-

[Tim.Wright]

Very cool, though Id be interested in how they measure drag and downforce. I would tend to think that it would be hard to measure these forces as accurately as a sting in the wind tunnel would.

On the other hand the results should be more accurate because the environment is closer to a real racetrack.

Tim

[Caito]

They measure drag with coastdown. Downforce, don't really know. Height sensors maybe..

[Jersey Tom]

Nothing to see here. Move along, move along.

[Caito]

Is that your new team, JT... ?

[Formula None]

Just needs a turn.

[flynfrog]

The tunnel is pretty cool. We used coast down test in college since we didnt have access to a wind tunnel and our Colorful fluid dynaimcs skills left something to be desired. You can learn a lot from just a few sensors.

[Jersey Tom]

Nah, not my team. Just not anything super fancy. Coastdown testing is pretty straightforward and popular at many levels.

Nice to have your own secluded tunnel for it though I guess.

[marcush.]

A scale tunnel with belt etc is never ever going to give you the results alone.You are working in a set of constraints that will inevitably reach it´s limits simply because the variables are too many and you are testing too far away from real world figures.The big advanatge should be the repeatability of the testing.
A real tunnel at least does away with scale effects and the crook of having a moving belt.You will surely be able to derive a very good aeromap with some preparation (hydraulic jacks to adjust rideheightsprecisely and of course precise rideheight measuring.
A circular or oval tunnel would be the the best ,wouldn´t it? That would have been a nice addition to MTC I´d think.But unfortunatelly nobody told Ron.
security is an issue admittedly.But it would be ulta accurate even when the driver will collapse sooner or later going round and round...

[Caito]

Going round you are at a constant yaw. Wouldn't that affect the thing? Probably a long straight, half circle, etc would be better.

[Pandamasque]

So what MTC needs is an underground superspeedway or does that count as testing?

[FW17]

That should be costing the same as a wind tunnel

High banked circular track like this with a enclosure

[Formula None]

[youtube]http://www.youtube.com/watch?v=s-f_0z3H ... r_embedded[/youtube]

[marcush.]

no not banking you want slip angle you want yaw as this is when you need the downforce ,right?.
The big advantage compared to a Winddtunnel is the running cost.To move the air is really expensive isn´t it?

you would not need a winddtunnelmodel or you could run it as a RC car ... in the same tunnel if you wanted....

The data would be really representative of real world figures wouldn´t it?

[FW17]

Team looking for a tunnel?

Team Lotus

Closest tunnel?

110 mile, Withcall Tunnel, Lincolnshire, U.K. 1 mile long