Quote:
Originally Posted by JackMcCornack
Racer comfort is different from street comfort. I'm sure everyone concerned--including the drivers--was more interested in the records than in comfort.
One thing that's missing in all the promo pieces (that I've found) is pics with a driver inside, and all the driving videos are edited to obscure the driver. The car has 7/8 the frontal area of the standard Opel Speedster and it has all come out of the cockpit. After a couple of hours in the driver's seat going round and round a racetrack, a GT-40 would feel like a limo. But I want one anyway.
Christ wrote...
> I might be pissing in the wind here, but I thought you could get away with
> almost any size model as long as it was scaled properly and proportionate
> to the full-size chassis?
Pissing in the wind isn't too bad if you do it downwind. I've always wondered why that phrase is never qualified, e.g. "...into a quartering headwind."
Re the model size, my background (such as it is) is small aircraft design and all my testing has been full scale. I'm not going to have any measuring equipment, I'm going to be limited to tufts and maybe oils, I'm looking for how simple it can be and still keep flow attached back to the tail. I'm suspecting the front half will be fairly easy, but from the cockpit back will be challenging. If I can get most of the failures out of the way with quarter scale models, that would sure be a time saver.
PS--my car in the first post? It's 41 inches tall with 5" of ground clearance.
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Normally, I'd want to be pissing
from upwind, so that the result was a urine stream which went downwind. Though I assume that's what you meant.
Of course, the actual phrase is "Pissing
into the wind", which suggests that one is doing the opposite of what's desirable, but I digress. (Quite often, actually.)
Unfortunately, I don't know enough about aero testing to really give an accurate answer that's anything more than a guess about whether a 1/4 model will give you a good estimate of Cd or not.
I can say, with great confidence, that if it were me, I'd make the 1/4 or 1/3 scale model and tweak it for the best design, then scale it up, hoping for the best. I can't imagine that even small intrusions to the flow stream (outside the boundary layer) will cause enough of an issue to really be an issue. Besides, your design doesn't appear to have too many things hanging out in the breeze, so to speak.