Windshield separation bubble revealed in tuft testing (on MGA; none on Geo Metro)

[MetroMPG]

Just thought this was interesting.

Modern cars have attached flow - no entrained vortex / separation bubble - at the base of the windshield. Hucho made a point of mentioning that even the relatively steep VW Golf mk 1 windshield had no separation at its base.







Source: Wind tunnel testing of the MGA

[Bicycle Bob]

R & T was much amused to see air going in through the hood "out" vents when that study appeared. However, it was probably an improvement on the gorgeous TF model, for aero. BTW, the MG B was styled by chopping the front and back off a pumkin-seen salt flat special they had done well with.

[MetroMPG]

Yes, the text of the page linked in post 1 is definitely worth reading. They discovered a couple of funny & interesting aero traits about the car.

If I were made of money, I'd suffer poor aero to have a lovely car like this to tool around in occasionally.

[MetroMPG]

Also: I like how they put paper behind the windshield in the top photo to ensure they got a clear image of the tufts on the glass.

[Piwoslaw]

Originally Posted by MetroMPG

Also: I like how they put paper behind the windshield in the top photo to ensure they got a clear image of the tufts on the glass.

"DO NOT TRY THIS AT HOME"

[jamesqf]

And if I had an open-source CFD program, and the skill to create the numerical models of car shapes, I'd love to start with a basic sports car plan, and optimize the aerodynamics as much as possible without making it not be a sports car.

[jime57]

I owned MGA's in the late 50's and early 60's. It wasn't that great a car. Obsolete engine design and far too much body roll when pushed. I did look good.

[jamesqf]

Yeah, but look at what the competition had in the '50s & '60s: tailfins and trunks that you could convert to 6-person hot tubs.

I guess I was a proto-ecomodder even back then. We had an old '59 Chevy (with the tailfins that curved over horizontally) as a second car when I was a kid, and I remember that I kept thinking the car would be so much better if I could just whack off everything aft of the rear wheels, and taper the body back...

[Frank Lee]

Originally Posted by jamesqf

Yeah, but look at what the competition had in the '50s & '60s: tailfins and trunks that you could convert to 6-person hot tubs.

Gee, you say that like it's a BAD thing!



Is a small car hot tub OK?

[jamesqf]

Originally Posted by Frank Lee

Gee, you say that like it's a BAD thing!

Well, yeah, if you like to go fast around curves without sloshing :-)

Or to use my favorite (stolen from Donald Westlake) descriptive phrase for SUV handling characteristics: "Gee, it drives like a waterbed",