windshield airflow

[Maillemann]

Originally Posted by Lug_Nut

Yeah, I know. It will just fill up with snow...
Oh, It'll also obscure my state's annual inspection sticker...

Indeed, both these things occured to me, as well as the invariable attendant accretions of leaves and pine needles. I agree from this standpoint they are less than ideal, but I'm still curious about their effects on aerodynamcs, be it positive or negative.

[lunarhighway]

just think of how cool it would be to have this colosed of with a lid that electrically opens when the wipers are activated... or maybe just the whole fairing folding against the window

extra weight and electrical load from such a setup would probably cancel out the benefits but than again there was a time when every sporty car seemed to have pop up headlights so who knows?

anyway so far i've installed flatblade wipers a while back... so i'm a littel less eager to shield them from the airflow

they look really sleek although at low speeds they don't quite deliver enough pressure on the blades... i might have to tweak my arm's ... to bad they still attach to the center of the blade... would be cooler to have wiperblades/arms in one single piece flat piece. jugeing from the rainpatterns they do have an effect on the airflow when not in use, but i haven't been able to see their effect in my FE

[zpiloto]

Originally Posted by Maillemann

You mean something like this, right?



(Lund Wiper Cowl)

I've wanted to put one of these on a vehicle for years, but will have to fabricate my own since they're mostly made for trucks. Not a big deal, used to working with thermoplastics, but have always wondered if it's a benefit or detriment to airflow. Visually seems like an obvious improvment, but could that big gap that's being created just cause more turbulence? Anyone know?

That area is dead space with the angle of most windshields. Because of the turbulence the wiper drag in not going to be noticeable. I did a couple of runs with a shield like the one on the truck except mine went straight to the windshield, no gaps, without any noticeable increase in FE. I figured the use of wipers was more important. I think if you really wanted to increase the FE you need to put a wedge from the front of the hood to about 6" up the windshield.

[cfg83]

zpiloto -

Originally Posted by zpiloto

That area is dead space with the angle of most windshields. Because of the turbulence the wiper drag in not going to be noticeable. I did a couple of runs with a shield like the one on the truck except mine went straight to the windshield, no gaps, without any noticeable increase in FE. I figured the use of wipers was more important. I think if you really wanted to increase the FE you need to put a wedge from the front of the hood to about 6" up the windshield.

Would this be a situation where a "hood lift" would help, i.e. where spacers lift the rear of the hood up? If 6 inches is too high for you, you could compromise between lift and style, and reduce the drag of the wipers. But I think you would need to fill in the triangular gap that is created on each side between the fenders and the hood.

CarloSW2

[zpiloto]

Originally Posted by cfg83

zpiloto -



Would this be a situation where a "hood lift" would help, i.e. where spacers lift the rear of the hood up? If 6 inches is too high for you, you could compromise between lift and style, and reduce the drag of the wipers. But I think you would need to fill in the triangular gap that is created on each side between the fenders and the hood.

CarloSW2

Mine opens from the front. It would be beyond my capibilities to lift it. Yes you would need to fill in the sides. I don't think this would be more than a 1-1.5% increase at best. I'll save that for when I get the mileage up to Little Blue country where I can see the effects.

[Lug_Nut]

Originally Posted by cfg83

Would this be a situation where a "hood lift" would help, i.e. where spacers lift the rear of the hood up? If 6 inches is too high for you, you could compromise between lift and style, and reduce the drag of the wipers. But I think you would need to fill in the triangular gap that is created on each side between the fenders and the hood.
CarloSW2

"Dropping" the front is more effective than raising the rear.
Re bumper removal: I had at some point of time a Civic 1200 (not the CVCC) with a mangled front bumper. The center was pushed back which made the ends stick further out (a reversed train's 'cow-catcher') to the point that it failed the safety inspection. I removed the bumper. Then it failed because of the brackets as "theClencher"s did. I just removed the offending brackets, too. It then passed with no problem.

[GasSavers_BluEyes]

Originally Posted by cfg83

Would this be a situation where a "hood lift" would help, i.e. where spacers lift the rear of the hood up?

You would have to also make a way to re-seal the rear of the hood to the cowl after lifting it. Otherwise, you've just made a great route for air to go under the hood and out the bottom of the engine bay under the vehicle. Very ugly airflow path there.

[cfg83]

BluEyes -

Originally Posted by BluEyes

You would have to also make a way to re-seal the rear of the hood to the cowl after lifting it. Otherwise, you've just made a great route for air to go under the hood and out the bottom of the engine bay under the vehicle. Very ugly airflow path there.

Ooof, I was hoping that gap would be benign. The "triangular" side shape is easier to build than the more complex (curved and styled) shape of the rear of the hood.

CarloSW2

[BamZipPow]

Originally Posted by lunarhighway

just think of how cool it would be to have this closed off with a lid that electrically opens when the wipers are activated... or maybe just the whole fairing folding against the window

extra weight and electrical load from such a setup would probably cancel out the benefits but than again there was a time when every sporty car seemed to have pop up headlights so who knows?

It would be easier to make it with a cam based using the wiper motor to open/close the fairing. When you activate the wipers, the cam would push the fairing up just enough to allow the wipers to clear. When turned off, the cam would allow the fairing to close after the wipers have retracted.

One might even incorporate a clear lightweight fairing onto the wiper arms themselves...kinda like the transformers movie.

[basjoos]

Here is the windshield wiper windscreen that I installed on my car. My wipers were definitely in the airstream, a fact made evident when driving in fog where the moisture would deposit on the lower windshield in a pattern reflecting the wipers upstream.