Exterior. Mirrors on Cars and drag.

[xelasnave]

I caught bits of the 12 hours race at Bathurst.
I thought that given every little improvement gets you a little ahead of the opposition.
And my thought is to remove the exteriour mirrors and have internal cams of the view one gets from the rear view mirrors.
So would you not think, all other things being equal two identical say Ferrari one with no mirrors one with hitting conrod straight together.
I guess it would result in some difference. I think if if made a difference of five feet at the end of conrod... I wonder the impact.
Alex

[csb]

Just had a look on the net - a few threads quote some research/testing that shows the door mirrors make up 3 - 6% of drag effect on a car. Some say that is significant and more than they would expect.

And car manufacturers already fitting cameras with internal monitors - BMW i8.

[xelasnave]

I better knock the mirrors off my 1200 cc car.
Alex

[75BC]

The architects of the Bugatti Veyron had a few goes at designing the side mirrors on that because of air flow issues. One issue they had was not getting air flowing over the car but into it. The engine itself consumes large amounts of oxygen but it also has 10 radiators to feed air into.

[The_bluester]

One race series (The old British originated Super Tourer category) required the factory mirrors to be retained rather than replaced with something more aerodynamically valid as the series promoters wanted them to get smashed and broken and knocked off the cars in competition so as to add to the crowd pleaser effect.

[AndrewJ]

I always thought the side mirrors were used by racing drivers to gauge when they were getting too close to a wall :-)

Andrew

[The_bluester]

That as well.

[JA]

Yes it would make a significant difference, depending on their size, shape and aerodynamic attributes, but depending on what class they are in they may be required to keep them on for safety and homologation/likeness to original model reasons.

Best
JA

[Shiraz]

go the whole hog and use cameras and screens to replace the windscreen and side glass as well. significantly improve the aerodynamics and aircon efficiency, save weight, make it a lot safer in a prang and remove the need for the teatowel wedged in the sunnyside window when transporting kids. Oh and if you have a Ford, would save a fortune on bi-annual power window repairs.

[Larryp]

I remember reading many years ago-I think the book was "Racing and Sportscar Chassis Design" by Mike Costin and David Phipps-that it requires 6BHP per square foot of frontal area to push a car at 100mph, and 25BHP per square foot of frontal area to push it at 150mph.
So mirrors would definitely affect the car, and much more so at high speeds.
Probably not a great effect at legal road speeds, though.

[Shiraz]

apparently interactions with airflow around the rest of the body are complex and the total extra drag is somewhere between 2-7%, which is a lot more than the area of the mirrors would suggest. http://publications.lib.chalmers.se/records/fulltext/143193.pdf worth a read for detail.

[AussieTrooper]

Not sure this is a good idea. The human brain may struggle to process spatially in the same way as looking out the window and into a mirror.
It would have to be extensively tested and followed up in real life conditions. A few % drag isn't worth it if it increases accidents.
Unless you are a rural driver, drag is only a minor cause of fuel consumption.