Quote:
Originally Posted by examorph
Me and a group of people are making a small car which is powered by an electric motor for a race, I am having a hard time deciding on a design for the bodywork, after researching I thought the best design would be a tear drop since many say it has the lowest drag coefficient of any natural shape, what are your thoughts on this?
Some extra information: The cars maximum speed will probably not go over 30mph, the front and rear wheels have to be in-line.
An additional question, we are using bike tyres for the wheels on the vehicle, is it worth covering these up or at such low speeds will the drag not be noticeable?
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The lowest drag forms are 'streamlined bodies of revolution.'Or 'teardrops.'
'Half-bodies',derived from streamlined bodies of revolution produce drag coefficients on the order of Cd 0.08 in ground proximity.When wheels are added the drag goes up to Cd 0.12-.13.With the narrow bicycle tires you might see on the order of Cd 0.10 if wheel fairings were employed.
If your team is attempting to stretch the range of the battery pack the 'teardrop' form could help with that.
In the Sunrayce '95,a 'torpedo'-shaped 'TNE-3',3-wheeler from Northern Essex Community College was achieving 150 mile range at 55-mph (US statute miles) on a single charge,equivalent to over 350 mpg.
This car was about 3.84 times as long as it's body diameter with Cd 0.10.It would be worth checking out.