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Mix an electrically conductive material into the paint of a car and then run an electric charge through it to heat the inpacting air which will reduce aerodynamic drag.
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Air doesn't conduct heat very well, so to heat up enough of the boundary layer enough to reduce drag at high speeds is going to require a lot of power. The power lost to the car's alternator to do this is going to more than equal the aerodynamic savings. |
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Maybe I'd have given you a bun if it were to change the car's colour, drag's just a drag. |
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Maybe you could use it to put flames on the fenders... |
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Perhaps waste engine heat could be aerodynamically directed over the vehicle's surface. It'll kill the A/C system, though, and be pretty rough on the body plastics. |
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Is the assumption here that a hotter car goes faster? I mean I think I understand the principal, hotter air is less dense and therefore creates less drag. But I fail to see how heating up the car itself is going to make much difference. Sounds kinda like vaccuming the dust out of the seats to lighten the cars load ot increase it's speed. |
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....and I was hoping for something that would change color based on the body's electromagnetic fields..... |
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I thought this would be body paint that changed according to your temperature, like a mood ring. And had something to do with electricity. |
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Again a question of the energy balance. How hot would it have to get? If you want the body temperature to rise by a few tens of degrees, you're certain to need more energy than you eventually save. Waste engine heat would work, obviously only if the car was designed to take advantage of it. However, air viscosity and density don't fall particularly rapidly with temperature, so the effect would likely be fairly small. |
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We don't need no stinking Electro-thermal body paint 'round here. We use the sun and flat black paint. I wonder if we get better fuel economy here in the desert? :) |
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How about using electrostatic charge to decrease drag? The surface of the car could have an array of electrodes each capable of forming a charge of thousands of volts. |
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