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Old 10-28-2020, 01:02 PM   #178 (permalink)
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I did some back-of-the-envelope calculations with the 2018, University of Michigan, NOVUM, solar racer, Cd 0.10, Af approx. 7.788-sq-ft, curb weight 420-pounds, Length- 196.0-inches, width- 38-inches, and height- 35-inches. 4.8-hp. top speed- 85-mph.
I 'inflated' the car, growing to the height of a common, contemporary sedan, height= 55.5-inches, width= 60.25-inches, and length= 310-inches ( wow!)
Using a rough cubic displacement relationship, the weight would come in around 1625-pounds, with 19.145-hp, a 19.943-kWh lithium-ion pack, and 90mm Schwalbe 'Cruiser' tires.
I allowed an inflatable, 45.8-inch tail, to allow for garage parking. Top speed would be held to 85-mph. Allowance for 2.775-inch ground clearance ( air suspension ).
It would be 2-place. 1,975- pounds with two aboard.
Cd 0.10, Af 19.583-sq-ft, CdA 1.9583 sq-ft.
At 65-mph, the road load is 7.887=horsepower, 90.519 W/mile. 3.389-hours drive time to battery exhaustion, 220-mile range, at 371.76 mpg-e.
A crude metric for ICE would be, figure 1/3rd the efficiency of a BEV, so with a gasoline powerplant, you might expect to see 124-mpg @ 65-mph constant velocity, with two side mirrors.
For comparison, Dr.Paul MacCready of AeroVironment, estimated the 1987 GM Sunraycer at 400-mpg, if powered by an ICE powertrain.
A streamlined, 2018 LEAF SV would be looking at 198 mpg-e HWY, and 235-miles range, vs 148-miles and 125-mpg-e.
100-mpg is there for the doing. You just really got to want it. With BEV's it's no challenge at all.
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