The speed that aerodynamics are important

[aerohead]

I added a couple images back at #18 (permalink ) which may assist in conceptualizing aerodynamics and it's relationship with velocity.

[j-c-c]

Originally Posted by aerohead

https://ecomodder.com/forum/member-a...sugar-cube.jpghttps://ecomodder.com/forum/member-a...oads-up-18.jpghere are some numbers I pencil-whipped for the Chevy BOLT I'll be getting in September.
I used Cd 0.31, Af 25.7-sq-ft, 0.00238 slugs air density, and 3,880-lb test weight.
Aerodynamic horsepower requirements are presented in 5-mph increments, from zero-to 100-mph:
0-mph = 0
5-mph = 0.0067
10-mph = 0.054
15-mph = 0.183
20-mph = 0.435
25-mph = 0.8497
30-mph = 1.4683
35-mph = 2.3316
40-mph = 3.4805
45-mph = 4.9557
50-mph = 6.7979
55-mph = 9.048
60-mph = 11.7468
65-mph = 14.9351
70-mph = 18.6535
75-mph = 22.943
80-mph = 27.8444
85-mph = 33.3983
90-mph = 39.6456
95-mph = 46.6371
100-mph = 54.3836
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Over the same speed spread, power absorbed from rolling-resistance increased linearly, from zero, to 8.9873-hp ( using a Cfrr of 0.008686291 ( probably 'high' )) [ Bridgestone Ecopia is around 0.005 ].
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If everyone constructs one of these tables from 'day one', 'curves' can be constructed from the data-plots for aero and R-R, plus adjustment for mechanical efficiency, and presuming a constant BSFC, or BSFC-e for BEVs, one can predict, at any chosen velocity, what mpg, or 'range' their vehicle will return.
I photo-reduced my table and chart, in full color, at a local UPS/ Post Office store, and laminated it, creating a 'card' which fits in my fanny pack or clipboard, for 'thinking' and trip-planning.
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PS:
Because I ran these numbers, I know from the science that with aero mods, the BOLT has a shot at over 300-miles range on it's 'recall' 63-kWh pack, before I've bought it.
'Knowledge is Power'
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Extra PS:
here's a very old, pre-radial tire power graph for rolling-resistance vs velocity. It's 'nothing' compared to aerodynamics
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extra extra PS
Here's the aerodynamic challenge. The hen egg and sugar cube have identical drag ( Thanks to Chrysler Corporation for the data ).
The hen egg is 21-X larger than the sugar cube, yet 'same' drag.

All to mean, if nothing else, Time is money, or in this case, fuel.
What was the total calory comparison between the egg and the cube?

[mort]

sugar cube: 15 cal
egg: 70 cal

[Phase]

but which one spikes insulin more?

[sgtlethargic]

Originally Posted by Phase

but which one spikes insulin more?

Since blood sugar spikes are often coupled with blood sugar dips ...