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Old 04-07-2021, 07:12 PM   #90 (permalink)
JulianEdgar
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Quote:
Originally Posted by aerohead View Post
* You know that aerodynamic drag power requirements vary with the cube of the velocity.
* You must also know that if you're cooling a motor or batteries, that the aerodynamic portion of that cooling load will also vary as the cube of the velocity.
* 155- cubed, divided by 77.5-cubed will give you the difference in radiator size for the aerodynamic power-related cooling load for the Tesla Model S at theses two speeds. Some BEVs won't even go 77.5-mph! This is part of the 'context' which must be part of the discussion, or else it borders on complete intellectual dishonesty.
* The percentages you have for both Tesla and Porsche had better have this kind of information or it will be completely useless!
* God lives in the details.
None of that is relevant when we are talking about the drag coefficient penalty of cooling systems!

Like, it's why we use coefficients not absolute values.

If you think we need to be measuring speed, I guess that's one reason you're confused regarding the idea of cooling system drag as a percentage of the total drag coefficient.
 
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