Quote:
Originally Posted by JulianEdgar
Um, to you it might need psychic powers. To everyone else it's pretty obvious that the change in drag wasn't 6.300000%.
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Speculation?
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Here's an example of a reverse-engineering challenge involving Tesla's Model S
* Julian Edgar reports that the Model S has a 8% cooling-drag system.
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The Tesla Model S has been reported with:
Cd 0.26
Cd 0.247
Cd 0.24
Cd 0.225
Cd 0.208
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SAE 2012-01-0178 provides us with a frontal area of 2.4-meters-squared ( 25.8333 sq-ft )
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This gives us a range for the Model S drag factor, from CdA 6.7166 sq-ft ( 0.6239 meters-squared ), to, 5.3733 sq-ft ( 0.49919 meters-square )
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This range offers a spectrum of at least five-different cooling-system drags.
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Since Julian Edgar has not provided any specificity as to what ' 8% ' actually means, ' 8%' remains an unknown quantity to any of the 136,000 EcoModder.com members who might wish to 'engineer' cooling systems.
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I'm often uncertain what underlies the motivation for some of Julian Edgar's posts. Certainly he must understand that members actually have a desire to 'engineer.'
And since the 'signal-to-noise ratio' of some mods complicates the ability to even discern an actual 'change' in drag, the need of highest specificity cannot be overemphasized.