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Old 10-03-2023, 08:16 AM   #3 (permalink)
Vekke
Mechanical engineer
 
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Join Date: Jan 2009
Location: Kitee (Finland)
Posts: 1,272

Siitin - '98 Seat Cordoba Vario
90 day: 58.56 mpg (US)

VW Lupo 3L --> 2L - '00 VolksWagen Lupo 3L
Diesel
90 day: 104.94 mpg (US)

A8 luxury fuel sipper - '97 Audi A8 1.2 TDI 6 speed manual
90 day: 64.64 mpg (US)

Audi A4B6 Avant Niistäjä - '02 Audi A4b6 1.9tdi 96kW 3L
90 day: 54.57 mpg (US)

Tourekki - '04 VW Touareg 2.5TDI R5 6 speed manual
90 day: 32.98 mpg (US)

A2 1.4TDI - '03 Audi A2 1.4 TDI
90 day: 45.68 mpg (US)

A2 1.4 LPG - '02 Audi A2 1.4 (75hp)
90 day: 24.67 mpg (US)
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It's not a easy puzzle. Some say 15% for wheel drag. That seems way too low.

Modern evs drag coefficient is under 0.25 so wheels impact is bigger than some time ago with fossil cars.

Weigth of them are generally also high so rolling plays bigger impact.

Then you add the fact most evs have very wide tires.

That 40% aero drag from wheels and tires I got by using 0.09 Cd increase to model y which is 0.23 car.

10% savings were reached easily without optimizing the tire deflectors, just with 195/60r18 tires, and the offset was also not optimal in first tests.

I have calculated 20% savings when optimizing deflectors for narrower tires.
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Last edited by Vekke; 10-03-2023 at 08:24 AM..
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