Ford F150 - 25% drag reduction

[aerohead]

Originally Posted by wouterremmerie

Hi Aerohead,

no, we use a finite volume method:
this has been the default method for decades, although I do believe LBM could be (one of) the winning methods for the future.

Regarding drag values:
without discrediting the manufacurers, the claimed values are usually fairly optimistic (as they sometimes play with ride heights, rims, aircon settings, etc during testing).

We performed an independent validation on a Tesla Model Y together with one of our partners - our Cd value was less than 6% off compared to the measured value. And qualitative data (the flow structure behind the car) also showed good correlation:
airshaper.com/blog/tesla-model-y-aerodynamic-benchmarking

I would agree drag hasn't increased by 14%, so it's likely more a matter of comparing the right data here. Data coming from different sources and/or different measuring techniques (tunnel vs simulation) can blur the whole story.

Thanks!
My single brain cell activated, and it struck me that Ford Motor Company would be required to publish a 'crosswind-averaged' drag coefficient for EPA ( maybe ISO ) certification.
Some of the discrepancy between data may be wrapped up this manner in the 'way' they're required to report.
The qualitative 'trends' DO appear to be spot-on!
Thanks again!

[wouterremmerie]

Originally Posted by aerohead

Thanks!
My single brain cell activated, and it struck me that Ford Motor Company would be required to publish a 'crosswind-averaged' drag coefficient for EPA ( maybe ISO ) certification.
Some of the discrepancy between data may be wrapped up this manner in the 'way' they're required to report.
The qualitative 'trends' DO appear to be spot-on!
Thanks again!

That makes sense on the EPA cross wind!
Also, we ran new sims on the Ford F150 Lightning, and drag has gone down by a lot (can't tell by how much, but maybe we'll launch a post soon if we get the approval).

[aerohead]

Originally Posted by wouterremmerie

That makes sense on the EPA cross wind!
Also, we ran new sims on the Ford F150 Lightning, and drag has gone down by a lot (can't tell by how much, but maybe we'll launch a post soon if we get the approval).

Ford admitted that they were playing it safe on design, not wanting to put off ( scare off ) loyal customers by making the F-150 look like a 'science experiment'.
Since the thermal efficiency of the motor/inverter is around 95%, a reduced cooling system porosity would allow for ample cooling at less internal drag, and 'never show.'
Will be very interesting to see the new numbers when you get the green light.
PS
Member 'bondo' (Brett Herndon ) produced a wind tunnel-tested bedcover and tailgate boat-tail for the 2012 F-150. Together, they cut Cd 0.098 off the truck, achieving close to CYBERTRUCK's advertised Cd 0.30.

[Thielsenmadam]

The 14% drag reduction from the bed cover. Does anyone know if that is a design anyone is selling yet?

[freebeard]

Your search term is "aerocap".

[aerohead]

Originally Posted by Thielsenmadam

The 14% drag reduction from the bed cover. Does anyone know if that is a design anyone is selling yet?

That ship sailed long ago, at least in the USA.
* Pop-a-Top marketed an aeroshell in the late-80s. I saw one in Dallas, Texas, once.
* EcoModder.com member Brett Herndon ( aka: bondo ), who's a master clay modeler, designed, wind tunnel tested, patented, and manufactured an exquisite aeroshell, plus boat-tail back around 2012.
* The marketplace punished him for all he did.
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There are many pages dealing with aerohells/ aerocaps, etc., in the back pages somewhere here at Aerodynamics Forum.