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Old 05-15-2020, 10:40 AM   #36 (permalink)
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Have you ever measured pressure....?

I am university trained in both aerodynamic and hydrodynamic measurement.My senior project (thesis) involved the aerodynamic streamlining of my VW Transporter,which yielded an increase in highway fuel economy,from 27-mpg,to 35-mpg.For nearly 6-years,I earned my daily bread making these measurements.I orchestrated the wind tunnel testing of the Cd 0.11 Becker-Lyon,BMW,LSR motorcycle streamliner.I hold two USFRA speed records.Since 1986,I've probably been part of only a rarified community of motorists incorporating a relative-wind-seeking,slewing pitot-tube/airspeed indicator.
Since my projects mimic vehicles which have already been analyzed by simultaneous recordings of 42-pressure tap/manometer readings,drilling my car full of holes,and bankrupting myself purchasing hardware would be folly.I've been happy enough to spend thousands of $ on 3rd-party testing.
In 1951, Sighard Hoerner reported that the average passenger car had a frontal-area-based coefficient of lift of 0.40.At 50-mph,this translated to 60-pounds lift,on a car of 4,500-pounds.
The 1935 Jaray-Adler Sportwagen was measured at Cl= 0.20,which would generate 30-pounds lift under the same conditions.
Spirit of Ecomodder indicated a Cl= 0.00591.At 135-mph she generated 8-pounds of downforce.For a 4,220-pound vehicle this is essentially a 'zero-lift' vehicle. Modelled in part,after the FKFS K-cars,which FKFS reported as 'neutral',as far as lift is concerned.
There's a reason Hucho wasn't concerned with passenger car lift,as of 1987.Can you imagine why? And can you tell the audience what has changed about Earth's atmosphere,or physics since then,that we should obsess over it now?
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