EcoModder Forum Making a more efficient, aerodynamic soapbox gravity race car

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Quote:
 ...what do you think?
Not dangerous? I was going by the pic at Permalink 252, and I was fishing for information on the white wedges forward of the wheels.

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curve

Quote:
 Originally Posted by freebeard That's the diagram I don't get. I presume l(c) is overall length? What is the relationship between the angle and height graphs? The two curves don't track each other. Maybe if there was a curve for l(d)/l(c)=1 I could get the sense of it.
They only offer us two different lengths,as a percentage of overall body length and without a 3rd example,we've got nothing to create a curve from,nor interpolate/extrapolate.
With the two versions shown they only structure the drag and lift as a function of up-sweep angle.
For us,we can only inspect what we've got and see which variety would best suit us,then go from there,hoping for the best.
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 The Following User Says Thank You to aerohead For This Useful Post: Joggernot (07-27-2016)
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get it

Quote:
 Originally Posted by orengomotors i don't get it too
Here you can see that a diffuser isn't even possible

With the engine in front,the diffuser IS possible,and it can begin very 'early' on the underbody,allowing the lowest drag version

Here,whatever is under the pan,it won't allow the diffuser to begin as early

With the race car,there will be a point where the hard points clearance will just allow the diffuser to begin.Then it's a matter of what you want,rear downforce,or low drag.
Some current supercars (Bugatti and Ferrari),have active flaps which 'close' the diffuser for straightaways,and 'open' them for corners.
Here,you can see the 'shiny' diffuser flaps of the Ferrari LaFerrari
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 The Following User Says Thank You to aerohead For This Useful Post: Xist (07-27-2016)
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Quote:
 Here you can see that a diffuser isn't even [always] possible
AKA the Beetle problem.

 The Following 2 Users Say Thank You to freebeard For This Useful Post: aerohead (07-29-2016), ChopStix (07-28-2016)
 The Following User Says Thank You to noultimatum For This Useful Post: Fastskiguy (08-14-2016)
 08-09-2016, 03:03 PM #266 (permalink) Master EcoModder     Join Date: Aug 2012 Location: northwest of normal Posts: 19,245 Thanks: 5,392 Thanked 6,350 Times in 5,092 Posts Welcome(?) to Ecomodder. Is that Dallas, Oregon? since 2011? You can be logged in and it will time out behind you back. Always hit Select All/Copy before you Post or Go Advanced. Sometimes reloading the page doesn't help and you have to leave it and come back and Paste again. A big advocate here of the [hypothetical] hypermiling technique 'Drive Without Turning' would be slowmover. When I'm driving the Coast Range, I try to turn only in the middle of the short straights and hold a steady curve that touches the apex. A quick body roll while the car is not turning and then steady as she goes the rest of the time.
 08-09-2016, 04:01 PM #267 (permalink) EcoModding Lurker   Join Date: Mar 2011 Location: Dallas, TX Posts: 6 Sippy - '96 Mazda Protege LX 90 day: 40.88 mpg (US) Jack - '04 Lexus GS300 Thanks: 3 Thanked 2 Times in 2 Posts Haha. Edited... TX . Thanks for the comment. And yeah. Lesson learned about copying the text before submitting.
 The Following User Says Thank You to noultimatum For This Useful Post: freebeard (08-10-2016)

 Tags aero, low drag, soapbox, streamlined