12-16-2017, 07:00 PM
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#1 (permalink)
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Master EcoModder
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How young/old were you when you learned that air flow effects efficiency
8th grade .
I took an elective called exploring Technologies 1 second semester number 2.
In 1 we built
1 a kinetic energy rubber band car.
We did full layout designs with abace meterial of 12" of 1/2 x 3/4" jard wood . More about practical application of ratios and Leverage
2 a CO2 rocket car .
one Maybe this one.
We receved a kit that consisted of a block of balsa wood 300x100x50mm with a chamber bored for a standard CO2 cartrage. 4wheels axels and an instruction book.
We were completing amongst each other as when finished they were drag raced 100m . We started on paper and desined a body shape in 2 plains. This got the wheels turning
What forces are going to be expected at over 100mph? Lift, drag, thrust , thrust vector, aero balince, and vortex sheading.
We got a good example of poor aero balince . One car had too much down force aft and lift in front ,it snaped in hafe . One had lift it tryed to fly like a side winder missle. .
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1st gen cummins 91.5 dodge d250 ,HX35W/12/6 QSV
ehxsost manafulld wrap, Aero Tonto
best tank: distance 649gps mi 24.04 mpg 27.011usg
Best mpg : 31.32mpg 100mi 3.193 USG 5/2/20
Former
'83 GMC S-15 Jimmy 2door 2wd O/D auto 3.73R&P
'79 Chevy K20 4X4 350ci 400hp msd custom th400 /np205. 7.5-new 14mpg modded befor modding was a thing
87' Hyundai Excel
83 ranger w/87 2.9 L FI2wd auto 18mpg on the floor
04 Mitsubishi Gallant 2.4L auto 26mpg
06 Subaru Forrester XT(WRX PACKAGE) MT AWD Turbocharged 18 plying dirty best of 26mpg@70mph
95Chevy Blazer 4x4 auto 14-18mpg
04 Chevy Blazer 4x4 auto 16-22mpg
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12-16-2017, 08:10 PM
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#2 (permalink)
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Master EcoModder
Join Date: Dec 2014
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My first aero design
This is aproxamitly what the car looked like..
2nd semesters was ET2
Were we built modle rockets and a bridge .Useing 1/8"x1/2" balsa wood and elmers wight glue. spanning18" gap . we bult bridges with a road deckof poster bordk thick paper) and the weight was supported by this deck, simulating a car loading. to a block of wood thorough a 1" square hole in the center . bridge held 110lbs for 2nd place 1st was 217lbs lowest was like 17lbs . we were aloud any supper or sub structure design with the supplyed wood and glue.
__________________
1st gen cummins 91.5 dodge d250 ,HX35W/12/6 QSV
ehxsost manafulld wrap, Aero Tonto
best tank: distance 649gps mi 24.04 mpg 27.011usg
Best mpg : 31.32mpg 100mi 3.193 USG 5/2/20
Former
'83 GMC S-15 Jimmy 2door 2wd O/D auto 3.73R&P
'79 Chevy K20 4X4 350ci 400hp msd custom th400 /np205. 7.5-new 14mpg modded befor modding was a thing
87' Hyundai Excel
83 ranger w/87 2.9 L FI2wd auto 18mpg on the floor
04 Mitsubishi Gallant 2.4L auto 26mpg
06 Subaru Forrester XT(WRX PACKAGE) MT AWD Turbocharged 18 plying dirty best of 26mpg@70mph
95Chevy Blazer 4x4 auto 14-18mpg
04 Chevy Blazer 4x4 auto 16-22mpg
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12-16-2017, 08:30 PM
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#3 (permalink)
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Rat Racer
Join Date: May 2011
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Not flow in the sense of controlling it to reach desired effects like downforce, but early on I got a practical lesson in the value of minimizing resistance.
4th grade, Pinewood Derby in Cub Scouts.
In third grade, they called my car "The Golden Potato." I rounded off the font and rear ends and painted it gold. Of all the cars in our pack, it was one of them. In fourth grade I just cut the thing into a low wedge, like a lower, wider version of the wedges people prop doors open with. Some melted fishing weights into recesses in the bottom to bring it up to max weight, and Fat Charlie's car with less frontal area than anyone else's beat everything the whole pack could throw at it. Somewhere in my dad's house is a polaroid of me in the front yard in my Cub Scout uniform holding a large trophy.
The next year everyone but the third graders (who hadn't been there to see my rig clean up) fielded low wedges, my execution wasn't the best and I got eliminated early. Sic transit gloria mundi.
Later in watching F1 I learned how they tried to improve average speed over a lap by adding or reducing downforce, but I haven't done any work myself in optimizing aero beyond drag reduction.
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Quote:
Originally Posted by sheepdog44
Transmission type Efficiency
Manual neutral engine off.100% @∞MPG <----- Fun Fact.
Manual 1:1 gear ratio .......98%
CVT belt ............................88%
Automatic .........................86%
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12-17-2017, 02:24 AM
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#4 (permalink)
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Master EcoModder
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There four of us in the back of a station wagon, of various ages. The radio antenna snagged a butterfly and folded it's wings neatly to either side.
We screamed and cried to stop and let the butterfly loose. Our father let us know in no uncertain terms that the stopping and starting of the mass of the vehicle and it's contents would involve more energy than 10 or 100 butterflies. And shut up.
The peak of my aerodynamic experience was a 1/10th scale R/C car. Someone else did the drivetrain and I did the paint and body. I left the front wheelwells as uncut clear plastic and cut the whole back out, basically a rectangle 90% of the frontal area.
On the back straight the downforce would suck dust out of the pavement and leave a trail hanging in the air.
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.Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster
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12-17-2017, 03:24 AM
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#5 (permalink)
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EcoModding flying lizard
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Probably around 14 years old, when I found this site. I don't think I really considered it before that.
I also used my aero knowledge to build a CO2 car that beat everyone in my class. It may have also helped that my car was probably half the weight of everyone else's cars. They put several coats of paint on their cars, I put one. I think I also used graphite lube for the axles. My car got up to speed and stayed there, theirs didn't go so fast, and lost just like that.
Ultimately, my car got defeated because it was too low, and the guide line hook dragged on the ground and busted off at the end of the track. So no #1 school car, but I still beat everyone in my class.
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-Kaze o tatakaimasen-
Best trip in V6: 52.0
Best tank in V6: 46.0
Best tank in Mazda: 49.9
Best tank in CBR: 61.3
Best tank in SV: 83.9
Quote:
Originally Posted by MetroMPG
You can lead a fashion-conscious horse to unusual-looking water...
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12-17-2017, 08:36 AM
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#6 (permalink)
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Master EcoModder
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It became relevant when I started cycling at 15. Wasn't concerned about it before that.
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The Following User Says Thank You to Stubby79 For This Useful Post:
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12-17-2017, 11:13 AM
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#7 (permalink)
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Not Doug
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Thursday?
As far as I know, I competed a few times in Pinewood Derby. I remember attempting to make my car look like a Ferrari, despite having completely different proportions. I won "Most Realistic," while the most popular car won "Because Batman." I do not have any idea who won or what was unique about their car. I am sure that I entered other times, but I only remember one race and possibly another one when there was an older kid that easily beat everyone. He had the maximum weight and I believe that, instead of trying to make his car look pretty or have an "aerodynamic" shape, he just made it as small as possible. He also ran my car down the track backward, but it was not any faster.
I also built a CO2 car, but it seemed like everyone focused on being as light as possible. I had some concept that if I made it shorter it would be lighter, but less stable.
I used to go on bike rides for fun, but when I was nineteen I learned about street slicks, and I thought everything else was about power and reducing mechanical friction.
When I was nineteen I talked to someone who complained about the "suction" behind a pickup. I asked if putting a wedge in the bed would help.
He did not think it would.
When I bought my first car, a friend had a 2007 Kia Sportage, and he kept upgrading it to make it better off-road. I always wanted to upgrade my car to be faster, despite not actually wanting to drive faster. I struggled to maintain the car, so I could never afford to upgrade anything.
I never thought about making it more aerodynamic.
So, I had plenty of opportunities, but do not believe that I understood the importance until I came here trying to figure out how to make my Forester more aerodynamic. I always wonder if, had I had a more efficient car, would I have ever learned of this site?
I like it here.
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12-17-2017, 11:54 AM
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#8 (permalink)
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Master EcoModder
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Early 20's, probably. At least, that's when it really sunk in. I remember having thoughts early in college like, "Wouldn't cars be more fuel efficient if they took all of that heavy bodywork off? Is it just for looks?"
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12-17-2017, 01:27 PM
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#9 (permalink)
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(:
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As a wee lad I liked to stick my arm out the window of the car and, by changing the angle of my hand, cause it to go up or down or even swing back when cupped like a 'chute. Ha Ha, never belted in back in the day.
By '83 I was deep into thinking about and sketching aero cars and motorcycles. I finally brought my work into the 3-D realm then:
I guess the first "real" aero work was a college research project/paper where I built and coast-down tested aero add-ons like skirts, air dams, grille blocks, and such. The results were inconclusive.
Concurrent with that, I got my Pilot's License and that has more than a little aero training.
Later on I researched, tested, and designed bodywork for off-road vehicles. There, aero wasn't so much about lift or drag as it was about operator comfort, cooling, and other concerns.
Last edited by Frank Lee; 12-17-2017 at 01:33 PM..
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12-17-2017, 02:19 PM
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#10 (permalink)
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Master EcoModder
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I suspect, truth be known, everyone starts with a hand out of a car window. That's the aerodynamics. The efficiency part comes in comparing the entire life cycle of a butterfly to gasoline exploding 20,000 times a minute.
I was drawing sports cars in high school but I can't lay a hand on an example at the moment. I was in college when Bruce Meyer created the Meyers Manx with buggy headlights and an upright windshield. I drew these:
I still like the idea of that lift-off top. Today, I'd make it the front half of a tapered bubble, so you could lift it off and store it on the back.
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.Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster
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