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Old 10-24-2016, 06:58 AM   #2261 (permalink)
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Quote:
Originally Posted by Magajgfha View Post
If laminar flow has higher drag than turbulent one...............

Aerodynamic != low drag.
Yes, a car that has high downforce and high drag, but good L/D is aerodynamic.
I'm not convinced they used the phrase laminar flow correctly there, I think they just meant to say it's a low drag wing up front , unlike the rear one I might add.

I think Frank Lee is trying to apply some well accepted rules, but with improper results/conclusions.

The car body (like a wing) can be designed to be high lift, or high down-force, and the drag might even come out to near the same in either model.

The drag is what we might want to be concerned about, and as long as you are going teardrop instead of wedge your are going to be ahead of the game.

Remember this car's body is not an airplane wing, it is more like the fuselage.

Being a fuselage, the rules on tapering, body length, frontal area and overall drag are the dominating factors.

If your three basic choices for car body are 1.) neutral, 2.) high lift, 3.) high down-force then for a high performance car I think they choose correctly.

These three choices are relative theoretical extremes. The actual applied results will be something in between in real life.

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Old 10-24-2016, 08:28 AM   #2262 (permalink)
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I don't see my improper conclusions.

Downforce is a force. It takes energy to make it. Similar body shape w/o downforce would have less drag.
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Old 10-24-2016, 10:15 AM   #2263 (permalink)
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Quote:
Originally Posted by Frank Lee View Post
I don't see my improper conclusions.

Downforce is a force. It takes energy to make it. Similar body shape w/o downforce would have less drag.
I don't see problems with your statements, just your conclusions as applied to a real world situation, and not some theoretical one.

This real world situation has a call for down-force at high speed for safety, a theoretical situation does not have such a requirement.

So here are your two real life choices.

1. A neutral lift aerodynamic body with sizable wings for down-force.

2. A negative lift aerodynamic body with much smaller wings.

The point is, once you have committed to having some down-force for safety at high speed you need to make a design decision, and not some philosophical statement.

Frank-Lee, if your point is that there would be less drag with no down-force, then yes you win that argument.

You might die in such a vehicle quite easily, and that would make me sad.

The trend to add large wings (Ferrari F-40) then remove as much wing as possible (the Enzo) has been lead by cars with high top speed and high performance.

The Aston Martin AM-RB 001 is simply expressing a trend which was started in racing decades ago, that is to rely on the body, not wings for down-force. Some of this innovation was force by rules limiting wing size, other changes made in the name of efficiency.

If anyone wants to take this into a discussion about lifting bodies, and blended wing aircraft design verses conventional winged aircraft they could. However I say let's stay focused.

https://www.pinterest.com/pin/475200198154450006/


Interesting seating position, but that's no sidecar.

This thread, and post #43 is a good follow up to our discussion:
http://forums.pelicanparts.com/porsc...ea-tray-3.html
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Old 10-24-2016, 11:09 PM   #2264 (permalink)
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I now see where I did err. The max downforce car does belong in the aerodynamic car thread because the title of the thread isn't "Low drag aerodynamic cars". I instinctively interpreted it to mean low drag but really aerodynamics can be the means to most any end and there are legit ends other than low drag, one of them being downforce.
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Old 10-25-2016, 07:53 AM   #2265 (permalink)
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Quote:
Originally Posted by Frank Lee View Post
......... aerodynamics can be the means to most any end and there are legit ends other than low drag, one of them being downforce.
And you were correct in stating that down-force takes energy to generate among other things.

We need to keep in mind that when the forward motion is powered by the wheels (excluding jet/rocket cars here) there are conditions such as in turns where added down-force translates into higher speeds (because of traction).

This picture below is curious in that the wings provide only about half or the down-force.

https://www.quora.com/How-much-downw...n-acceleration

Quote:
Let me repeat it so it's clear: airfoils add drag, reducing your top speed and top-end acceleration. But at high speeds, they push the car down and add traction so you can turn faster. This is a trade-off.
A classic aerodynamic car below.................a repeat for sure.

The Top 20 Dumbest Cars Of All Time


Look out pedestrians.................
http://stormbear.com/post/5111257185...ome-made-motor



http://www.businesspundit.com/chines...nely-weird/10/


http://www.rodsnsods.co.uk/forum/his...stom-car-26530
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Rear Spoiler Pick Up Truck
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Old 10-25-2016, 09:09 AM   #2266 (permalink)
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kach22i

That last car you posted is cool.

I found more pictures of it here.


What Car Is Hidden Under This Custom Vegas Cruiser?




>
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Old 10-25-2016, 09:32 AM   #2267 (permalink)
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Quote:
Originally Posted by redneck View Post
.I found more pictures of it here.


What Car Is Hidden Under This Custom Vegas Cruiser?
I did not realize this car used buttresses.

Not the most aerodynamic solution but may influence my future pickup truck experiments.



Like this?

http://jalopnik.com/5204309/jaguar-x...e-toting-needs



Just needs an adjustable roof wing now.
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1989 Scat II HP Hovercraft

Chin Spoiler:
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Rear Spoiler Pick Up Truck
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Old 10-25-2016, 01:56 PM   #2268 (permalink)
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That might be a necessary compromise for a pickup, but as with the Dodge Daytonas, it [literally?] sucks aerodynamically. From Permalink #2184:



The third taillight is a nice touch, but it needs to be 2-3" lower to line up with the others. Maybe the license plate could be offset to one side.
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Old 10-26-2016, 12:12 AM   #2269 (permalink)
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The fan car is awesome! I know where there's a small airplane that's broken in half from flood damage, but still runs....... Nah not my kind of project.
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Old 10-26-2016, 08:17 AM   #2270 (permalink)
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Quote:
Originally Posted by ChopStix View Post
@kach22i

The fan car is awesome! I know where there's a small airplane that's broken in half from flood damage, but still runs....... Nah not my kind of project.
I'm pretty sure that we have posted several versions of this concept in this thread before. However what makes these latest photos special (for me) is it is in actual operation on a road.

It just came to life in other words.


Better get out of the way.

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1977 Porsche 911s Targa
1998 Chevy S-10 Pick-Up truck
1989 Scat II HP Hovercraft

Chin Spoiler:
http://forums.pelicanparts.com/off-t...effective.html

Rear Spoiler Pick Up Truck
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Roof Wing
http://ecomodder.com/forum/showthrea...1-a-19525.html
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