Kammback doesn't work on my sedan

[d0sitmatr]

heh
not really, unless its corroborating with my theory of using the wingtail for downforce

[SlideWRX]

Originally Posted by AeroModder

The Bonneville flat spoilers also have vertical plates on the sides.

I'll bet that helps interrupt vortex creation. On wings (planes or race cars), side plates effectively extend the wingspan, but I think they are also used to minimize vortex's. In this case, they probably also help the air flowing around the side pull in and re-attach, kinda like the air flowing over the roof going down to the trunk.

I wonder how much benefit one can get from a stepped down boat tail versus a regular boat tail. Better visibility out the rear window, methinks.

Tom

[euromodder]

Originally Posted by SlideWRX

On wings (planes or race cars), side plates effectively extend the wingspan

On aircraft, they are used to eliminate spanwise flow which reduces wing efficiency.
Basically, they keep the air where the designer/engineer wants it - in this case on the most aerodynamically efficient path on the vehicle.

Check out the Ford Bonneville car : it also has strakes on the roof and in front of the extended tailplate on the trunk, while the rear window sits slightly deeper, also creating a fence on the sides.

I wonder how much benefit one can get from a stepped down boat tail versus a regular boat tail. Better visibility out the rear window, methinks.

If the angle of the rear window isn't too large and abrupt, just boat-tailing the trunk area will most likely do the trick.

[ECONORAM]

After seeing what Piwoslaw, Wyatt, Darin and others have done, I am wondering if I can create something similar for my Dodge RAM QC. Since I swapped the tonneau cover for a topper, I have noticed FE has dropped. I figure a kammback or boattail (boy would THAT be long....) would help drop the drag. Could I take the same basic picture here and apply it to my truck, or do I need to go to that extreme?

Sorry about the hi-jack. Dave

Originally Posted by cfg83

3dplane -

*IF* my center-of-camber selection is correct, then I would make the claim that the angle is too steep and the airflow is not staying attached :



I agree with Weather Spotter that a longer kamm-back would be better, but I also think that if you get the angles right, it should still be a net benefit. I think that aerohead had a table of "diminishing returns" of a boat-tail. Obviously a full boat-tail would be best, but pragmatic concerns make it necessary for ecomodders to figure out how far they want to go.

But I'll let the real aero-experts chime in.

CarloSW2

[cfg83]

ECONORAM -

I don't have the answer to your question, but the slope might look something like this (if I have the correct image) :



CarloSW2

[Weather Spotter]

Originally Posted by cfg83

ECONORAM -

I don't have the answer to your question, but the slope might look something like this (if I have the correct image) :



CarloSW2

That looks about right to me. I have seen people just go from cab roof to top of tail gate with good results but following the template is better.

[BamZipPow]

Originally Posted by cfg83

ECONORAM -

I don't have the answer to your question, but the slope might look something like this (if I have the correct image) :



CarloSW2

You could do this...
http://ecomodder.com/forum/showthrea...dea-15137.html