Quote:
Originally Posted by JacobLeSann
I found a blueprint of the car, and printed it out. I have poor computer skills so its tiny. The EBLA from the trunks rear edge to where it contacts the end of the roof is 17 degrees. Its very weird to measure given the roof curvature.
So it looks like thats another piece of the puzzle.
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From what I understand, these are the three problems with the top rear of the car:
-EBLA is a bit too steep. Should be 6 degrees lower as a rule of thumb.
-Separation bubble ahead of trunk lid, Center of rear glass. This disrupts flow and could easily be causing lift.
-Boundary layer seems thick. When using a long tuft to estimate EBLA, it likes to float 1-3 above the rear of the car. This seems to be reflected in the rain.
As I plan to keep this car another 1-2 years, I want to build a proper fiberglass bodykit designed to lower drag. For this section of the car, I dont want to modify anything but the trunk lid (I have an OEM spare). I want to make it aesthetically pleasing, at least to my eyes. Most importantly, I want to have functional rear glass visibility.
Given those parameters, I think Ive done pretty much everything so far. Maybe the next step is seeing what happens if I energize the boundary layer
? Hmm.. |
That's likely a good call.
The three cars I have , with Bonneville spoilers, which set land speed records, happened to place the spoiler's tearing edge right at the AST-III contour interface.
* The Ford Fusion 999 ended up with an EBLA of 13.0-degrees
* The GM Chevy Cobalt ECOTEC had EBLA = 10.0-degrees.
* I do not have the HOTROD Magazine, 'Project Red Hat', Chevy Camaro with me.
* Just for giggles, if you can figure out how to place the HONDA under the AST-III, as directed, the scale measurement it depicts could be compared to what you've fabricated so far.
As always, we're discussing 'shape drag', so, proper aero solutions 'ARE' going to have a particular 'look' to them, when seen in 'true length' as with your blueprint.
One out of one atmospheres agrees!
