Aerodynamic Streamlining Template: Part-C

[SvdM]

Hi, I hope this helps some more:

Bottom, Top and Side
Volkswagen XL1 picture # 44 of 46, Technical image, MY 2014, 1600x1200

Airflow over vehicle
Volkswagen XL1 picture # 29 of 46, Side, MY 2014, 1600x1200

[sgtlethargic]

Here's a quick and dirty comparison of the old template and the basis for the new template (blue). The fronts are aligned better than it looks. I made the heights similar to scale one to the other.

[sgtlethargic]

Aligning the lengths, I see no real difference in the two templates.

[kach22i]

Originally Posted by aerohead

*I've been working with a 'modified' 'Template' since early year.

It works nicely on my latest sketches, but I still have a way to go, no matter how you slice it.

I'll be using it as my standard from now on, thanks to all who have contributed to it.

Industrial Design - Transportation Photos by kach22i | Photobucket



Did I use the top view (mirror image below) correctly?
Industrial Design - Transportation Photos by kach22i | Photobucket


Here is the canopy from the top isolated.

[3-Wheeler]

Originally Posted by sgtlethargic

Here's a quick and dirty comparison of the old template and the basis for the new template (blue). The fronts are aligned better than it looks. I made the heights similar to scale one to the other.

Hi,

Your new template would seem to have a length/width ratio less than the minimum of 2.5:1 set by AeroHead.

Any thoughts on how you arrived at this length?

Jim.

[kach22i]

Originally Posted by 3-Wheeler

Hi,

Your new template would seem to have a length/width ratio less than the minimum of 2.5:1 set by AeroHead.

Any thoughts on how you arrived at this length?

Jim.

Does it really?

I did not check it myself.

I'd like to know how to align it, as there are several gaps making it hard to locate the high spot.

[sgtlethargic]

Originally Posted by 3-Wheeler

Hi,

Your new template would seem to have a length/width ratio less than the minimum of 2.5:1 set by AeroHead.

Any thoughts on how you arrived at this length?

Jim.

Hey Jim,
There is no width ("d" in 2.5d on "Aerodynamic Streamlining Template") in my sketch.

The idea was to overlay the new and old one for comparison- to see if there's much difference. Now that I think about it again, the first sketch seems correct because I aligned the heights as one would with the AST to scale it to a vehicle.

I will wait to see what AeroHead says, but I figured that comparison was a first step that could be done in an attempt to help.

Thanks,
Kurt

[aerohead]

Originally Posted by sgtlethargic

Hey Jim,
There is no width ("d" in 2.5d on "Aerodynamic Streamlining Template") in my sketch.

The idea was to overlay the new and old one for comparison- to see if there's much difference. Now that I think about it again, the first sketch seems correct because I aligned the heights as one would with the AST to scale it to a vehicle.

I will wait to see what AeroHead says, but I figured that comparison was a first step that could be done in an attempt to help.

Thanks,
Kurt

Thanks Kurt,I appreciate your jumping in.
I went back to the original 'Template' format,incorporating the full,2.5:1 L/D body of revolution in which the mirror-image 'Diameters' (2 X H = D) are matched,as well as the position of maximum body cross-section (Max. body camber point ).
I've ignored the 'noses' per se,as they are always discounted in Fluid Mechanics,and rather place the greater emphasis on the aft-body portion.
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When I compare the old with the new,I get a very close agreement in countours,except in the initial 20% or so of the contour,where the 'new' form is a bit 'faster.'
The 'rooflines' of the two 'Templates' eventually rejoin essentially and continue on maintaining a maximum 22-degree down-slope.
I'll continue my drawings and post Saturday.
My hope is to maintain the fidelity of D&F's original curvature,without introducing any 'bumps.'
Now having worked under higher magnification,the profiles are different enough that they don't combine until within the region of ground clearance,which is cut away.The images are posted now.The top image has hash marks designating the profile of the 1st-gen profile laid on top of the new 2nd-gen.It's much as you depicted it to be.

[sgtlethargic]

Originally Posted by 3-Wheeler

Hi,

Your new template would seem to have a length/width ratio less than the minimum of 2.5:1 set by AeroHead.

Any thoughts on how you arrived at this length?

Jim.

On third thought, I forgot about H = d/2, so I was wrong in saying there is no d in my sketch.

The template proportions should have stayed the same if/when I scaled the size.

[sgtlethargic]

Aerohead,
Will you please take a few minutes and explain the dashed lines, especially the one I marked? I think I understand the other dashed lines to represent the top (plan) view.