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UGMENTALCASE  
#21 Posted : Thursday, May 10, 2018 4:02:21 PM(UTC)
UGMENTALCASE

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Here is just the surfaces built up together
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UGMENTALCASE  
#22 Posted : Thursday, May 10, 2018 4:15:59 PM(UTC)
UGMENTALCASE

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Solids included in this file for you. You'll need to thicken the surface before adding together.
Hope this helps

Cheers
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Art Smith  
#23 Posted : Thursday, May 10, 2018 4:18:19 PM(UTC)
Art Smith

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Originally Posted by: UGMENTALCASE Go to Quoted Post
Ha ha, how?! Well It doesn't like the squished bottom and expanded top when you use some of the surface options.
So I used the option where you pick M and N curves. But I found the results changed when you selected either the guide curves first or the other curves first. So in this case I selected the guide curve type, and then the 7 or 8 profile curves.

I'd say you can adjust them to solid at the end yes. Can't see any reason why not. Repeat my steps to build the other half of that section. Then another surface to go from the circle shape to the rectangular type shape, join/add them all togetber, then thicken up maybe?

I'll build the other half in the morning, then run in he other surface and test it out. How thick do you need it?



thanks! 0.060"

to your point, one of the things the lofting routine probably doesn't like is the radius changing on both the outside and inside surfaces......... unfortunately no way to avoid it if the area is to change smoothly from inlet to outlet; there isn't physical space to increase the width!

Art
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Art Smith  
#24 Posted : Thursday, May 10, 2018 7:36:49 PM(UTC)
Art Smith

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to rockyroad_us's point, most of the problem was in my original file! after completely redrawing the lofting stations and guide curves, the vast majority (not all) of the rippling problem is gone. see the first attached collage showing the results with NO guide curves and the four baseline guide curves. huge improvement with only a trace of unwanted curvature remaining on the short side radius surface!! with most of the problem solved, I decided to explore the impact of additional guide curves in and near the short side radius surface (ie: the two blue guide curves in the surface at the end of corner radius and the two orange curves at the end of the corner radius in the side wall). using the baseline guide curves AND the two additional blue guide curves removed most (again not all) of the residual curvature in the short side radius surface. see the second attached collage. there was no observable improvement using the baseline guide curves, two blue curves, and the two orange guide curves! once the rate of change of area is dialed in for the lofted section between the rectangular station with radiused corners to the circular entrance, I'll likely try two additional guide curves in the short side radius surface half way between the blue guides and the baseline center line curve at the bottom. it would be interesting to know with certainty if the order of input of the guide curves has any influence on the creation of surface.

an example of the use of Tim's new AeroPack area/cg curve (1370) is shown in attachment 3. one of the spline guides was used to seed the tool and it correctly produced the CG/centroid curve of the duct/runner in 3D. in the example shown, it clearly illustrates that the lofting tool needs better guidance from the operator to get the area rate correct at the inlet!!

Art
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Edited by user Thursday, May 10, 2018 10:25:29 PM(UTC)  | Reason: Not specified

Art Smith attached the following image(s):
ripple answer 1 of 3.jpg (49kb) downloaded 1 time(s).
ripple answer 2 of 3.jpg (52kb) downloaded 1 time(s).
ripple answer 3 of 3 revA.jpg (49kb) downloaded 0 time(s).

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