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Projected Area in SW

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malis

Mechanical
Nov 29, 2005
31
Is it possible to get the projected area of an assembly on say a plane. I'm doing a project that needs to include a force from the wind and I would like to find the total area in which it acts apon and I would also like to find the centroid if possible. Any Ideas on how to get this information?

Thanks

 
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Hopefully one of the gurus here can help you out. If not, here's a brute-force way to do it (which is not at all clean).

1. Create a model view normal to the wind vector.
2. Create a drawing using that view.
3. In the drawaing, select all the external edges and then use "convert entities" to make a sketch.
4. Trim the sketch to remove the open contours
5. Use the "section properties" function on the "tools" menu.

As I said, very laborious. Hopefully one of the MVPs can tell you the proper way to do it.

BTW, you may need to make it full-scale in order to get the proper projected area.

--------------------
How much do YOU owe?
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Yes, but depending on the complexity of the profile, it could be very simple or very tedious.

Create a plane and start a new sketch, then use the Convert Entities function to create an outline by selecting the outermost edges of the assy.

[cheers]
Helpful SW websites faq559-520​
How to find answers ... faq559-1091​
 
You can also use the Measure tool on a surface to find out the square units--that's a tad different than the true profile in the path of the wind, but much quicker.

Jeff Mowry
Reason trumps all. And awe trumps reason.
 
If you create a new plane with your wind vector as normal vector you can place the front plane of a new in-context part here. Do an offset entities, extrude to the thickness of 1 unit (eg, you want mm2 -> extrude 1mm). the result:

profile.jpg



Stefan Hamminga
EngIT Solutions
CSWP/Mechanical designer/AI student
 
little correction: "Do an offset entities" should read "Do a convert entities" offcourse

Stefan Hamminga
EngIT Solutions
CSWP/Mechanical designer/AI student
 
This is a very complicated assembly and would take weeks to convert indivdual entities.
 
Stefan, you gotta stop puttin the big pics in. The text streaaaaaaaaaaaaaaaaatches to the point you cant read it.

Not a huge fan of this,
but this is one of those save as part scenarios.
Save the assembly as a part
Do some work to combine stuff
Get rid of O dims.
Cut one half of the assembly away in the plane for profile.
Combine until everything it is one body
Find the centroid.

There are many other ways to skin this cat too.

RFUS
 
Try saving the assembly as a single part file.
Then project on your plane and convert entities.

Remember...
[navy]"If you don't use your head,[/navy] [idea]
[navy]your going to have to use your feet."[/navy]
 
Here's a thought:

1) Save the assembly as a part, selecting the exterior faces option

1a) Depending on the result of step 1, you may have to do some trimming or other surface operations to get a solid body.

2) Pattern the body a large number of times in the direction of the wind vector by a very small amount. Doing this will essentially yield a new solid body which shows your profile normal to the wind vector.

3) Cut the part such that one of the resulting cut planes is normal to your wind vector. The area of this face is your projected area.

This may be beyond the computing power you have, or you may run into boolean failures on the pattern, but it should get you very close, particularly if the resolution of your pattern is high enough.

Hope this helps,
Dave Gowans
 
OK then ....

Create planes which cut through the assy (perp to wind direction) at positions which cover the largest wind resistance.

Start a sketch on a plane, activate the Intersection Curve tool, then select the parts (from the 'manager' tree) which the plane cuts through. An outline of the part should appear in the sketch. Close the sketch.

Repeat that process for the other planes.

Now use the Convert Entities tool to "collect" all the sketches into one. Clean up using the Trim Entities and/or Extend Entities tools.

Then use the Tools > Section Properties to obtain the other info you want.

[cheers]
Helpful SW websites faq559-520​
How to find answers ... faq559-1091​
 
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