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TUM June 8, 2001 11:20

Geometry of straight pipe
Hello I have problems about how to create the straight pipe with slope 1.19 degree. I do not understand about the axis that i must input the coordinate in the axis block. Please suggest the way to create this model. I just study CFX-5 for one week. Thank you

Dan Williams June 10, 2001 11:37

Re: Geometry of straight pipe
If I had to do this I'd create a circle, rotate it by 1.19 degrees, and then extrude the circle the desired length along a direction vector which gives you a 1.19 degree slope.

Maybe you tried this already?


aoyi July 16, 2001 05:36

Re: Geometry of straight pipe

I have a similar problem like that of TUM. Dan suggests that you create a circle and extrude. How do you do this???

I can only extrude a surface. Further, I am unable to create surface edges from a circle because, by defualt the surace should have at least 3 edges from 3 curves.

All i did was to rotate a point on XY plane 4 times in oder to create a circle(according to example 2 of Build). This worked but is there a shorter method?


aon a circle beneed to re

janyatoyo July 16, 2001 06:32

Re: Geometry of straight pipe

how do you extrude a circle?


Dan Williams July 16, 2001 21:15

Re: Geometry of straight pipe
You can create a curve which is a circle by simply rotating a point about a center. I think it's under Create->Curve->Revolve.

After that you need to rotate the circle by the desired angle. Transform->Rotate (or something like that), then create a surface by extruding along a direction vector. I think it's under Create->Surface->Extrude.

You'll need to add end surfaces to enclose the geometry so that you can make a b-rep. I'd just use trimmed surfaces for these.

Also, be careful if you are using CFX-5 before version 5.4. Before that the surface mesher could not mesh periodic (closed) surfaces. If that's the case then you'll need to split the original circle into two pieces.


aoyi July 17, 2001 07:09

Re: Geometry of straight pipe
Hi Dan,

Thanks for responding. For you to create a surface in cfx4.3,(Build) by default you need at least 3 edges, as i said earlier. It was not clear from your contribution how one can do this from a CIRCLE. tHAT IS IF YOU DO NOT STEP BY STEP rotate a point the create curve...revolve thing.

Under which menu option (in cfx4.3 build) do you add end surfaces?

tum July 18, 2001 11:12

Re: Geometry of straight pipe
i have been already to create circle>revolve... After that i exclude the surface of that circle to be the straight. Thank you

Dan Williams July 18, 2001 20:33

Re: Geometry of straight pipe
Sorry, I've never done this in CFX-4, so I'm not sure what the procedure would be. The original post was regarding CFX-5.


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