# creating cylindrical coordinate system and selecting nodes in an area within certain angular limits and applying pressure as an

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Hi guys,

I am a PG student in Mechanical engineering and I am doing a project on automobile alloy wheel and I want to do structural analysis on it.

In the static analysis the pressure load is to be applied as cosine function on the bead seats of the rim through an angle of 80 degrees. So, first I have to create a cylindrical coordinate system and then nodes within the angular limits is to be selected. I don't know how to do it in Hypermesh.

I tried to export the model in Ansys. But I could not apply pressure load on the model imported from Hypermesh in Ansys.

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Hi,

To define cylindrical system, enter panel Analysis/system, switch "rectangular" to "cylindrical"

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Hi..

Thanks for the help..

I could create the cylindrical coordinate system, but I cannot select the nodes between the angular limits on the surface.

Please tell me how to do that..

Vishnu

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Hi Vishnu

just draw a line, copy it and rotate 80deg then select nodes between that two lines

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Hi,

I could select the required nodes. Thank you so much..

Now, my problem is to apply pressure on these nodes as an equation. The pressure is to be applied in cylindrical co-ordinate system because its magnitude varies with the angle.

The equation is "pressure, p= 2.5*{cos(2.25*t)}, where t- angular co-ordinate."

Regards,

Vishnu

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Hi Vishnu

on panel Analysis/pressure, change "magnitude" to "equation" and type in your equation:

2.5*cos(2.25*y)

select "system" point to the cylindrical system

pressure is applied to elems, so select elems attached to the nodes

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Hi Tinh,

I saw the "equation" option in the analysis panel which only comes for "elements".

But my problem is to select the elements attached to the nodes.

How can I select 3D elements attached to required nodes or surfaces?

I also tried the path "elements--> by geometry--> surfaces--> by face-->(selected required surfaces)". But it didn't work.

Regards,

Vishnu

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Hi,

Are there too many elements need be selected? if manual selection is tedious with you, you can:

- Shift F5, switch to "find attached" to find elements attached to the nodes, save found elems

- On pressure panel, select elems by "retrieve"

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Hi Tinh,

Thank you so much for the help.

I have completed the structural analysis successfully.

Regards,

Vishnu.V.A

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Hi,

I am having a similar problem. I have an arbitrary shape that I'd like to select nodes on based on angle. Could someone elaborate on how to do this? I've set up a cylindrical coordinate system and want to select nodes by r. Thanks for the help.

-Becca

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hi,

when you selecting nodes, hold down shift and press mouse button from hm11 there is an option for select entities inside/outside of a circle

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Thank you for your quick response. Your suggest doesn't seem to work for my application, it just selects nodes in a circle. I'd like to be able to input an angle r from the cylindrical system, and have hypermesh select all nodes at that angle from the origin. Is this possible?

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yeas, ofcourse it is possible, but not available. just make sure you assign cyl-coodinate system to the nodes then you can select them by local x, y, z ( phi, r, z)

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Hi

I am able to create the coordinate system. How do I get the output in the new system?

Is the best method to choose axis in hyperview?

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Hi mramakri,

Change the Resolved in option to User system and select the system you created, to get the output in the new system as shown in the below image.

Thank you

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Thanks @Premanand Suryavanshi

How do I relate the x,y,z in result type to the user system. In my case, its cylindrical. Is there a way to figure out the the corelation between x,y,z and r,t,z?

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Hi mramakri,

The results along X-direction relates to r-co-ordinate, Y-direction to t-co-ordinate and Z to z

Thank you

mramakri likes this

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On 2/3/2013 at 10:45 PM, tinh said:

Hi Vishnu

just draw a line, copy it and rotate 80deg the﻿n se﻿l﻿ect nodes be﻿tween that two lines

Hello Tinh,

How do I make selection of nodes between lines (surfaces for my case). Thank you.

Regards,

Emre

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