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[sailaja]

I imported my geometry in the design modeler from AutoCAD. The drawing unit in AutoCAD was in meter. But in design modeler the unit of geometry is showing in mm (for example 1.3 m width is showing 1.3 mm in design modeler). I don't know why is this difference. I selected meter as unit in design modeler also but still my geometry unit is in mm. How can I make it to original unit to m ? The geometry is attached below .Suggestion please

Thank You in Advance.

geometry.PNG

[Keyur Kanade]

As Ansys Staff, we can not download attachments. Please upload images using upload image functionality.
You can change units in DM


You can scale geometry in DM.

Regards Keyur
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[sailaja]

Thank you . Did It.

[Rob]

To add, if you do get the wrong units, mesh to suit the wrong scale and fix in Fluent. Scaling CAD can cause problems depending on when/how tolerances are calculated. I suspect most staff have seen/made this mistake. I think the worst I've seen is a room with 140m/s updrafts: 9km was a little taller than planned.....

[sailaja]

Hi Rob you mean I need to scale my mesh size in scale mesh in fluent solver not the geometry in design modeler ? for example my geometry width is 1.35 m and its showing 1.35 mm. Now the thing is if I generate mesh of 0.01 mm and scale in fluent solver in scale mesh by 1000 then my mesh size will be 10mm , right? So, when I open solver my geometry which is in mm when imported to ANSYS will be automatically in m? That's why I have to scale my mesh size only ?

Than you in Advance.

[Rob]

Opening CAD in another tool means trusting the conversion software: which can do what you're seeing where mm-m-km get muddled up. In your case, using a small cell size and then scaling in Fluent means the cells will also scale. "Ansys" is the company, you'll be reading geometry into SpaceClaim/DesignModeler and then Ansys (Workbench) Meshing/Fluent Meshing then Fluent. Don't worry too much what size Fluent thinks, just check and then adjust the scale (SCALE not UNITS) to ensure your domain is the correct size.

[sailaja]

Thank you .