Meshing Thin Bodies

- February 21, 2020 at 9:21 pm
  
  sarin
  Subscriber
  
  Hi,
  
  I have a half pipe structure which is 54inch dia, 20ft long and .25inch thick. Whats the best way to mesh this body. Sweep method gives me only one layer of mesh. Body sizing with .125 inch thickness will make too many elements.
- February 21, 2020 at 9:32 pm
  
  peteroznewman
  Subscriber
  
  Hi sarin,
  
  The best way to mesh this thin body is to use Shell Elements.
  
  Go back to either SpaceClaim (best) or DesignModeler or your CAD system, and create midsurface geometry.
  
  There is a function that will automatically create the midsurface from the solid body in SC and DM.
  
  You bring this surface into Mechanical and assign the 0.25 inch thickness to the surface as well as the material.
- February 21, 2020 at 9:57 pm
  
  sarin
  Subscriber
  
  Thanks Peter, I will try that way. So if i use one layer of mesh after doing sweep or automatic methods and run the analysis, the results wont be accurate ?. Can you please share ur opinion
- February 21, 2020 at 10:08 pm
  
  peteroznewman
  Subscriber
  
  Do not use one layer of solid elements on thin solid geometry. There is a special element, SOLSH190 that has some ability to do this, but even that needs more than one element for high precision.
  
  Since you have a half pipe, you could define the Sweep direction by picking the inside face as the Source face, then you can dictate 2 or more elements along the sweep direction, which is through the thickness. At the same time, you can do Face Meshing on the inside face to force a quads on that face, and finally, you can do two edge sizings on the four edges of the inside face. You can put smaller element size on the half circles at each end, and larger element size along the length of the half pipe.
- February 21, 2020 at 11:07 pm
  
  sarin
  Subscriber
  
  Thanks Peter