Reducing Tube from 3D to 2D

Sullo_Saan

Hello everyone!

SimLab with AcuSolve is my first experience with thermal and flow simulations, so I am starting from simpler geometries, before moving to anything more complicated. The first thing I need to simulate is the flow and heating of initially room-temperature gas in a hot narrow tube.

Of course, it is possible to make a 3D model of a tube. But at least in theory, the problem could be reduced to 2D. In cylindrical coordinates, only the radius (r) from the axis and the length along the tube (z) matter. The angle from the axis (phi) is irrelevant.

I have looked for ways to make a 2D model with a 2D mesh, but I cannot find any. So the question is: in SimLab, is there a way to make a 2D model of a tube?

acupro

The CFD solver behind SimLab - AcuSolve - does not have a planar solver, so the mesh must be one element thick for a 2D solution. Then you would probably use symmetry boundary conditions on the faces where you don't want flow crossing. Typically extruding the mesh would be the approach - to get something like the image below - where the left is the inlet, top and bottom are the pipe walls, and the front and back (not seen) are symmetry. The boundary layers could also be tria elements. This tutorial outlines the steps in SimLab to do this mesh extrusion with boundary layer imprinting.

https://help.altair.com/hwcfdsolvers/acusolve/topics/tutorials/acu/acu_3000_intro_sl_r.htm