[vauntedmango]

I am new to CFD but have recently been asked to look into generating a quasi-3d simulation. I was not able to find a lot of resources addressing what it is. The cfd-online best practice guide for turbomachinery states:

'A quasi-3D simulation is a 2D simulation in which extra source terms are used to account for the acceleration/deceleration caused by a changing channel height or growing end-wall boundary layers'

This makes sense, but I do not know how this would translate to the meshing/simulation process when setting it up. Any ideas?

[aero_head]

Originally Posted by vauntedmango

I am new to CFD but have recently been asked to look into generating a quasi-3d simulation. I was not able to find a lot of resources addressing what it is. The cfd-online best practice guide for turbomachinery states:

'A quasi-3D simulation is a 2D simulation in which extra source terms are used to account for the acceleration/deceleration caused by a changing channel height or growing end-wall boundary layers'

This makes sense, but I do not know how this would translate to the meshing/simulation process when setting it up. Any ideas?

A quasi-3D simulation is essentially a 2D mesh with 1 cell width in the third direction (i.e. z).

This needs to be done since CFX cannot solve a 2D simulation. From the reference: https://www.cfd-online.com/Wiki/Ansy..._simulation.3F

" From a 2D mesh of the geometry, extrude it one element in the normal direction. For a 2D planar simulation this would be one element in the normal vector direction, for a 2D axisymmetric simulation this would be sweeping a small angle with one element. For the planar mesh the extrusion should be approximately equal to the smallest element edge length in the model, for the axisymmetric mesh the sweep should be a small angle, maximum 5° but smaller if you want high accuracy.

In CFX-Pre you should set the top and bottom faces of the extrusion as symmetry planes. If you want to include swirl in the model use periodic boundaries. The remaining boundaries should be set as walls, inlets, openings and outlets to define the flow.

The CFX documentation discusses 2D simulations and it is recommended you read it before proceeding."