Velocity boundary condition values leak across the edge of an Inlet Splitter

Mar 3, 2012


Issue:

An inlet is split into two surfaces by an edge belonging to a Surface Part acting as a flow splitter oriented normal to the inlet. Different velocity values are applied to the two surfaces that share the common edge. During the simulation, the specified velocity values on one of the inlet surfaces appear to “lead” across the dividing edge so that the wrong value appears on certain nodes in the other surface.

 

Solution:

Solution

This occurs because of an ambiguity on the common edge between the two surfaces. Because only one of the specified velocity values can be mapped to the nodes on the edge, the incorrect value occurs in one of the surfaces when the Boundary Layer elements are created during mesh generation.

Instead of a velocity boundary condition, apply a mass flow rate or volume flow rate boundary condition to the two surfaces. This eliminates the ambiguity at the common edge.

 

Products:

Simulation CFD

Versions:

2010;2011;2012;2013;2014

Discuss