View Issue Details
ID | Project | Category | View Status | Date Submitted | Last Update |
---|---|---|---|---|---|
0002846 | OpenFOAM | Bug | public | 2018-02-14 22:24 | 2018-02-16 23:11 |
Reporter | tnnandi | Assigned To | henry | ||
Priority | high | Severity | major | Reproducibility | always |
Status | closed | Resolution | unable to reproduce | ||
Platform | GNU/Linux | OS | Ubuntu | OS Version | 14.10 |
Summary | 0002846: Inconsistent wall BC while using RANS/LES wall functions | ||||
Description | Several tutorials using wallfunctions with RANS/LES turbulence models use no-slip BC for U (fixedValue with value uniform (0 0 0)). This is perhaps not correct, as these wall functions have been developed for cases where the first cell-center adjacent to the wall to be outside the viscous sublayer. This requirement contradicts the no-slip condition (which can only be used if the flow is calculated upto the viscous sublayer). For example, in the windAroundBuildings tutorial, the near-wall eddy viscosity is calculated using the nutkWallFunction. Apart from the eddy viscosity, the wall velocity is also required directly to calculate the terms which involve velocity gradient calculation (e.g. convection and diffusion terms) for the cells adjacent to the wall. Other tutorials with similar BCs are cavity and airfoil2D Fixing the value of velocity to (0 0 0) at the wall may interfere with the velocity gradient calculation for the cells on the wall. | ||||
Tags | No tags attached. | ||||