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bk July 19, 2005 00:10

Information about Warning message
 
In many cacualtion post file(*.info, *.run ...), we can find some warning message like this ----------------------------------------------------- *** WARNING #090 *** VALUE ELOG*YPLUS OR ELOG*EFFVIS/(CAPPA*VISCOS) IS LESS THAN 1.1 AT 100 CELLS.

UPLUS=YPLUS LAW IS USED. IF THIS SITUATION PERSISTS, INCORRECT RESULTS MAY BE OBTAINED. *** WARNING #090 *** VALUE ELOG*YPLUS OR ELOG*EFFVIS/(CAPPA*VISCOS) IS LESS THAN 1.1 AT 100 CELLS.

UPLUS=YPLUS LAW IS USED. IF THIS SITUATION PERSISTS, INCORRECT RESULTS MAY BE OBTAINED.

MAXIMUM COURANT NUMBER = 1.150E-03 AT CELL 7900 MEAN COURANT NUMBER = 1.130E-04

*** WARNING #052 *** INITIAL RESIDUAL BELOW ROUND-OFF ERROR LIMIT SOLUTION ,EQ: UMOM

*** WARNING #052 *** INITIAL RESIDUAL BELOW ROUND-OFF ERROR LIMIT SOLUTION ,EQ: VMOM -----------------------------------------------------

How can I find the information for each warning #?

Richard July 19, 2005 03:40

Re: Information about Warning message
 
The WARNING #090 means that some of your cells are too close to the wall for the high Reynolds number wall function to be valid. You could choose to ignore this (maybe 100 cells is not many), or coarsen the mesh, or try the hybrid wall model, or refine the mesh everywhere and use a low Reynolds number model. Lots of possibilities.

The WARNING #052 means that the U and V fields at the start of the iteration/time-step already satisfy the solver, i.e. these fields are not changing. This means either you've made a mistake, or the fields have fully converged, or whatever is forcing the flow in those directions is so small as to be indistinguishable from the the round-off error.


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