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Dave November 4, 2005 14:07

Warnings
 
I have this warnings in run history

*** WARNING #038 *** UNNORMALISED RESIDUAL CANNOT BE REDUCED TO 1.000000E-06 IN EQ: PCOR ROUND-OFF ERROR RESCUE NOT ATTEMPTED; SOLUTION RETURNED WITHOUT UPDATE

*** WARNING #001 *** FLUID INFLOW DETECTED AT SOME OUTFLOW BOUNDARIES WHERE MASS FLUXES ARE FORCED TO ZERO.

F THIS CONDITION PERSISTS, YOUR RESULTS MIGHT BE WRONG THE OUTFLOW BOUNDARY MIGHT NOT BE WELL SPECIFIED OR THE GRID MIGHT BE TOO COARSE NEAR THE OUTFLOW BOUNDARY

** WARNING #090 *** VALUE ELOG*YPLUS OR ELOG*EFFVIS/(CAPPA*VISCOS) IS LESS THAN 1.1 AT 444 CELLS.UPLUS=YPLUS LAW IS USED. IF THIS SITUATION PERSISTS, INCORRECT RESULTS MAY BE OBTAINED.

Any help should be apreciated

Jamie November 9, 2005 14:31

Re: Warnings
 
error 038: the pcor unnormalised residual was below the residual tolerance on the first sweep

error 001: you have an outlet boundary in an area of recirulation and flow is trying to get back in. If you get it only a couple of times at the beginning of the analysis, you can ignore it. If you get it all the time that it must be dealt with. Either change it to a pressure boundary, which doesn't mind if flow goes in or out, or move the outlet farther downstrem.

error 090: your y+ values are too low for the turbulence model you are using and the near wall mesh is too fine. you could switch to a low Re model with the hybrid wall option on.

JV November 9, 2005 22:08

Re: Warnings
 
Thanks Jamie for your help. An additional doubt, when i change to pressure boundary at outlet, what is the difference in selecting: None, Zero Grad or TI/Lengh for the Turb. switch. My model is turbulent and i am using high reynolds ke with k/epsilon at inlet boundary.


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