Field Function Conditional Expressions

shanefarrell · February 19, 2013, 10:20

Hi,
Im trying to use field functions to refine my mesh, but my conditional expression for my refinement table is written incorectly. I want my mesh to be finer in the areas where the velocity is over 0.4m/s and also in the areas where the temperature is over 293K. The two expressions shown below work fine individually but i need to combine the two to generate the one mesh refinement table...any ideas?

($RelativeVelocityMagnitude > 0.04) ? 0.038 : 0.08
($Temperature > 293) ? 0.038 : 0.08

Thanks in advance

lava12005 · February 19, 2013, 21:02

Try using the and '&&' logical operator?
Maybe this?
(($RelativeVelocityMagnitude > 0.04) && ($Temperature > 293)) ? 0.038 : 0.08

shanefarrell · February 20, 2013, 09:36

Thanks for the reply. I used the logical operator '&&' but this only refines the mesh in the areas where both the velocity is > 0.4 and the temperature is > 293. I need to refine the mesh in the areas where either of these conditions are met.

lava12005 · February 20, 2013, 09:55

Then you can use the OR logical operator '||' since if either of these requirement are met, then it will refine the mesh.
So it should be
(($RelativeVelocityMagnitude > 0.04) || ($Temperature > 293)) ? 0.038 : 0.08

shanefarrell · February 21, 2013, 09:44

It worked perfectly, thanks very much.

February 19, 2013, 10:20	Field Function Conditional Expressions	#1
shanefarrell New Member Shane Farrell Join Date: Nov 2012 Posts: 5 Rep Power: 13	Hi, Im trying to use field functions to refine my mesh, but my conditional expression for my refinement table is written incorectly. I want my mesh to be finer in the areas where the velocity is over 0.4m/s and also in the areas where the temperature is over 293K. The two expressions shown below work fine individually but i need to combine the two to generate the one mesh refinement table...any ideas? ($RelativeVelocityMagnitude > 0.04) ? 0.038 : 0.08 ($Temperature > 293) ? 0.038 : 0.08 Thanks in advance

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February 19, 2013, 21:02		#2
lava12005 Senior Member KHB Join Date: Aug 2010 Location: Singapore Posts: 118 Rep Power: 15	Try using the and '&&' logical operator? Maybe this? (($RelativeVelocityMagnitude > 0.04) && ($Temperature > 293)) ? 0.038 : 0.08

February 20, 2013, 09:36		#3
shanefarrell New Member Shane Farrell Join Date: Nov 2012 Posts: 5 Rep Power: 13	Thanks for the reply. I used the logical operator '&&' but this only refines the mesh in the areas where both the velocity is > 0.4 and the temperature is > 293. I need to refine the mesh in the areas where either of these conditions are met.

February 20, 2013, 09:55		#4
lava12005 Senior Member KHB Join Date: Aug 2010 Location: Singapore Posts: 118 Rep Power: 15	Then you can use the OR logical operator '\|\|' since if either of these requirement are met, then it will refine the mesh. So it should be (($RelativeVelocityMagnitude > 0.04) \|\| ($Temperature > 293)) ? 0.038 : 0.08

February 21, 2013, 09:44		#5
shanefarrell New Member Shane Farrell Join Date: Nov 2012 Posts: 5 Rep Power: 13	It worked perfectly, thanks very much.