Suspected division by zero on velocity reported by point probe

dahicke · June 27, 2013, 00:14

Hi All,

I am doing a mesh refinement study with a DFBI overset mesh and am trying to get velocity values (i,k) via two maximum reports vs. iteration. I picked a point in the region of interest created a derived part, created two maximum reports getting the i velocity and k velocity at that point, created the monitors for each report, and then put them into an XY graph plot.

It works fine except that there are time when the values seem to be divided by zero for 4 or 5 iteration and some as long as about 40 iterations.

Is this a bug in the point probe, maybe a cell to point probe alignment problem?

I would expect this behavior early in convergence, but not at the end.

Thanks,

Dave

dahicke · July 4, 2013, 03:16

I attached a plot of two points on a 2.5D mesh one behind the other. Both points appears to get a divide by zero; one more than the other.

hull-1ms-8p0H-67mlambda-50mh-2.5D_Fluid Velocity at both points 0,0 1_0.25 -5.jpg

June 27, 2013, 00:14	Suspected division by zero on velocity reported by point probe	#1
dahicke New Member David Hickerson Join Date: Aug 2009 Location: Parker, CO Posts: 17 Rep Power: 17	Hi All, I am doing a mesh refinement study with a DFBI overset mesh and am trying to get velocity values (i,k) via two maximum reports vs. iteration. I picked a point in the region of interest created a derived part, created two maximum reports getting the i velocity and k velocity at that point, created the monitors for each report, and then put them into an XY graph plot. It works fine except that there are time when the values seem to be divided by zero for 4 or 5 iteration and some as long as about 40 iterations. Is this a bug in the point probe, maybe a cell to point probe alignment problem? I would expect this behavior early in convergence, but not at the end. Thanks, Dave

July 4, 2013, 03:16	Here is an image of the problem	#2
dahicke New Member David Hickerson Join Date: Aug 2009 Location: Parker, CO Posts: 17 Rep Power: 17	I attached a plot of two points on a 2.5D mesh one behind the other. Both points appears to get a divide by zero; one more than the other. hull-1ms-8p0H-67mlambda-50mh-2.5D_Fluid Velocity at both points 0,0 1_0.25 -5.jpg

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