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Unsteady Wall Statistics

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Old   March 20, 2020, 10:40
Default Unsteady Wall Statistics
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Hi all, I have lost 6 days of simulation in a cluster because Fluent didnīt collect statistics for my wall shear stresses.

As you can observe in the attached images I have selected the options to collect statistics for wall statistics but when I check my contours of Mean X-Wall Shear Stress, my values are 0, meaning that it didnīt collect any statistical data. It is not an inviscid case, check the other image where I have values for the instantaneous x-wall shear. However, I have data for the Mean Pressure Coefficient, which is inside wall statistics.

I am very confused with this, why isnīt fluent collecting statistics of my wall shear stresses??
Attached Images
File Type: jpg Instantaneous X-Wall Shear.jpg (123.4 KB, 13 views)
File Type: jpg Mean X-Wall Shear.jpg (124.2 KB, 13 views)
File Type: jpg Mean Pressure Coefficient.jpg (121.9 KB, 12 views)
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Old   March 20, 2020, 11:09
Default Wall Statistics
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Though it should get interpolated, but did you try disabling Node and Global values while plotting mean x-shear stress?
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Old   March 20, 2020, 12:27
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Since it is a transient simulation, the simulation needs to be run for a while in order to collect data for having sufficient data in order to generate averaged quantities. There isnīt any interpolation here.
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Old   March 20, 2020, 14:24
Default Interpolation
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Running for at least a couple of time steps is obvious requirement. But that you've already done; you ran it for six days. But while plotting contours, you have Node values as well as Global scale selected. These should not cause any issues as such because although the sampling is done at centers of the cells yet data interpolation is done for the nodes. But sometimes, some of the variables are 0 on the walls. Stress should not be zero but there's no harm in checking if the actual values are also 0 or not. That's why I suggested you to plot contours with Node values and Global scale deselected.
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