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Old   October 16, 2006, 00:17
Default Hello All, I am wondering i
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Shaun Cooper
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Hello All,

I am wondering if it is possible to get access to the spatial gradient constituents of the divergence operator.

What I really want is to be able to look at the three seperate constituents of the divergence of the velocity (i.e du/dx, dv/dy, dw/dz). How can I access these so that I can print these fields out at each time step?

Thanks in advance,

Shaun
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Old   October 16, 2006, 00:26
Default Calculate fvc::grad(U) and tak
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Hrvoje Jasak
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Calculate fvc::grad(U) and take the xx, yy and zz component.

Hrv
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Old   October 16, 2006, 00:52
Default Thanks for the advice thus far
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Shaun Cooper
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Thanks for the advice thus far however I have the following problem.

I have created a field called gradU that is a volTensorField. It is written out at each time step. From this field I was then going to take the individual constituents I require. For example I created a volScalar field called streamwise and at the end of the application (just before runTime.write(); at the end of the time step) I have written the following:

streamwise = gradU.xx();

When I go to compile this I receive the following error:

newThermSolver.C:132: error: 'struct Foam::volTensorField' has no member named 'xx'

I am not sure what I have done wrong. Can someone help me with this error? This looks like an example that can be found on pg P-23 of the programmers guide.

The tensorfield gradU does write out at each time-step and does appear to work correctly.

Thanks,

Shaun
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Old   October 16, 2006, 02:05
Default I am not sure what I have done
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Hrvoje Jasak
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Quote:
I am not sure what I have done wrong
You didn't check the header files, you didn't look for example codes that may be using the same thing, you didn't check the documentation, you didn't even search this forum.

OK, enough of that - I think you've got the message :-)

gradU.component(tensor::XX);

Hrv
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Old   October 16, 2006, 04:20
Default Sorry, Sorry, Sorry, Sorry.
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Shaun Cooper
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Sorry, Sorry, Sorry, Sorry.

Thanks for you help!
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