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Tangential component of gradient of scalar field at surface

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Old   March 23, 2007, 07:14
Default Hi, To implement a thermo
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Thomas Jung
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Hi,


To implement a thermocapilllary convection boundary condition, I need the gradient of temperature tangential to the surface. I know how to get the temperature patchfield, and also the gradient normal to the surface, but how to get the tangential component?
fvc::grad seems not to work on fvPatchFields, I tried this:

const fvPatchField<scalar>& TB =
lookupPatchField<volscalarfield,>("T");

const fvPatchField<vector> TGrad=fvc::grad(TB);

results in:

no matching function for call to 'grad(const Foam::fvPatchField<double>&

I could declare and compute temperature gradient as a volfield all over the volume, but I thought this should only be my last ressort, in order to save memory.

Thank you very much for any hint!

Thomas
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Old   March 23, 2007, 08:58
Default Unfortunately, calculating the
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Eugene de Villiers
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Unfortunately, calculating the volume gradient is the only out-of-the-box option. To calculate patch tangential gradients would require a finiteArea formulation, which is not currently integrated to the level that would make it simple to employ.
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Old   June 4, 2013, 02:27
Default Any luck?
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Srivathsan N
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Hi Thomas,

Were you able to implement grad T tangentially? I'm also having a problem with that.


Regards

Srivaths
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Old   June 4, 2013, 02:51
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Ehsan
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hi Srivathsan
Why do you need tangential component instead of normal one?
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Old   June 4, 2013, 05:07
Default want grad T along a curved surface
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Hi ehsan

I am also working on a similar problem as Thomas. I would like to have the gradient of temperature tangential to the surface for simulating thermo-capilary effect on a curved surface.
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Old   July 4, 2013, 07:13
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Quote:
Originally Posted by eugene View Post
Unfortunately, calculating the volume gradient is the only out-of-the-box option. To calculate patch tangential gradients would require a finiteArea formulation, which is not currently integrated to the level that would make it simple to employ.
Hi Eugene,

Is it possible to take the definition of fixedGradient boundary condition and map it along a patch (to get a gradient along the surface)?

What does transformFvPatchField do? Does it help here?

Thanks in advance.
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