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individual shape function under "weak form PDE" ??
Posted 26.05.2014, 08:35 GMT-4 Fluid & Heat Version 4.4 0 Replies
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I use "weak form PDE" within the "math mode" for solving the Navier-stokes equation.
I use 2D within xy-world.
Basically it works, though the linear part of the solution does not really converge.
My problem: I could not find a button, where I can specify a quadratic
shape function for velocity and temperature, but a linear one for the pressure.
For a "weak form" node, there is a "Global"-Item for discretisation, which is valid for the whole equation system. I have let it be quadratic, but for pressure I need a linear one.
I get fine contour lines for velocity and temperature, but the pressure contour lines are totally pixeled, I mean anyhow destroyed.
Also, to set a pressure boundary value (like zero) I would like to take only a point at the boundary, but the "weak form" node offers for Dirichlet conditions under 2D xy-world only boundary line segments.
Is this due to my unfortunate quadratic shape function of my pressure variable??
Thank you very much in advance!
Regards
Klaus
Hello Klaus Boettcher
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