[fisch]

Hello,

i want to change my boundary conditions during the run of my solver.
So specifying Dirichlet BC was more or less easy to implement (overwriting the boundaryFields of the variables).

Now I want to overwrite the value of the fixedGradient BC during the runtime for other variables.
Is this possible and easy to access?

Thank you for any advice,

rupert

[gschaider]

Originally Posted by fisch

Hello,

i want to change my boundary conditions during the run of my solver.
So specifying Dirichlet BC was more or less easy to implement (overwriting the boundaryFields of the variables).

Now I want to overwrite the value of the fixedGradient BC during the runtime for other variables.
Is this possible and easy to access?

Thank you for any advice,

rupert

Use groovyBC? Unless you really want to write your BC in C++

[fisch]

thanks bernhard for the quick reply,

there are unfortunately questions left:
Is there no problem using the groovyBC specifying values for "valueExpression" and for "gradientExpression" ???
I thought that it is the only way to specify (e.g. using) simpleFoam either the velocity as dirichlet and the pressure as neumann or the other way around. Now it seems that i can specify on both fields dirichlet and neumann!?

Can you explain that to me?

One more thing: What is, if i dont specify one of these two keywords ( "valueExpression" or "gradientExpression)??

thanks a lot,
rupert

[gschaider]

Originally Posted by fisch

thanks bernhard for the quick reply,

there are unfortunately questions left:
Is there no problem using the groovyBC specifying values for "valueExpression" and for "gradientExpression" ???
I thought that it is the only way to specify (e.g. using) simpleFoam either the velocity as dirichlet and the pressure as neumann or the other way around. Now it seems that i can specify on both fields dirichlet and neumann!?

Can you explain that to me?

groovyBC is a child class of the mixed-BC. Have a look in the USerGuide for that

Originally Posted by fisch

One more thing: What is, if i dont specify one of these two keywords ( "valueExpression" or "gradientExpression)??

thanks a lot,
rupert

That is described here:

http://openfoamwiki.net/index.php/Co...s_in_the_patch

[fisch]

Thanks a lot Bernhard,
it seems that it works.

rupert