78 505
Assignments Done
99,5%
Successfully Done
In September 2019

# Answer to Question #27721 in Astronomy | Astrophysics for Omkareshwar Jha

Question #27721
Is it possible to make adibatic wall????
Adiabatic walls are implemented in Palabos, according to the following idea: the wall implements a boundary condition for the temperature, but the value of the temperature to be imposed on the wall is copied from the nearest neighbor at each iteration. The effect of this is to have a zero temperature gradient along the wall normal, which means, an adiabatic wall.
Use it with care, though, because this boundary condition has not yet been tested very thoroughly. In particular, it doesn't seem to be very stable, numerically, at high Rayleigh number.

// The lattice of the navier-stokes solver
MultiBlockLattice3D<T, NSDESCRIPTOR> nsLattice (
nx,ny,nz,new NSDYNAMICS<T, NSDESCRIPTOR>(nsOmega) );

// The lattice of the temperature solver

// .. at this place, create the coupling between temperature and fluid, as usual.

OnLatticeBoundaryCondition3D<T,NSDESCRIPTOR>*
& nsBoundaryCondition = createLocalBoundaryCondition3D<T,NSDESCRIPTOR>();
&

// All outer walls of the rectangular domain shall implement a velocity condition for
// the fluid, and a fixed temperature condition for the temperature.
nsBoundaryCondition -> setVelocityConditionOnBlockBoundaries(nsLattice);

// On one selected plane (the x-z plane at y=0), turn the temperature condition

Box3D adiabaticWall(0,& nx-1, 0, 0, 1, nz-2);

xint processorLevelBC = 1;
integrateProcessingFunctional (

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!