Regarding implementation fringe region technique in Cylinder2d code.

[atanuchaudhury1994@gmail.com]

Dear OpenLB team,

I got a paper in which they applied Smagorinsky and Fringe Region Technique in Cylinder2D. I tried to apply like this:
#include “fringe2D.h”
#include “fringe2D.hh”
//rest code
void prepareLattice…
//rest code
// Define the fringe region
Vector<T,2> extend( lengthX,lengthY );
Vector<T,2> origin;
IndicatorCuboid2D<T> fringeRegion(extend, origin);
superGeometry.rename(2,6,1,fringeRegion);

Define the reference state
AnalyticalConst2D<T,T> rhoF( 1 );
std::vector<T> velocity( 2,T( 0 ) );
AnalyticalConst2D<T,T> uF( velocity );

Create the Fringe2D functor
Fringe2D<T,DESCRIPTOR> fringe(uF, start, end, direction, lambdaMax, rise, fall);

Apply the fringe region in the collision step
sLattice.defineDynamics<FringeBGKdynamics>(fringeRegion, &fringe);

But this giving out error: cylinder2d.cpp:41:10: fatal error: fringe2D.h: No such file or directory
41 | #include “fringe2D.h”

What is the solution to this? Please help.

[FBukreev]

Hello,

You don´t need to add these includes into your setup. Just add into your setBoundaryValues function the following lines:

AnalyticalConst3D wantedVelocity(maxVelocityV[0],T(),T()); // the velocity that you want to take as reference for the fringe zone. The mass conservation must be held through that velocity.
Fringe3D fringeForceCoefficients(wantedVelocity, lz-10*ly/N, lz, 0., 0.008); //lz is the furter end of the fringe zone. lz-10*ly/N is the start point of the zone. 0 and 0.008 are the coefficients, you can look on their descriptions in the corresponding source files.
slattice.defineField(superGeometry, 5, fringeForceCoefficients); //here 5 is the Material Number of the fringe zone cells.

For MN 5 please take SmagorinskyLinearVelocityForcedBGKdynamics and add FORCE and V12 external fields into your descriptor.

[atanuchaudhury1994@gmail.com]

Thank you for the reply. But my contour is Cylinder2D, so should I use Frindge2D in place of Fringe3D here:

Fringe3D fringeForceCoefficients(wantedVelocity, lz-10*ly/N, lz, 0., 0.008); //lz is the furter end of the…

[mathias]

I dont have an example. Sorry, we connot give more detailed support here in the forum.

[Author]

Posts