void setBoundaryValues(LBconverter<T> const* converter,
BlockStructure2D<T,DESCRIPTOR>& lattice, int iT){
if(iT==0){
const int nx = lattice.getNx();
const int ny = lattice.getNy();
// set initial values: v = [0,0]
for (int iX=0; iX<nx; ++iX) {
for (int iY=0; iY<ny; ++iY) {
T vel[] = { T(), T()};
lattice.get(iX,iY).defineRhoU((T)1, vel);
lattice.get(iX,iY).iniEquilibrium((T)1, vel);
}
}
// set non-zero velocity for upper boundary cells
for (int iX=1; iX<nx-1; ++iX) {
T u = converter->getLatticeU();
T vel[] = { u, T() };
lattice.get(iX,ny-1).defineRhoU((T)1, vel);
lattice.get(iX,ny-1).iniEquilibrium((T)1, vel);
}
// Make the lattice ready for simulation
lattice.initialize();
}
}
void prepareLattice(LBconverter<T> const* converter,
BlockStructure2D<T,DESCRIPTOR>& lattice,
Dynamics<T, DESCRIPTOR>& bulkDynamics,
OnLatticeBoundaryCondition2D<T,DESCRIPTOR>& bc ){
const int nx = lattice.getNx();
const int ny = lattice.getNy();
const T omega = converter->getOmega();
// link lattice with dynamics for collision step
lattice.defineDynamics(0,nx-1, 0,ny-1, &bulkDynamics);
// left boundary
bc.addVelocityBoundary0N( 0, 0, 1,ny-2, omega);
// right boundary
bc.addVelocityBoundary0P(nx-1,nx-1, 1,ny-2, omega);
// bottom boundary
bc.addVelocityBoundary1N( 1,nx-2, 0, 0, omega);
// top boundary
bc.addVelocityBoundary1P( 1,nx-2,ny-1,ny-1, omega);
// corners
bc.addExternalVelocityCornerNN( 0, 0, omega);
bc.addExternalVelocityCornerNP( 0,ny-1, omega);
bc.addExternalVelocityCornerPN(nx-1, 0, omega);
bc.addExternalVelocityCornerPP(nx-1,ny-1, omega);
}
void getResults(BlockStructure2D<T,DESCRIPTOR>& lattice,
LBconverter<T>& converter, int iT) {
const T lx = 2.;
const T ly = 1.;
const int saveIter = 2000;
const int statIter = 200;
const int imSize = 400;
if (iT%statIter==0) {
T middleU[2];
lattice.get(converter.numNodes(lx)/2, converter.numNodes(ly)/2).computeU(middleU);
OstreamManager cout(std::cout,"plotStatistics");
T dx = converter.getDeltaX();
T dt = converter.getDeltaT();
cout << "iteration=" << setw(5) << iT;
cout << "; t=" << setprecision(3) << setw(6)
<< iT*converter.getDeltaT();
cout << "; E=" << setprecision(10) << setw(15)
<< lattice.getStatistics().getAverageEnergy()*dx*dx/dt/dt;
cout << "; rho=" << setprecision(8) << setw(11)
<< lattice.getStatistics().getAverageRho();
cout << "; uMax= " << setprecision(8) << setw(11)
<< middleU[0]*dx/dt;
cout << endl;
}
if (iT%saveIter==0) {
DataAnalysisBase2D<T,DESCRIPTOR> const& analysis = lattice.getDataAnalysis();
ImageWriter<T> imageWriter("leeloo");
imageWriter.writeScaledGif(createFileName("p", iT, 6),
analysis.getPressure(), imSize, imSize);
imageWriter.writeScaledGif(createFileName("u", iT, 6),
analysis.getVelocityNorm(), imSize, imSize);
ofstream *ofile = 0;
if (singleton::mpi().isMainProcessor()) {
ofile = new ofstream((singleton::directories().getLogOutDir()+"centerVel.dat").c_str());
}
for (int iY=0; iY<lattice.getNy(); ++iY) {
T dx = converter.getDeltaX();
T dt = converter.getDeltaT();
T analytical = poiseuilleVelocity(iY, converter);
T numerical[2];
lattice.get(lattice.getNx()/2, iY).computeU(numerical);
if (singleton::mpi().isMainProcessor()) {
*ofile << iY*dx << " " << analytical*dx/dt
<< " " << numerical[0]*dx/dt << "\n";
}
}
delete ofile;
}
}
void setBoundaryValues(LBconverter<T> const&converter,
BlockStructure2D<T,DESCRIPTOR>& lattice, int iT){
int nx = lattice.getNx();
int ny = lattice.getNy();
if(iT==0){
for (int iX=0; iX<nx; ++iX) {
for (int iY=0; iY<ny; ++iY) {
T force[2] = { poiseuilleForce(converter), T() };
lattice.get(iX,iY).defineExternalField (
DESCRIPTOR<T>::ExternalField::forceBeginsAt,
DESCRIPTOR<T>::ExternalField::sizeOfForce,
force
);
}
}
/// Make the lattice ready for simulation
lattice.initialize();
}
}
void prepareLattice(LBconverter<T> const& converter,
BlockStructure2D<T, DESCRIPTOR>& lattice,
Dynamics<T, DESCRIPTOR>& bulkDynamics,
OnLatticeBoundaryCondition2D<T,DESCRIPTOR>& boundaryCondition ) {
int nx = lattice.getNx();
int ny = lattice.getNy();
T omega = converter.getOmega();
/// define lattice Dynamics
lattice.defineDynamics(0,nx-1, 0,ny-1, &bulkDynamics);
/// sets boundary
boundaryCondition.addVelocityBoundary1P(1,nx-2,ny-1,ny-1, omega);
boundaryCondition.addVelocityBoundary1N(1,nx-2, 0, 0, omega);
/// set Velocity
boundaryCondition.addExternalVelocityCornerNN(0,0, omega);
boundaryCondition.addExternalVelocityCornerNP(0,ny-1, omega);
boundaryCondition.addExternalVelocityCornerPN(nx-1,0, omega);
boundaryCondition.addExternalVelocityCornerPP(nx-1,ny-1, omega);
}
void iniGeometry( BlockStructure2D<T, DESCRIPTOR>& latticeOne,
BlockStructure2D<T, DESCRIPTOR>& latticeTwo,
Dynamics<T, DESCRIPTOR>& bulkDynamics1,
Dynamics<T, DESCRIPTOR>& bulkDynamics2,
Dynamics<T, DESCRIPTOR>& bounceBackRho0,
Dynamics<T, DESCRIPTOR>& bounceBackRho1,
T force
)
{
// The setup is: periodicity along horizontal direction, bounce-back on top
// and bottom. The upper half is initially filled with fluid 1 + random noise,
// and the lower half with fluid 2. Only fluid 1 experiences a forces,
// directed downwards.
T noise = 1.e-2;
int nx = latticeOne.getNx();
int ny = latticeOne.getNy();
latticeOne.defineDynamics(0,nx-1, 0,ny-1, &bulkDynamics1);
latticeTwo.defineDynamics(0,nx-1, 0,ny-1, &bulkDynamics2);
latticeOne.defineDynamics(0,nx-1, 0,0, &bounceBackRho0);
latticeTwo.defineDynamics(0,nx-1, 0,0, &bounceBackRho1);
latticeOne.defineDynamics(0,nx-1, ny-1,ny-1, &bounceBackRho1);
latticeTwo.defineDynamics(0,nx-1, ny-1,ny-1, &bounceBackRho0);
for (int iX=0; iX<nx; ++iX) {
for (int iY=0; iY<ny; ++iY) {
T f[2] = {0.,-force};
T zeroVelocity[2] = {0.,0.};
T noForce[2] = {0.,0.};
T rho1 = (T)1;
T rho2 = (T)1;
if (iY>ny/2) {
rho2 = 0.;
rho1 += (double)random()/(double)RAND_MAX * noise;
rho1 += force*DESCRIPTOR<T>::invCs2* ((T)ny - (T)iY - (T)ny/(T)2);
}
else {
rho1 = 0.;
}
Cell<T,DESCRIPTOR>& cell1 = latticeOne.get(iX,iY);
cell1.defineRhoU(rho1, zeroVelocity);
cell1.iniEquilibrium(rho1, zeroVelocity);
cell1.defineExternalField (
DESCRIPTOR<T>::ExternalField::forceBeginsAt,
DESCRIPTOR<T>::ExternalField::sizeOfForce, f );
Cell<T,DESCRIPTOR>& cell2 = latticeTwo.get(iX,iY);
cell2.defineRhoU(rho2, zeroVelocity);
cell2.iniEquilibrium(rho2, zeroVelocity);
cell2.defineExternalField (
DESCRIPTOR<T>::ExternalField::forceBeginsAt,
DESCRIPTOR<T>::ExternalField::sizeOfForce, noForce );
}
}
latticeOne.initialize();
latticeTwo.initialize();
}
