void Network::getNetForces() {
for (int i = 0; i <= iMax; i++) {
for (int j = 0; j <= jMax; j++) {
isiMax = i == iMax;
isjMin = j == 0;
isjMax = j == jMax;
int j1 = isjMax ? 0 : j + 1;
int i1 = isiMax ? 0 : i + 1;
int j2 = isjMin ? jMax : j - 1;
double tempPos[8] = {
pos[(i * netSize + j) * 2],
pos[(i * netSize + j) * 2 + 1],
pos[(i * netSize + j1) * 2],
pos[(i * netSize + j1) * 2 + 1] ,
pos[(i1 * netSize + j) * 2],
pos[(i1 * netSize + j) * 2 + 1],
pos[(i1 * netSize + j2) * 2],
pos[(i1 * netSize + j2) * 2 + 1]
};
// Calculate the net x and y force on each node. Similar to gradient function.
for (int k = 1; k < 4; k++) {
double x_displacement = tempPos[2 * k] + xshift(k) - tempPos[0];
double y_displacement = tempPos[2 * k + 1] + yshift(k) - tempPos[1];
forces[i][j][2 * k - 2] = spr[i][j][k - 1] * deltaL(tempPos, k)
/ euclDist(tempPos, k) * (x_displacement);
forces[i][j][2 * k - 1] = spr[i][j][k - 1] * deltaL(tempPos, k)
/ euclDist(tempPos, k) * (y_displacement);
}
}
}
}
// Network Function Definitions.
double Network::operator() () {
double funcvalue = 0;
for(int i = 0; i <= iMax; i++) {
for (int j = 0; j <= jMax; j++) {
// Make the array double pos[]. This shall point to the
// positions of the following nodes:
//
// 1. node i, j
// 2. node i, j + 1 (j1)
// 3. node i + 1 (i1), j
// 4. node i + 1, j - 1 (j2)
//
// Make sure to impose the periodic boundary condition here.
// This is done by making a temporary node copy of the
// corresponding mode (using modulo arithemetic).
//
// Strain is obtained by shifting the bonds at the top of the
// network over by an integer number of points in the
// x-direction. When measuring the energy, it only affects the
// topmost row (i = iMax).
isiMax = i == iMax;
isjMax = j == jMax;
isjMin = j == 0;
int j1 = isjMax ? 0 : j + 1;
int i1 = isiMax ? 0 : i + 1;
int j2 = isjMin ? jMax : j - 1;
double tempPos[8] = {
pos[(i * netSize + j) * 2],
pos[(i * netSize + j) * 2 + 1],
pos[(i * netSize + j1) * 2],
pos[(i * netSize + j1) * 2 + 1],
pos[(i1 * netSize + j) * 2],
pos[(i1 * netSize + j) * 2 + 1],
pos[(i1 * netSize + j2) * 2],
pos[(i1 * netSize + j2) * 2 + 1]
};
for (int k = 1; k < 4; k++) {
double delta = deltaL(tempPos, k);
funcvalue = 0.5 * spr[i][j][k - 1] / RESTLEN * delta * delta;
}
} // Cycling all columns in a row
} // Cycling all rows
return funcvalue;
}
// * * * * * * * * * * * * * * * * Member Functions * * * * * * * * * * * * * * * //
void Foam::coherentFlameModel2b::update()
{
Info<<"Updating Sigma Source terms"<<endl;
volVectorField M(fvc::grad(b_));
volScalarField mgb_ = mag(M);
dimensionedScalar dSigma = 1.0e-3*
(b_* (scalar(1.0) - b_) * mgb_)().weightedAverage(rho_.mesh().V())
/((b_ * (scalar(1.0) - b_))().weightedAverage(rho_.mesh().V()) + SMALL)
+ dimensionedScalar("dSig", Sigma_.dimensions(), SMALL);
M /= (max(Sigma_, mgb_) + dSigma);
// volScalarField magM = mag(M);
// M /= Sigma_ + dimensionedScalar("tol", dimless/dimLength, SMALL);
// M /= (magM + dimensionedScalar("tol", dimless/dimLength, SMALL));
volScalarField orientationFactor = scalar(1.0) - (M & M);
orientationFactor.max(0.0);
orientationFactor.min(1.0);
volTensorField A_ = I * (1.0 - orientationFactor / 3.0) - (M * M);
volTensorField gradU(fvc::grad(U_));
volScalarField up(sqrt((2.0/3.0)*turbulence_.k()));
//Efficiency function from the ITNFS model
volScalarField GammaK("GammaK", rho_/rho_);
scalar T1 = min(thermo_.Tu()).value();
scalar T2 = max(thermo_.Tb()).value();
volScalarField deltaL(2.0 * thermo_.alpha() / thermo_.rhou() /
Su_ * pow(T2/T1, 0.7));
volScalarField lt(Clt_ * pow(up, 3) / (turbulence_.epsilon() +
dimensionedScalar("tol",
pow(dimVelocity,2)/dimTime, SMALL)));
volScalarField lRatio(lt / deltaL);
volScalarField uRatio(up / Su_);
volScalarField s = max
(
log10 (lRatio),
scalar(-0.4+SMALL)
);
if(fittedGammaK_){
GammaK = 0.75 * exp(-1.2 / pow(uRatio, 0.3)) * pow(lRatio, 2.0/3.0);
} else {
volScalarField sigma1 = 2.0 / 3.0 *
(1.0 - 0.5 * exp(-pow(uRatio, 1.0/3.0)));
volScalarField r = -exp(-(s+0.4)) / (s+0.4) +
(1.0 - exp(-(s+0.4))) * (sigma1 * s - 0.11);
GammaK = pow(10.0, r);
}
if(quenchingCoeff_ != 0.0){
volScalarField g = (0.7 + 1.0 / s) * exp(-s) +
(1.0 - exp(-s)) * (1.0 + 0.36 * s);
volScalarField x = (log10 (uRatio) - g) / s / 0.04;
volScalarField Pq = 0.5 * (1.0 + tanh (sign(x) * x * x));
GammaK -= quenchingCoeff_ * 1.5 * lRatio / uRatio * log (1.0 / (1.0 - Pq));
}
volScalarField P1 = rho_ * alphaSigma_ * GammaK * turbulence_.epsilon() /
(turbulence_.k() + dimensionedScalar("tol", pow(dimVelocity,2), SMALL));
volScalarField P2 = rho_ * (A_ && gradU);
ProdRateForSigma_ = P1 + P2;
DestrRateForSigma_ = rho_ * betaSigma_ *
(Su_ + CSigma_ * sqrt(3.0/2.0) * up) * Sigma_/(b_ * (1.0 - b_) + SMALL);
}
