implementation of closed 1D and 2D cases

This commit is contained in:
philippun 2023-08-11 12:19:33 +02:00
parent 4108038a62
commit f1b5138bcc
2 changed files with 195 additions and 52 deletions

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@ -35,10 +35,14 @@ int main(int argc, char *argv[]) {
// create a boundary with constant values
Boundary bc = Boundary(grid);
bc.setBoundarySideConstant(BC_SIDE_LEFT, 0);
bc.setBoundarySideConstant(BC_SIDE_RIGHT, 0);
bc.setBoundarySideConstant(BC_SIDE_TOP, 0);
bc.setBoundarySideConstant(BC_SIDE_BOTTOM, 0);
bc.setBoundarySideClosed(BC_SIDE_LEFT);
bc.setBoundarySideClosed(BC_SIDE_RIGHT);
bc.setBoundarySideClosed(BC_SIDE_TOP);
bc.setBoundarySideClosed(BC_SIDE_BOTTOM);
// bc.setBoundarySideConstant(BC_SIDE_LEFT, 0);
// bc.setBoundarySideConstant(BC_SIDE_RIGHT, 0);
// bc.setBoundarySideConstant(BC_SIDE_TOP, 0);
// bc.setBoundarySideConstant(BC_SIDE_BOTTOM, 0);
// (optional) set boundary condition values for one side, e.g.:

View File

@ -4,16 +4,71 @@
using namespace Eigen;
static SparseMatrix<double> createCoeffMatrix(MatrixXd &alpha, int numCols, int rowIndex, double sx) {
static tuple<double, double> calcLeftBoundaryCoeffConstant(MatrixXd &alpha, int &rowIndex, double &sx) {
double centerCoeff;
double rightCoeff;
centerCoeff = 1 + sx * (calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1))
+ 2 * alpha(rowIndex,0));
rightCoeff = -sx * calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1));
return {centerCoeff, rightCoeff};
}
static tuple<double, double> calcLeftBoundaryCoeffClosed(MatrixXd &alpha, int &rowIndex, double &sx) {
double centerCoeff;
double rightCoeff;
centerCoeff = 1 + sx * calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1));
rightCoeff = -sx * calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1));
return {centerCoeff, rightCoeff};
}
static tuple<double, double> calcRightBoundaryCoeffConstant(MatrixXd &alpha, int &rowIndex, int &n, double &sx) {
double leftCoeff;
double centerCoeff;
leftCoeff = -sx * calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n));
centerCoeff = 1 + sx * (calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n))
+ 2 * alpha(rowIndex,n));
return {leftCoeff, centerCoeff};
}
static tuple<double, double> calcRightBoundaryCoeffClosed(MatrixXd &alpha, int &rowIndex, int &n, double &sx) {
double leftCoeff;
double centerCoeff;
leftCoeff = -sx * calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n));
centerCoeff = 1 + sx * calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n));
return {leftCoeff, centerCoeff};
}
static SparseMatrix<double> createCoeffMatrix(MatrixXd &alpha, vector<BoundaryElement> bcLeft, vector<BoundaryElement> bcRight, int numCols, int rowIndex, double sx) {
// square matrix of column^2 dimension for the coefficients
SparseMatrix<double> cm(numCols, numCols);
cm.reserve(VectorXi::Constant(numCols, 3));
// left column
cm.insert(0,0) = 1 + sx * (calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1))
+ 2 * alpha(rowIndex,0));
cm.insert(0,1) = -sx * calcAlphaIntercell(alpha(rowIndex,0), alpha(rowIndex,1));
BC_TYPE type = bcLeft[rowIndex].getType();
if (type == BC_TYPE_CONSTANT) {
auto [centerCoeffTop, rightCoeffTop] = calcLeftBoundaryCoeffConstant(alpha, rowIndex, sx);
cm.insert(0,0) = centerCoeffTop;
cm.insert(0,1) = rightCoeffTop;
} else if (type == BC_TYPE_CLOSED) {
auto [centerCoeffTop, rightCoeffTop] = calcLeftBoundaryCoeffClosed(alpha, rowIndex, sx);
cm.insert(0,0) = centerCoeffTop;
cm.insert(0,1) = rightCoeffTop;
} else {
throw_invalid_argument("Undefined Boundary Condition Type somewhere on Left or Top!");
}
// inner columns
int n = numCols-1;
@ -28,22 +83,101 @@ static SparseMatrix<double> createCoeffMatrix(MatrixXd &alpha, int numCols, int
}
// right column
cm.insert(n,n-1) = -sx * calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n));
cm.insert(n,n) = 1 + sx * (calcAlphaIntercell(alpha(rowIndex,n-1), alpha(rowIndex,n))
+ 2 * alpha(rowIndex,n));
type = bcRight[rowIndex].getType();
if (type == BC_TYPE_CONSTANT) {
auto [leftCoeffBottom, centerCoeffBottom] = calcRightBoundaryCoeffConstant(alpha, rowIndex, n, sx);
cm.insert(n,n-1) = leftCoeffBottom;
cm.insert(n,n) = centerCoeffBottom;
} else if (type == BC_TYPE_CLOSED) {
auto [leftCoeffBottom, centerCoeffBottom] = calcRightBoundaryCoeffClosed(alpha, rowIndex, n, sx);
cm.insert(n,n-1) = leftCoeffBottom;
cm.insert(n,n) = centerCoeffBottom;
} else {
throw_invalid_argument("Undefined Boundary Condition Type somewhere on Right or Bottom!");
}
cm.makeCompressed();
cm.makeCompressed(); // important for Eigen solver
return cm;
}
static double calcExplicitConcentrationsTopBoundaryConstant(MatrixXd &concentrations,
MatrixXd &alpha, vector<BoundaryElement> &bcTop, int &rowIndex, int &i, double &sy) {
double c;
c = sy * calcAlphaIntercell(alpha(rowIndex,i), alpha(rowIndex+1,i))
* concentrations(rowIndex,i)
+ (
1 - sy * (
calcAlphaIntercell(alpha(rowIndex,i), alpha(rowIndex+1,i))
+ 2 * alpha(rowIndex,i)
)
) * concentrations(rowIndex,i)
+ sy * alpha(rowIndex,i) * bcTop[i].getValue();
return c;
}
static double calcExplicitConcentrationsTopBoundaryClosed(MatrixXd &concentrations,
MatrixXd &alpha, int &rowIndex, int &i, double &sy) {
double c;
c = sy * calcAlphaIntercell(alpha(rowIndex,i), alpha(rowIndex+1,i))
* concentrations(rowIndex,i)
+ (
1 - sy * (
calcAlphaIntercell(alpha(rowIndex,i), alpha(rowIndex+1,i))
)
) * concentrations(rowIndex,i);
return c;
}
static double calcExplicitConcentrationsBottomBoundaryConstant(MatrixXd &concentrations,
MatrixXd &alpha, vector<BoundaryElement> &bcBottom, int &rowIndex, int &i, double &sy) {
double c;
c = sy * alpha(rowIndex,i) * bcBottom[i].getValue()
+ (
1 - sy * (
2 * alpha(rowIndex,i)
+ calcAlphaIntercell(alpha(rowIndex-1,i), alpha(rowIndex,i))
)
) * concentrations(rowIndex,i)
+ sy * calcAlphaIntercell(alpha(rowIndex-1,i), alpha(rowIndex,i))
* concentrations(rowIndex-1,i);
return c;
}
static double calcExplicitConcentrationsBottomBoundaryClosed(MatrixXd &concentrations,
MatrixXd &alpha, int &rowIndex, int &i, double &sy) {
double c;
c = (
1 - sy * (
+ calcAlphaIntercell(alpha(rowIndex-1,i), alpha(rowIndex,i))
)
) * concentrations(rowIndex,i)
+ sy * calcAlphaIntercell(alpha(rowIndex-1,i), alpha(rowIndex,i))
* concentrations(rowIndex-1,i);
return c;
}
static VectorXd createSolutionVector(MatrixXd &concentrations, MatrixXd &alphaX, MatrixXd &alphaY,
VectorXd &bcLeft, VectorXd &bcRight, VectorXd &bcTop,
VectorXd &bcBottom, int length, int rowIndex, double sx, double sy) {
vector<BoundaryElement> &bcLeft, vector<BoundaryElement> &bcRight,
vector<BoundaryElement> &bcTop, vector<BoundaryElement> &bcBottom,
int length, int rowIndex, double sx, double sy) {
VectorXd sv(length);
int numRows = concentrations.rows();
BC_TYPE type;
// inner rows
if (rowIndex > 0 && rowIndex < numRows-1) {
@ -65,40 +199,40 @@ static VectorXd createSolutionVector(MatrixXd &concentrations, MatrixXd &alphaX,
// first row
if (rowIndex == 0) {
for (int i = 0; i < length; i++) {
sv(i) = sy * calcAlphaIntercell(alphaY(rowIndex,i), alphaY(rowIndex+1,i))
* concentrations(rowIndex,i)
+ (
1 - sy * (
calcAlphaIntercell(alphaY(rowIndex,i), alphaY(rowIndex+1,i))
+ 2 * alphaY(rowIndex,i)
)
) * concentrations(rowIndex,i)
+ sy * alphaY(rowIndex,i) * bcTop(i)
;
type = bcTop[i].getType();
if (type == BC_TYPE_CONSTANT) {
sv(i) = calcExplicitConcentrationsTopBoundaryConstant(concentrations, alphaY, bcTop, rowIndex, i, sy);
} else if (type == BC_TYPE_CLOSED) {
sv(i) = calcExplicitConcentrationsTopBoundaryClosed(concentrations, alphaY, rowIndex, i, sy);
} else {
throw_invalid_argument("Undefined Boundary Condition Type somewhere on Left or Top!");
}
}
}
// last row
if (rowIndex == numRows-1) {
for (int i = 0; i < length; i++) {
sv(i) = sy * alphaY(rowIndex,i) * bcBottom(i)
+ (
1 - sy * (
2 * alphaY(rowIndex,i)
+ calcAlphaIntercell(alphaY(rowIndex-1,i), alphaY(rowIndex,i))
)
) * concentrations(rowIndex,i)
+ sy * calcAlphaIntercell(alphaY(rowIndex-1,i), alphaY(rowIndex,i))
* concentrations(rowIndex-1,i)
;
type = bcBottom[i].getType();
if (type == BC_TYPE_CONSTANT) {
sv(i) = calcExplicitConcentrationsBottomBoundaryConstant(concentrations, alphaY, bcBottom, rowIndex, i, sy);
} else if (type == BC_TYPE_CLOSED) {
sv(i) = calcExplicitConcentrationsBottomBoundaryClosed(concentrations, alphaY, rowIndex, i, sy);
} else {
throw_invalid_argument("Undefined Boundary Condition Type somewhere on Right or Bottom!");
}
}
}
// first column -> additional fixed concentration change from perpendicular dimension
sv(0) += 2 * sx * alphaX(rowIndex,0) * bcLeft(rowIndex);
// first column -> additional fixed concentration change from perpendicular dimension in constant bc case
if (bcLeft[rowIndex].getType() == BC_TYPE_CONSTANT) {
sv(0) += 2 * sx * alphaX(rowIndex,0) * bcLeft[rowIndex].getValue();
}
// last column -> additional fixed concentration change from perpendicular dimension
sv(length-1) += 2 * sx * alphaX(rowIndex,length-1) * bcRight(rowIndex);
// last column -> additional fixed concentration change from perpendicular dimension in constant bc case
if (bcRight[rowIndex].getType() == BC_TYPE_CONSTANT) {
sv(length-1) += 2 * sx * alphaX(rowIndex,length-1) * bcRight[rowIndex].getValue();
}
return sv;
}
@ -124,16 +258,20 @@ static void BTCS_1D(Grid &grid, Boundary &bc, double &timestep) {
VectorXd b(length);
MatrixXd alpha = grid.getAlpha();
VectorXd bcLeft = bc.getBoundarySideValues(BC_SIDE_LEFT);
VectorXd bcRight = bc.getBoundarySideValues(BC_SIDE_RIGHT);
vector<BoundaryElement> bcLeft = bc.getBoundarySide(BC_SIDE_LEFT);
vector<BoundaryElement> bcRight = bc.getBoundarySide(BC_SIDE_RIGHT);
MatrixXd concentrations = grid.getConcentrations();
A = createCoeffMatrix(alpha, length, 0, sx); // this is exactly same as in 2D
A = createCoeffMatrix(alpha, bcLeft, bcRight, length, 0, sx); // this is exactly same as in 2D
for (int i = 0; i < length; i++) {
b(i) = concentrations(0,i); // TODO check if this is really the only thing on right hand side of equation in 1D?
b(i) = concentrations(0,i);
}
if (bc.getBoundaryElementType(BC_SIDE_LEFT, 0) == BC_TYPE_CONSTANT) {
b(0) += 2 * sx * alpha(0,0) * bcLeft[0].getValue();
}
if (bc.getBoundaryElementType(BC_SIDE_RIGHT, 0) == BC_TYPE_CONSTANT) {
b(length-1) += 2 * sx * alpha(0,length-1) * bcRight[0].getValue();
}
b(0) += 2 * sx * alpha(0,0) * bcLeft(0);
b(length-1) += 2 * sx * alpha(0,length-1) * bcRight(0);
concentrations_t1 = solve(A, b);
@ -160,21 +298,21 @@ static void BTCS_2D(Grid &grid, Boundary &bc, double &timestep) {
MatrixXd alphaX = grid.getAlphaX();
MatrixXd alphaY = grid.getAlphaY();
VectorXd bcLeft = bc.getBoundarySideValues(BC_SIDE_LEFT);
VectorXd bcRight = bc.getBoundarySideValues(BC_SIDE_RIGHT);
VectorXd bcTop = bc.getBoundarySideValues(BC_SIDE_TOP);
VectorXd bcBottom = bc.getBoundarySideValues(BC_SIDE_BOTTOM);
vector<BoundaryElement> bcLeft = bc.getBoundarySide(BC_SIDE_LEFT);
vector<BoundaryElement> bcRight = bc.getBoundarySide(BC_SIDE_RIGHT);
vector<BoundaryElement> bcTop = bc.getBoundarySide(BC_SIDE_TOP);
vector<BoundaryElement> bcBottom = bc.getBoundarySide(BC_SIDE_BOTTOM);
MatrixXd concentrations = grid.getConcentrations();
for (int i = 0; i < rowMax; i++) {
A = createCoeffMatrix(alphaX, colMax, i, sx);
A = createCoeffMatrix(alphaX, bcLeft, bcRight, colMax, i, sx);
b = createSolutionVector(concentrations, alphaX, alphaY, bcLeft, bcRight,
bcTop, bcBottom, colMax, i, sx, sy);
row_t1 = solve(A, b);
for (int j = 0; j < colMax; j++) {
concentrations_t1(i,j) = row_t1(j);
concentrations_t1(i,j) = row_t1(j); // TODO Eigen seq ??
}
}
@ -184,13 +322,14 @@ static void BTCS_2D(Grid &grid, Boundary &bc, double &timestep) {
alphaY.transposeInPlace();
for (int i = 0; i < colMax; i++) {
A = createCoeffMatrix(alphaY, rowMax, i, sy);
// swap alphas, boundary conditions and sx/sy for column-wise calculation
A = createCoeffMatrix(alphaY, bcLeft, bcRight, rowMax, i, sy);
b = createSolutionVector(concentrations_t1, alphaY, alphaX, bcTop, bcBottom,
bcLeft, bcRight, rowMax, i, sy, sx);
row_t1 = solve(A, b);
for (int j = 0; j < rowMax; j++) {
concentrations(i,j) = row_t1(j);
concentrations(i,j) = row_t1(j); // TODO Eigen seq ??
}
}
concentrations.transposeInPlace();