void Foam::immersedBoundaryFvPatch::makeTriAddressing() const
{
if (debug)
{
InfoIn("void immersedBoundaryFvPatch::makeTriAddressing() const")
<< "creating tri addressing for immersed boundary " << name()
<< endl;
}
// It is an error to attempt to recalculate
// if the pointer is already set
if (cellsToTriAddrPtr_ || cellsToTriWeightsPtr_)
{
FatalErrorIn("immersedBoundaryFvPatch::makeTriAddressing() const")
<< "tri addressing already exist"
<< "for immersed boundary" << name()
<< abort(FatalError);
}
// Get reference to tri patch and hit faces
const triSurface& triPatch = ibPolyPatch_.ibMesh();
const vectorField& triCentres = triPatch.faceCentres();
const labelList& hf = hitFaces();
const vectorField& ibp = ibPoints();
// Create a markup field and mark all tris containing an ib point with its
// index
labelList hitTris(triPatch.size(), -1);
forAll (hf, hfI)
{
hitTris[hf[hfI]] = hfI;
}
// Allocate storage
cellsToTriAddrPtr_ = new labelListList(triPatch.size());
labelListList& addr = *cellsToTriAddrPtr_;
cellsToTriWeightsPtr_ = new scalarListList(triPatch.size());
scalarListList& w = *cellsToTriWeightsPtr_;
// Algorithm:
// For each tri face, check if it contains an IB point
// - if so, set the addressing to the index of IB point and weight to 1
// - if not, search the neighbouring faces of the visited faces until
// at least 3 IB points are found, or the neighbourhood is exhausted.
// When a sufficient number of points is found, calculate the weights
// using inverse distance weighting
// Get addressing from the triangular patch
const labelListList& pf = triPatch.pointFaces();
forAll (triPatch, triI)
{
if (hitTris[triI] > -1)
{
// Triangle contains IB point
addr[triI].setSize(1);
w[triI].setSize(1);
addr[triI] = hitTris[triI];
w[triI] = 1;
}
else
{
// No direct hit. Start a neighbourhood search
// Record already visited faces
labelHashSet visited;
// Collect new faces to visit
SLList<label> nextToVisit;
// Collect IB points for interpolation
labelHashSet ibPointsToUse;
// Initialise with the original tri
nextToVisit.insert(triI);
do
{
const label curTri = nextToVisit.removeHead();
// Discard tri if already visited
if (visited[curTri]) continue;
visited.insert(curTri);
const triFace& curTriPoints = triPatch[curTri];
// For all current points of face, pick up neighbouring faces
forAll (curTriPoints, tpI)
{
const labelList curNbrs = pf[curTriPoints[tpI]];
forAll (curNbrs, nbrI)
{
if (!visited.found(curNbrs[nbrI]))
{
// Found a face which is not visited. Add it to
// the list of faces to visit
nextToVisit.append(curNbrs[nbrI]);
if (hitTris[curNbrs[nbrI]] > -1)
{
// Found a neighbour with a hit: use this
// IB point
ibPointsToUse.insert(hitTris[curNbrs[nbrI]]);
}
}
}
}
} while
(
ibPointsToUse.size() < 3
&& !nextToVisit.empty()
);
// Found neighbourhood: collect addressing and weights
addr[triI] = ibPointsToUse.toc();
w[triI].setSize(addr[triI].size());
labelList& curAddr = addr[triI];
scalarList& curW = w[triI];
vector curTriCentre = triCentres[triI];
scalar sumW = 0;
forAll (curAddr, ibI)
{
curW[ibI] = 1/mag(curTriCentre - ibp[curAddr[ibI]]);
sumW += curW[ibI];
}
// Divide weights by sum distance
forAll (curW, ibI)
{
curW[ibI] /= sumW;
}
}
}
