mirror of
https://github.com/NGSolve/netgen.git
synced 2024-12-27 06:10:34 +05:00
563 lines
20 KiB
C++
563 lines
20 KiB
C++
#include <mystdlib.h>
|
|
#include "meshing.hpp"
|
|
|
|
namespace netgen
|
|
{
|
|
|
|
void InsertVirtualBoundaryLayer (Mesh & mesh)
|
|
{
|
|
cout << "Insert virt. b.l." << endl;
|
|
|
|
int surfid;
|
|
|
|
cout << "Boundary Nr:";
|
|
cin >> surfid;
|
|
|
|
int i, j;
|
|
int np = mesh.GetNP();
|
|
|
|
cout << "Old NP: " << mesh.GetNP() << endl;
|
|
cout << "Trigs: " << mesh.GetNSE() << endl;
|
|
|
|
BitArray bndnodes(np);
|
|
Array<int> mapto(np);
|
|
|
|
bndnodes.Clear();
|
|
for (i = 1; i <= mesh.GetNSeg(); i++)
|
|
{
|
|
int snr = mesh.LineSegment(i).edgenr;
|
|
cout << "snr = " << snr << endl;
|
|
if (snr == surfid)
|
|
{
|
|
bndnodes.Set (mesh.LineSegment(i)[0]);
|
|
bndnodes.Set (mesh.LineSegment(i)[1]);
|
|
}
|
|
}
|
|
for (i = 1; i <= mesh.GetNSeg(); i++)
|
|
{
|
|
int snr = mesh.LineSegment(i).edgenr;
|
|
if (snr != surfid)
|
|
{
|
|
bndnodes.Clear (mesh.LineSegment(i)[0]);
|
|
bndnodes.Clear (mesh.LineSegment(i)[1]);
|
|
}
|
|
}
|
|
|
|
for (i = 1; i <= np; i++)
|
|
{
|
|
if (bndnodes.Test(i))
|
|
mapto.Elem(i) = mesh.AddPoint (mesh.Point (i));
|
|
else
|
|
mapto.Elem(i) = 0;
|
|
}
|
|
|
|
for (i = 1; i <= mesh.GetNSE(); i++)
|
|
{
|
|
Element2d & el = mesh.SurfaceElement(i);
|
|
for (j = 1; j <= el.GetNP(); j++)
|
|
if (mapto.Get(el.PNum(j)))
|
|
el.PNum(j) = mapto.Get(el.PNum(j));
|
|
}
|
|
|
|
|
|
int nq = 0;
|
|
for (i = 1; i <= mesh.GetNSeg(); i++)
|
|
{
|
|
int snr = mesh.LineSegment(i).edgenr;
|
|
if (snr == surfid)
|
|
{
|
|
int p1 = mesh.LineSegment(i)[0];
|
|
int p2 = mesh.LineSegment(i)[1];
|
|
int p3 = mapto.Get (p1);
|
|
if (!p3) p3 = p1;
|
|
int p4 = mapto.Get (p2);
|
|
if (!p4) p4 = p2;
|
|
|
|
Element2d el(QUAD);
|
|
el.PNum(1) = p1;
|
|
el.PNum(2) = p2;
|
|
el.PNum(3) = p3;
|
|
el.PNum(4) = p4;
|
|
el.SetIndex (2);
|
|
mesh.AddSurfaceElement (el);
|
|
nq++;
|
|
}
|
|
}
|
|
|
|
cout << "New NP: " << mesh.GetNP() << endl;
|
|
cout << "Quads: " << nq << endl;
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
Philippose Rajan - 11 June 2009
|
|
|
|
Function to calculate the surface normal at a given
|
|
vertex of a surface element, with respect to that
|
|
surface element.
|
|
|
|
This function is used by the boundary layer generation
|
|
function, in order to calculate the effective direction
|
|
in which the prismatic layer should grow
|
|
*/
|
|
void GetSurfaceNormal(Mesh & mesh, Element2d & el, int Vertex, Vec3d & SurfaceNormal)
|
|
{
|
|
int Vertex_A;
|
|
int Vertex_B;
|
|
|
|
Vertex_A = Vertex + 1;
|
|
if(Vertex_A > el.GetNP()) Vertex_A = 1;
|
|
|
|
Vertex_B = Vertex - 1;
|
|
if(Vertex_B <= 0) Vertex_B = el.GetNP();
|
|
|
|
Vec3d Vect_A,Vect_B;
|
|
|
|
Vect_A = mesh.Point(el.PNum(Vertex_A)) - mesh.Point(el.PNum(Vertex));
|
|
Vect_B = mesh.Point(el.PNum(Vertex_B)) - mesh.Point(el.PNum(Vertex));
|
|
|
|
SurfaceNormal = Cross(Vect_A,Vect_B);
|
|
SurfaceNormal.Normalize();
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
Philippose Rajan - 11 June 2009
|
|
|
|
Added an initial experimental function for
|
|
generating prismatic boundary layers on
|
|
a given set of surfaces.
|
|
|
|
The number of layers, height of the first layer
|
|
and the growth / shrink factor can be specified
|
|
by the user
|
|
|
|
Currently, the layer height is calculated using:
|
|
height = h_first_layer * (growth_factor^(num_layers - 1))
|
|
*/
|
|
void GenerateBoundaryLayer (Mesh & mesh)
|
|
{
|
|
int i, j;
|
|
|
|
cout << "Generate Prismatic Boundary Layers (Experimental)...." << endl;
|
|
|
|
// Use an array to support creation of boundary
|
|
// layers for multiple surfaces in the future...
|
|
Array<int> surfid;
|
|
int surfinp = 0;
|
|
int prismlayers = 1;
|
|
double hfirst = 0.01;
|
|
double growthfactor = 1.0;
|
|
|
|
// Monitor and print out the number of prism and quad elements
|
|
// added to the mesh
|
|
int numprisms = 0;
|
|
int numquads = 0;
|
|
|
|
while(surfinp >= 0)
|
|
{
|
|
cout << "Enter Surface ID (-1 to end list): ";
|
|
cin >> surfinp;
|
|
if(surfinp >= 0) surfid.Append(surfinp);
|
|
}
|
|
|
|
cout << "Number of surfaces entered = " << surfid.Size() << endl;
|
|
|
|
cout << endl << "Enter number of prism layers: ";
|
|
cin >> prismlayers;
|
|
if(prismlayers < 1) prismlayers = 1;
|
|
|
|
cout << "Enter height of first layer: ";
|
|
cin >> hfirst;
|
|
if(hfirst <= 0.0) hfirst = 0.01;
|
|
|
|
cout << "Enter layer growth / shrink factor: ";
|
|
cin >> growthfactor;
|
|
if(growthfactor <= 0.0) growthfactor = 1.0;
|
|
|
|
cout << "Old NP: " << mesh.GetNP() << endl;
|
|
cout << "Old NSE: " << mesh.GetNSE() << endl;
|
|
|
|
for(int layer = prismlayers; layer >= 1; layer--)
|
|
{
|
|
cout << "Generating layer: " << layer << endl;
|
|
|
|
//double layerht = hfirst + growthfactor*(layer - 1)*hfirst;
|
|
double layerht = hfirst*pow(growthfactor,(double)(layer-1));
|
|
|
|
// Need to store the old number of points and
|
|
// surface elements because there are new points and
|
|
// surface elements being added during the process
|
|
int np = mesh.GetNP();
|
|
int nse = mesh.GetNSE();
|
|
|
|
// Safety measure to ensure no issues with mesh
|
|
// consistency
|
|
int nseg = mesh.GetNSeg();
|
|
|
|
const MeshTopology& meshtopo = mesh.GetTopology();
|
|
|
|
// Indicate which points need to be remapped
|
|
BitArray bndnodes(np);
|
|
|
|
// Map of the old points to the new points
|
|
Array<int> mapto(np);
|
|
|
|
// Growth vectors for the prismatic layer based on
|
|
// the effective surface normal at a given point
|
|
Array<Vec3d> growthvectors(np);
|
|
|
|
// Update the mesh topology structures
|
|
mesh.UpdateTopology();
|
|
|
|
// Bit array to identify all the points belonging
|
|
// to the surface of interest
|
|
bndnodes.Clear();
|
|
|
|
// Run through all the surface elements and mark the points
|
|
// belonging to those where a boundary layer has to be created.
|
|
// In addition, also calculate the effective surface normal
|
|
// vectors at each of those points to determine the mesh motion
|
|
// direction
|
|
cout << "Marking points for remapping...." << endl;
|
|
|
|
for (i = 1; i <= nse; i++)
|
|
{
|
|
int snr = mesh.SurfaceElement(i).GetIndex();
|
|
// cout << "snr = " << snr << endl;
|
|
if (surfid.Contains(snr))
|
|
{
|
|
Element2d & sel = mesh.SurfaceElement(i);
|
|
int selNP = sel.GetNP();
|
|
for(j = 1; j <= selNP; j++)
|
|
{
|
|
// Set the bitarray to indicate that the
|
|
// point is part of the required set
|
|
bndnodes.Set(sel.PNum(j));
|
|
|
|
// Vec3d& surfacenormal = Vec3d(); ????
|
|
Vec3d surfacenormal;
|
|
|
|
// Calculate the surface normal at the current point
|
|
// with respect to the current surface element
|
|
GetSurfaceNormal(mesh,sel,j,surfacenormal);
|
|
|
|
// Add the surface normal to the already existent one
|
|
// (This gives the effective normal direction at corners
|
|
// and curved areas)
|
|
growthvectors.Elem(sel.PNum(j)) = growthvectors.Elem(sel.PNum(j))
|
|
+ surfacenormal;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add additional points into the mesh structure in order to
|
|
// clone the surface elements.
|
|
// Also invert the growth vectors so that they point inwards,
|
|
// and normalize them
|
|
cout << "Cloning points and calculating growth vectors...." << endl;
|
|
|
|
for (i = 1; i <= np; i++)
|
|
{
|
|
if (bndnodes.Test(i))
|
|
{
|
|
mapto.Elem(i) = mesh.AddPoint (mesh.Point (i));
|
|
|
|
growthvectors.Elem(i).Normalize();
|
|
growthvectors.Elem(i) *= -1.0;
|
|
}
|
|
else
|
|
{
|
|
mapto.Elem(i) = 0;
|
|
}
|
|
}
|
|
|
|
|
|
// Add quad surface elements at edges for surfaces which
|
|
// dont have boundary layers
|
|
|
|
// Bit array to keep track of segments already processed
|
|
BitArray segsel(nseg);
|
|
|
|
// Set them all to "1" to initially activate all segments
|
|
segsel.Set();
|
|
|
|
cout << "Adding 2D Quad elements on required surfaces...." << endl;
|
|
|
|
for (i = 1; i <= nseg; i++)
|
|
{
|
|
int seg_p1 = mesh.LineSegment(i)[0];
|
|
int seg_p2 = mesh.LineSegment(i)[1];
|
|
|
|
// Only go in if the segment is still active, and if both its
|
|
// surface index is part of the "hit-list"
|
|
if(segsel.Test(i) && surfid.Contains(mesh.LineSegment(i).si))
|
|
{
|
|
// clear the bit to indicate that this segment has been processed
|
|
segsel.Clear(i);
|
|
|
|
// Find matching segment pair on other surface
|
|
for(j = 1; j <= nseg; j++)
|
|
{
|
|
int segpair_p1 = mesh.LineSegment(j)[1];
|
|
int segpair_p2 = mesh.LineSegment(j)[0];
|
|
|
|
// Find the segment pair on the neighbouring surface element
|
|
// Identified by: seg1[0] = seg_pair[1] and seg1[1] = seg_pair[0]
|
|
if(segsel.Test(j) && ((segpair_p1 == seg_p1) && (segpair_p2 == seg_p2)))
|
|
{
|
|
// clear bit to indicate that processing of this segment is done
|
|
segsel.Clear(j);
|
|
|
|
// Only worry about those surfaces which are not in the
|
|
// boundary layer list
|
|
if(!surfid.Contains(mesh.LineSegment(j).si))
|
|
{
|
|
int pnt_commelem = 0;
|
|
int pnum_commelem = 0;
|
|
Array<int> pnt1_elems;
|
|
Array<int> pnt2_elems;
|
|
|
|
|
|
meshtopo.GetVertexSurfaceElements(segpair_p1,pnt1_elems);
|
|
meshtopo.GetVertexSurfaceElements(segpair_p2,pnt2_elems);
|
|
for(int k = 1; k <= pnt1_elems.Size(); k++)
|
|
{
|
|
Element2d pnt1_sel = mesh.SurfaceElement(pnt1_elems.Elem(k));
|
|
for(int l = 1; l <= pnt2_elems.Size(); l++)
|
|
{
|
|
Element2d pnt2_sel = mesh.SurfaceElement(pnt2_elems.Elem(l));
|
|
if((pnt1_sel.GetIndex() == mesh.LineSegment(j).si)
|
|
&& (pnt2_sel.GetIndex() == mesh.LineSegment(j).si)
|
|
&& (pnt1_elems.Elem(k) == pnt2_elems.Elem(l)))
|
|
{
|
|
pnt_commelem = pnt1_elems.Elem(k);
|
|
}
|
|
}
|
|
}
|
|
|
|
for(int k = 1; k <= mesh.SurfaceElement(pnt_commelem).GetNP(); k++)
|
|
{
|
|
if((mesh.SurfaceElement(pnt_commelem).PNum(k) != segpair_p1)
|
|
&& (mesh.SurfaceElement(pnt_commelem).PNum(k) != segpair_p2))
|
|
{
|
|
pnum_commelem = mesh.SurfaceElement(pnt_commelem).PNum(k);
|
|
}
|
|
}
|
|
|
|
Vec3d surfelem_vect1, surfelem_vect2, surfelem_vect;
|
|
|
|
surfelem_vect1 = mesh.Point(pnum_commelem) - mesh.Point(segpair_p1);
|
|
surfelem_vect2 = mesh.Point(pnum_commelem) - mesh.Point(segpair_p2);
|
|
surfelem_vect1.Normalize();
|
|
surfelem_vect2.Normalize();
|
|
surfelem_vect = surfelem_vect1 + surfelem_vect2;
|
|
surfelem_vect.Normalize();
|
|
|
|
double surfangle = Angle(growthvectors.Elem(segpair_p1),surfelem_vect);
|
|
|
|
|
|
// remap the segments to the new points
|
|
mesh.LineSegment(i)[0] = mapto.Get(seg_p1);
|
|
mesh.LineSegment(i)[1] = mapto.Get(seg_p2);
|
|
mesh.LineSegment(j)[1] = mapto.Get(seg_p1);
|
|
mesh.LineSegment(j)[0] = mapto.Get(seg_p2);
|
|
|
|
if(surfangle <= 1.5707)
|
|
{
|
|
// Add a quad element to account for the prism volume
|
|
// element which is going to be added
|
|
Element2d sel(QUAD);
|
|
sel.PNum(4) = mapto.Get(seg_p1);
|
|
sel.PNum(3) = mapto.Get(seg_p2);
|
|
sel.PNum(2) = segpair_p2;
|
|
sel.PNum(1) = segpair_p1;
|
|
sel.SetIndex(mesh.LineSegment(j).si);
|
|
mesh.AddSurfaceElement(sel);
|
|
numquads++;
|
|
}
|
|
else
|
|
{
|
|
for (int k = 1; k <= pnt1_elems.Size(); k++)
|
|
{
|
|
Element2d & pnt_sel = mesh.SurfaceElement(pnt1_elems.Elem(k));
|
|
if(pnt_sel.GetIndex() == mesh.LineSegment(j).si)
|
|
{
|
|
for(int l = 1; l <= pnt_sel.GetNP(); l++)
|
|
{
|
|
if(pnt_sel.PNum(l) == segpair_p1)
|
|
{
|
|
pnt_sel.PNum(l) = mapto.Get(seg_p1);
|
|
}
|
|
else if(pnt_sel.PNum(l) == segpair_p2)
|
|
{
|
|
pnt_sel.PNum(l) = mapto.Get(seg_p2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
for (int k = 1; k <= pnt2_elems.Size(); k++)
|
|
{
|
|
Element2d & pnt_sel = mesh.SurfaceElement(pnt2_elems.Elem(k));
|
|
if(pnt_sel.GetIndex() == mesh.LineSegment(j).si)
|
|
{
|
|
for(int l = 1; l <= pnt_sel.GetNP(); l++)
|
|
{
|
|
if(pnt_sel.PNum(l) == segpair_p1)
|
|
{
|
|
pnt_sel.PNum(l) = mapto.Get(seg_p1);
|
|
}
|
|
else if(pnt_sel.PNum(l) == segpair_p2)
|
|
{
|
|
pnt_sel.PNum(l) = mapto.Get(seg_p2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// If the code comes here, it indicates that we are at
|
|
// a line segment pair which is at the intersection
|
|
// of two surfaces, both of which have to grow boundary
|
|
// layers.... here too, remapping the segments to the
|
|
// new points is required
|
|
mesh.LineSegment(i)[0] = mapto.Get(seg_p1);
|
|
mesh.LineSegment(i)[1] = mapto.Get(seg_p2);
|
|
mesh.LineSegment(j)[1] = mapto.Get(seg_p1);
|
|
mesh.LineSegment(j)[0] = mapto.Get(seg_p2);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add prismatic cells at the boundaries
|
|
cout << "Generating prism boundary layer volume elements...." << endl;
|
|
|
|
for (i = 1; i <= nse; i++)
|
|
{
|
|
Element2d & sel = mesh.SurfaceElement(i);
|
|
if(surfid.Contains(sel.GetIndex()))
|
|
{
|
|
Element el(PRISM);
|
|
for (j = 1; j <= sel.GetNP(); j++)
|
|
{
|
|
// Check (Doublecheck) if the corresponding point has a
|
|
// copy available for remapping
|
|
if (mapto.Get(sel.PNum(j)))
|
|
{
|
|
// Define the points of the newly added Prism cell
|
|
el.PNum(j+3) = mapto.Get(sel.PNum(j));
|
|
el.PNum(j) = sel.PNum(j);
|
|
}
|
|
}
|
|
|
|
el.SetIndex(1);
|
|
el.Invert();
|
|
mesh.AddVolumeElement(el);
|
|
numprisms++;
|
|
}
|
|
}
|
|
|
|
// Finally switch the point indices of the surface elements
|
|
// to the newly added ones
|
|
cout << "Transferring boundary layer surface elements to new vertex references...." << endl;
|
|
|
|
for (i = 1; i <= nse; i++)
|
|
{
|
|
Element2d & sel = mesh.SurfaceElement(i);
|
|
if(surfid.Contains(sel.GetIndex()))
|
|
{
|
|
for (j = 1; j <= sel.GetNP(); j++)
|
|
{
|
|
// Check (Doublecheck) if the corresponding point has a
|
|
// copy available for remapping
|
|
if (mapto.Get(sel.PNum(j)))
|
|
{
|
|
// Map the surface elements to the new points
|
|
sel.PNum(j) = mapto.Get(sel.PNum(j));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Lock all the prism points so that the rest of the mesh can be
|
|
// optimised without invalidating the entire mesh
|
|
for (i = 1; i <= np; i++)
|
|
{
|
|
if(bndnodes.Test(i)) mesh.AddLockedPoint(i);
|
|
}
|
|
|
|
// Now, actually pull back the old surface points to create
|
|
// the actual boundary layers
|
|
cout << "Moving and optimising boundary layer points...." << endl;
|
|
|
|
for (i = 1; i <= np; i++)
|
|
{
|
|
Array<int> vertelems;
|
|
|
|
if(bndnodes.Test(i))
|
|
{
|
|
MeshPoint pointtomove;
|
|
|
|
pointtomove = mesh.Point(i);
|
|
|
|
if(layer == prismlayers)
|
|
{
|
|
mesh.Point(i).SetPoint(pointtomove + layerht * growthvectors.Elem(i));
|
|
|
|
meshtopo.GetVertexElements(i,vertelems);
|
|
|
|
for(j = 1; j <= vertelems.Size(); j++)
|
|
{
|
|
double sfact = 0.9;
|
|
Element volel = mesh.VolumeElement(vertelems.Elem(j));
|
|
if((volel.GetType() == TET) || (volel.GetType() == TET10))
|
|
{
|
|
while((volel.Volume(mesh.Points()) <= 0.0) && (sfact >= 0.0))
|
|
{
|
|
mesh.Point(i).SetPoint(pointtomove + (sfact * layerht * growthvectors.Elem(i)));
|
|
mesh.ImproveMesh();
|
|
|
|
// Try to move the point back by one step but
|
|
// if the volume drops to below zero, double back
|
|
mesh.Point(i).SetPoint(pointtomove + ((sfact + 0.1) * layerht * growthvectors.Elem(i)));
|
|
if(volel.Volume(mesh.Points()) <= 0.0)
|
|
{
|
|
mesh.Point(i).SetPoint(pointtomove + (sfact * layerht * growthvectors.Elem(i)));
|
|
}
|
|
sfact -= 0.1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
mesh.Point(i).SetPoint(pointtomove + layerht * growthvectors.Elem(i));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Optimise the tet part of the volume mesh after all the modifications
|
|
// to the system are completed
|
|
//OptimizeVolume(mparam,mesh);
|
|
|
|
cout << "New NP: " << mesh.GetNP() << endl;
|
|
cout << "Num of Quads: " << numquads << endl;
|
|
cout << "Num of Prisms: " << numprisms << endl;
|
|
cout << "Boundary Layer Generation....Done!" << endl;
|
|
}
|
|
|
|
}
|
|
|