public static void Generate3DMesh()
{
double minX = 0.0, minY = 0.0, minZ = 0.0;
double maxX = 100.0, maxY = 100.0, maxZ = 100.0;
int cellsPerX = 4, cellsPerY = 4, cellsPerZ = 4;
var generator = new UniformMeshGenerator3D <Node>(minX, minY, minZ, maxX, maxY, maxZ, cellsPerX, cellsPerY, cellsPerZ);
generator.StartIDsAt0 = false;
(IReadOnlyList <Node> vertices, IReadOnlyList <CellConnectivity <Node> > cells) =
generator.CreateMesh((id, x, y, z) => new Node(id: id, x: x, y: y, z: z));
Console.WriteLine($"{vertices.Count} vertices:");
foreach (var vertex in vertices)
{
Console.WriteLine($"{vertex.ID} {vertex.X} {vertex.Y} {vertex.Z}");
}
Console.WriteLine();
Console.WriteLine($"{cells.Count} cells:");
int cellID = 1;
string gmshHexa8Tag = "5 2 1 1";
foreach (var cell in cells)
{
Console.Write($"{cellID++} {gmshHexa8Tag} ");
foreach (var vertex in cell.Vertices)
{
Console.Write($"{vertex.ID} ");
}
Console.WriteLine();
}
}
public static void WriteStiffnessOfContinuum3DStructure()
{
// _____ ____
// / / /|
// /____/____/ |
// | | | |
// |____|____|/|
// | | | /
// |____|____|/
//
// Model with 1 subdomain
var model = new Model();
model.SubdomainsDictionary.Add(subdomainID, new Subdomain(subdomainID));
// Material
var material = new ElasticMaterial3D()
{
YoungModulus = 2.1E7,
PoissonRatio = 0.3
};
var dynamicProperties = new DynamicMaterial(1.0, 0.0, 0.0, true);
// Generate mesh
double lengthX = 2.0;
double lengthY = 2.4;
double lengthZ = 2.2;
var meshGenerator = new UniformMeshGenerator3D <Node>(0.0, 0.0, 0.0, lengthX, lengthY, lengthZ, 10, 10, 10);
(IReadOnlyList <Node> vertices, IReadOnlyList <CellConnectivity <Node> > cells) =
meshGenerator.CreateMesh((id, x, y, z) => new Node(id: id, x: x, y: y, z: z));
// Add nodes to the model
for (int n = 0; n < vertices.Count; ++n)
{
model.NodesDictionary.Add(n, vertices[n]);
}
// Add Quad4 elements to the model
var factory = new ContinuumElement3DFactory(material, dynamicProperties);
for (int e = 0; e < cells.Count; ++e)
{
ContinuumElement3D element = factory.CreateElement(cells[e].CellType, cells[e].Vertices);
var elementWrapper = new Element()
{
ID = e, ElementType = element
};
foreach (Node node in element.Nodes)
{
elementWrapper.AddNode(node);
}
model.ElementsDictionary.Add(e, elementWrapper);
model.SubdomainsDictionary[subdomainID].Elements.Add(elementWrapper);
}
// Solver
var solverBuilder = new SkylineSolver.Builder();
SkylineSolver solver = solverBuilder.BuildSolver(model);
// Structural problem provider
var provider = new ProblemStructural(model, solver);
// Linear static analysis
var childAnalyzer = new LinearAnalyzer(model, solver, provider);
var parentAnalyzer = new StaticAnalyzer(model, solver, provider, childAnalyzer);
// Run the analysis to build the stiffness matrix
parentAnalyzer.Initialize();
parentAnalyzer.BuildMatrices();
// Print the stiffness matrix
//var writer = new MatlabWriter();
var writer = new RawArraysWriter();
writer.WriteToMultipleFiles((SkylineMatrix)solver.LinearSystems[subdomainID].Matrix,
outputDirectory + @"\hexa8_10x10x10_stiffness.txt");
}