private static void TestCapacity()
{
var factory = new ThermalElement2DFactory(thickness, new ThermalMaterial(density, specialHeatCoeff, thermalConductivity));
ThermalElement2D element = factory.CreateElement(CellType.Tri3, nodeSet0);
IMatrix M = element.BuildCapacityMatrix();
var expectedM = Matrix.CreateFromArray(new double[, ]
{
{ 2, 1, 1 },
{ 1, 2, 1 },
{ 1, 1, 2 }
});
Assert.True(expectedM.Equals(M, 1e-10));
}
private static void TestConductivity()
{
var factory = new ThermalElement2DFactory(thickness, new ThermalMaterial(density, specialHeatCoeff, thermalConductivity));
ThermalElement2D element = factory.CreateElement(CellType.Tri3, nodeSet0);
IMatrix K = element.BuildConductivityMatrix();
var expectedK = Matrix.CreateFromArray(new double[, ]
{
{ 1.0, -0.5, -0.5 },
{ -0.5, 0.5, 0.0 },
{ -0.5, 0.0, 0.5 }
});
Assert.True(expectedK.Equals(K, 1e-10));
}
private static void TestConductivity()
{
var factory = new ThermalElement2DFactory(thickness, new ThermalMaterial(density, specialHeatCoeff, thermalConductivity, thermalConvection));
ThermalElement2D element = factory.CreateElement(CellType.Quad4, nodeSet0);
IMatrix K = element.BuildDiffusionConductivityMatrix();
var expectedK = Matrix.CreateFromArray(new double[, ]
{
{ 2.0 / 3, -1.0 / 6, -1.0 / 3, -1 / 6.0 },
{ -1 / 6.0, 2.0 / 3, -1.0 / 6, -1.0 / 3 },
{ -1.0 / 3, -1.0 / 6, 2.0 / 3, -1.0 / 6 },
{ -1 / 6.0, -1.0 / 3, -1.0 / 6, 2.0 / 3 }
});
Assert.True(expectedK.Equals(K, 1e-10));
}
private static void AddHostElements(Model model)
{
// Material
double density = 1.0;
double c = 1.0;
double h = 0;
// Generate mesh
var meshGenerator = new UniformMeshGenerator2D <Node>(minX, minY, maxX, maxY, numElementsX, numElementsY);
(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 the elements to the model
var elementFactory = new ThermalElement2DFactory(1.0, new ThermalMaterial(density, c, conductivityMatrix, h));
for (int e = 0; e < cells.Count; ++e)
{
ThermalElement2D element = elementFactory.CreateElement(cells[e].CellType, cells[e].Vertices);
var elementWrapper = new Element()
{
ID = e + hostElementsIDStart, ElementType = element
};
foreach (Node node in element.Nodes)
{
elementWrapper.AddNode(node);
}
model.ElementsDictionary.Add(elementWrapper.ID, elementWrapper);
model.SubdomainsDictionary[subdomainID].Elements.Add(elementWrapper);
}
}
private static Model CreateModel()
{
var model = new Model();
// Subdomains
model.SubdomainsDictionary.Add(0, new Subdomain(subdomainID));
// Material
double density = 1.0;
double k = 1.0;
double c = 1.0;
// Nodes
int numNodes = 9;
var nodes = new Node[numNodes];
nodes[0] = new Node(id: 0, x: 0.0, y: 0.0);
nodes[1] = new Node(id: 1, x: 1.0, y: 0.0);
nodes[2] = new Node(id: 2, x: 2.0, y: 0.0);
nodes[3] = new Node(id: 3, x: 0.0, y: 1.0);
nodes[4] = new Node(id: 4, x: 1.0, y: 1.0);
nodes[5] = new Node(id: 5, x: 2.0, y: 1.0);
nodes[6] = new Node(id: 6, x: 0.0, y: 2.0);
nodes[7] = new Node(id: 7, x: 1.0, y: 2.0);
nodes[8] = new Node(id: 8, x: 2.0, y: 2.0);
for (int i = 0; i < numNodes; ++i)
{
model.NodesDictionary[i] = nodes[i];
}
// Elements
int numElements = 4;
var elementFactory = new ThermalElement2DFactory(1.0, new ThermalMaterial(density, c, k));
var elements = new ThermalElement2D[4];
elements[0] = elementFactory.CreateElement(CellType.Quad4, new Node[] { nodes[0], nodes[1], nodes[4], nodes[3] });
elements[1] = elementFactory.CreateElement(CellType.Quad4, new Node[] { nodes[1], nodes[2], nodes[5], nodes[4] });
elements[2] = elementFactory.CreateElement(CellType.Quad4, new Node[] { nodes[3], nodes[4], nodes[7], nodes[6] });
elements[3] = elementFactory.CreateElement(CellType.Quad4, new Node[] { nodes[4], nodes[5], nodes[8], nodes[7] });
for (int i = 0; i < numElements; ++i)
{
var elementWrapper = new Element()
{
ID = i, ElementType = elements[i]
};
foreach (var node in elements[i].Nodes)
{
elementWrapper.AddNode(node);
}
model.ElementsDictionary[i] = elementWrapper;
model.SubdomainsDictionary[subdomainID].Elements.Add(elementWrapper);
}
// Dirichlet BC
model.NodesDictionary[0].Constraints.Add(new Constraint()
{
DOF = ThermalDof.Temperature, Amount = 100.0
});
model.NodesDictionary[3].Constraints.Add(new Constraint()
{
DOF = ThermalDof.Temperature, Amount = 100.0
});
model.NodesDictionary[6].Constraints.Add(new Constraint()
{
DOF = ThermalDof.Temperature, Amount = 100.0
});
// Neumann BC
double q = 50.0;
model.Loads.Add(new Load()
{
Amount = q / 2.0, Node = model.NodesDictionary[2], DOF = ThermalDof.Temperature
});
model.Loads.Add(new Load()
{
Amount = q, Node = model.NodesDictionary[5], DOF = ThermalDof.Temperature
});
model.Loads.Add(new Load()
{
Amount = q / 2.0, Node = model.NodesDictionary[8], DOF = ThermalDof.Temperature
});
return(model);
}
