/// <summary>
///
/// </summary>
/// <param name="mesh"></param>
/// <param name="crack"></param>
/// <param name="magnificationOfJintegralRadius">The outer countour of the J-integral domain is defined as:
/// radius = magnification * sqrt(areaOfElementContainingTip). This parameter is the magnification.
/// It should be at least 1.5 (see "Modeling quasi-static crack growth with the extended finite element
/// method Part II: Numerical applications, Huang et al, 2003" page 7546). Usually values 2-3 are selected
/// (see Ahmed thesis, 2009).</param>
/// <param name="auxiliaryStatesStrategy"></param>
/// <param name="sifCalculationStrategy"></param>
public Propagator(IMesh2D <XNode, XContinuumElement2D> mesh, double magnificationOfJintegralRadius,
IAuxiliaryStates auxiliaryStatesStrategy, ISIFCalculator sifCalculationStrategy,
ICrackGrowthDirectionLaw2D growthDirectionLaw, ICrackGrowthLengthLaw2D growthLengthLaw)
{
this.mesh = mesh;
this.magnificationOfJintegralRadius = magnificationOfJintegralRadius;
this.auxiliaryStatesStrategy = auxiliaryStatesStrategy;
this.sifCalculationStrategy = sifCalculationStrategy;
this.growthDirectionLaw = growthDirectionLaw;
this.growthLengthLaw = growthLengthLaw;
this.Logger = new PropagationLogger();
}
/// <summary>
/// Given a set of Heaviside enriched nodes, find which of them must not be enriched, in order to avoid the global
/// stiffness matrix being singular.
/// </summary>
/// <param name="mesh"></param>
/// <param name="heavisideNodes">They will not be altered.</param>
/// <returns></returns>
public ISet <XNode> FindHeavisideNodesToRemove(ISingleCrack crack, IMesh2D <XNode, XContinuumElement2D> mesh,
ISet <XNode> heavisideNodes)
{
var processedElements = new Dictionary <XContinuumElement2D, Tuple <double, double> >();
var nodesToRemove = new HashSet <XNode>();
foreach (var node in heavisideNodes)
{
double nodePositiveArea = 0.0;
double nodeNegativeArea = 0.0;
foreach (var element in mesh.FindElementsWithNode(node))
{
bool alreadyProcessed = processedElements.TryGetValue(element, out Tuple <double, double> elementPosNegAreas);
if (!alreadyProcessed)
{
(double elementPosArea, double elementNegArea) = FindSignedAreasOfElement(crack, element);
elementPosNegAreas = new Tuple <double, double>(elementPosArea, elementNegArea);
processedElements[element] = elementPosNegAreas;
}
nodePositiveArea += elementPosNegAreas.Item1;
nodeNegativeArea += elementPosNegAreas.Item2;
}
if (crack.SignedDistanceOf(node) >= 0.0)
{
double negativeAreaRatio = nodeNegativeArea / (nodePositiveArea + nodeNegativeArea);
if (negativeAreaRatio < relativeAreaTolerance)
{
nodesToRemove.Add(node);
}
}
else
{
double positiveAreaRatio = nodePositiveArea / (nodePositiveArea + nodeNegativeArea);
if (positiveAreaRatio < relativeAreaTolerance)
{
nodesToRemove.Add(node);
}
}
}
return(nodesToRemove);
}
public GuidedPartioner2D(IMesh2D <TNode, TElement> mesh, Dictionary <int, IRegion2D> regions)
{
this.mesh = mesh;
this.regions = regions;
}