public CrackTipEnrichments2D(ISingleCrack crackDescription, CrackTipPosition tipPosition) :
this(crackDescription, tipPosition, new ITipFunction[]
{
new IsotropicBrittleTipFunctions2D.Func1(),
new IsotropicBrittleTipFunctions2D.Func2(),
new IsotropicBrittleTipFunctions2D.Func3(),
new IsotropicBrittleTipFunctions2D.Func4()
})
{
}
// TODO: remove this
public IReadOnlyList <XContinuumElement2D> GetTipElements(CrackTipPosition tipPosition)
{
if (tipPosition == CrackTipPosition.Single)
{
return(tipElements);
}
else
{
throw new ArgumentException("Only works for single tip cracks.");
}
}
// TODO: remove this
public TipCoordinateSystem GetTipSystem(CrackTipPosition tip)
{
if (tip == CrackTipPosition.Single)
{
return(tipSystem);
}
else
{
throw new ArgumentException("Only works for single tip cracks.");
}
}
// TODO: remove this
public CartesianPoint GetCrackTip(CrackTipPosition tipPosition)
{
if (tipPosition == CrackTipPosition.Single)
{
return(crackTip);
}
else
{
throw new ArgumentException("Only works for single tip cracks.");
}
}
public TipCoordinateSystem GetTipSystem(CrackTipPosition tipPosition)
{
if (tipPosition == CrackTipPosition.Start)
{
return(startTipSystem);
}
else if (tipPosition == CrackTipPosition.End)
{
return(endTipSystem);
}
else
{
throw new ArgumentException("Invalid tip position");
}
}
public CartesianPoint GetCrackTip(CrackTipPosition tipPosition)
{
if (tipPosition == CrackTipPosition.Start)
{
return(Vertices.First.Value);
}
else if (tipPosition == CrackTipPosition.End)
{
return(Vertices.Last.Value);
}
else
{
throw new ArgumentException("Invalid tip position");
}
}
public IReadOnlyList <XContinuumElement2D> GetTipElements(CrackTipPosition tipPosition)
{
if (tipPosition == CrackTipPosition.Start)
{
return(startTipElements);
}
else if (tipPosition == CrackTipPosition.End)
{
return(endTipElements);
}
else
{
throw new ArgumentException("Invalid tip position");
}
}
public CrackTipEnrichments2D(ISingleCrack crackDescription, CrackTipPosition tipPosition,
IReadOnlyList <ITipFunction> enrichmentFunctions)
{
this.crackDescription = crackDescription;
this.tipPosition = tipPosition;
this.enrichmentFunctions = enrichmentFunctions;
this.Dofs = new EnrichedDof[]
{
new EnrichedDof(enrichmentFunctions[0], StructuralDof.TranslationX),
new EnrichedDof(enrichmentFunctions[0], StructuralDof.TranslationY),
new EnrichedDof(enrichmentFunctions[1], StructuralDof.TranslationX),
new EnrichedDof(enrichmentFunctions[1], StructuralDof.TranslationY),
new EnrichedDof(enrichmentFunctions[2], StructuralDof.TranslationX),
new EnrichedDof(enrichmentFunctions[2], StructuralDof.TranslationY),
new EnrichedDof(enrichmentFunctions[3], StructuralDof.TranslationX),
new EnrichedDof(enrichmentFunctions[3], StructuralDof.TranslationY),
};
}
private bool IsTipElement(XContinuumElement2D element, CrackTipPosition tipPosition)
{
CartesianPoint crackTip, adjacentVertex;
if (tipPosition == CrackTipPosition.Start)
{
crackTip = Vertices.First.Value;
adjacentVertex = Vertices.First.Next.Value;
}
else if (tipPosition == CrackTipPosition.End)
{
crackTip = Vertices.Last.Value;
adjacentVertex = Vertices.Last.Previous.Value;
}
else
{
throw new ArgumentException("Tip position can be either start or end");
}
var polygon = ConvexPolygon2D.CreateUnsafe(element.Nodes);
PolygonPointPosition relativeTipPos = polygon.FindRelativePositionOfPoint(crackTip);
if (relativeTipPos == PolygonPointPosition.Inside || relativeTipPos == PolygonPointPosition.OnEdge ||
relativeTipPos == PolygonPointPosition.OnVertex)
{
PolygonPointPosition previousVertexPos = polygon.FindRelativePositionOfPoint(adjacentVertex);
if (previousVertexPos == PolygonPointPosition.Inside)
{
throw new NotImplementedException("Problem with blending elements, if the tip element is also " +
"enriched with Heaviside. What happens after the crack tip? Based on the LSM, the signed " +
"distance of the blending element after the crack tip should have a positive and negative " +
"region, however that element is not split by the crack and thus should not have " +
"discontinuity in the displacement field");
//return ElementEnrichmentType.Both;
}
return(true);
}
return(false);
}
