/// <summary>Computes solution matrix coeffs. for flow control valve.</summary>
private void FcvCoeff(EpanetNetwork net, LsVariables ls, SparseMatrix smat)
{
int k = Index;
double q = setting;
int n1 = smat.GetRow(first.Index);
int n2 = smat.GetRow(second.Index);
// If valve active, break network at valve and treat
// flow setting as external demand at upstream node
// and external supply at downstream node.
if (status == StatType.ACTIVE)
{
ls.AddNodalInFlow(first.Index, -q);
ls.AddRhsCoeff(n1, -q);
ls.AddNodalInFlow(second.Index, +q);
ls.AddRhsCoeff(n2, +q);
invHeadLoss = 1.0 / Constants.CBIG;
ls.AddAij(smat.GetNdx(k), -invHeadLoss);
ls.AddAii(n1, +invHeadLoss);
ls.AddAii(n2, +invHeadLoss);
flowCorrection = flow - q;
}
else
{
// Otherwise treat valve as an open pipe
ValveCoeff(net);
ls.AddAij(smat.GetNdx(k), -invHeadLoss);
ls.AddAii(n1, +invHeadLoss);
ls.AddAii(n2, +invHeadLoss);
ls.AddRhsCoeff(n1, +(flowCorrection - flow));
ls.AddRhsCoeff(n2, -(flowCorrection - flow));
}
}
/// <summary>Computes matrix coeffs. for emitters.</summary>
/// <remarks>
/// Emitters consist of a fictitious pipe connected to
/// a fictitious reservoir whose elevation equals that
/// of the junction. The headloss through this pipe is
/// Ke*(Flow)^Qexp, where Ke = emitter headloss coeff.
/// </remarks>
public static void ComputeEmitterCoeffs(
EpanetNetwork net,
List <SimulationNode> junctions,
SparseMatrix smat,
LsVariables ls)
{
foreach (SimulationNode node in junctions)
{
if (node.Node.Ke == 0.0)
{
continue;
}
double ke = Math.Max(Constants.CSMALL, node.Node.Ke);
double q = node._emitter;
double z = ke * Math.Pow(Math.Abs(q), net.QExp);
double p = net.QExp * z / Math.Abs(q);
p = p < net.RQtol ? 1.0 / net.RQtol : 1.0 / p;
double y = Utilities.GetSignal(q) * z * p;
ls.AddAii(smat.GetRow(node.Index), +p);
ls.AddRhsCoeff(smat.GetRow(node.Index), +(y + p * node.Node.Elevation));
ls.AddNodalInFlow(node, -q);
}
}
/// <summary>Completes calculation of nodal flow imbalance (X) flow correction (F) arrays.</summary>
public static void ComputeNodeCoeffs(List <SimulationNode> junctions, SparseMatrix smat, LsVariables ls)
{
foreach (SimulationNode node in junctions)
{
ls.AddNodalInFlow(node, -node.demand);
ls.AddRhsCoeff(smat.GetRow(node.Index), +ls.GetNodalInFlow(node));
}
}
/// <summary>Compute P, Y and matrix coeffs.</summary>
private void ComputeMatrixCoeff(
EpanetNetwork net,
PipeHeadModelCalculators.Compute hlModel,
IList <Curve> curves,
SparseMatrix smat,
LsVariables ls)
{
switch (Type)
{
// Pipes
case LinkType.CV:
case LinkType.PIPE:
ComputePipeCoeff(net, hlModel);
break;
// Pumps
case LinkType.PUMP:
((SimulationPump)this).ComputePumpCoeff(net);
break;
// Valves
case LinkType.PBV:
case LinkType.TCV:
case LinkType.GPV:
case LinkType.FCV:
case LinkType.PRV:
case LinkType.PSV:
// If valve status fixed then treat as pipe
// otherwise ignore the valve for now.
if (!((SimulationValve)this).ComputeValveCoeff(net, curves))
{
return;
}
break;
default:
return;
}
int n1 = first.Index;
int n2 = second.Index;
ls.AddNodalInFlow(n1, -flow);
ls.AddNodalInFlow(n2, +flow);
ls.AddAij(smat.GetNdx(Index), -invHeadLoss);
if (!(first is SimulationTank))
{
ls.AddAii(smat.GetRow(n1), +invHeadLoss);
ls.AddRhsCoeff(smat.GetRow(n1), +flowCorrection);
}
else
{
ls.AddRhsCoeff(smat.GetRow(n2), +(invHeadLoss * first.SimHead));
}
if (!(second is SimulationTank))
{
ls.AddAii(smat.GetRow(n2), +invHeadLoss);
ls.AddRhsCoeff(smat.GetRow(n2), -flowCorrection);
}
else
{
ls.AddRhsCoeff(smat.GetRow(n1), +(invHeadLoss * second.SimHead));
}
}