///<summary>Creates new segments in outflow links from nodes.</summary>
/// <param name="dt">Step duration in seconds.</param>
private void Release(long dt)
{
foreach (QualityLink qL in _links)
{
if (qL.Flow == 0.0)
{
continue;
}
// Find flow volume released to link from upstream node
// (NOTE: Flow volume is allowed to be > link volume.)
QualityNode qN = qL.UpStreamNode;
double q = Math.Abs(qL.Flow);
double v = q * dt;
// Include source contribution in quality released from node.
double c = qN.Quality + qN.SourceContribution;
// If link has a last seg, check if its quality
// differs from that of the flow released from node.
if (qL.Segments.Count > 0)
{
QualitySegment seg = qL.Segments.Last.Value;
// Quality of seg close to that of node
if (Math.Abs(seg.C - c) < _net.Ctol)
{
seg.C = (seg.C * seg.V + c * v) / (seg.V + v);
seg.V += v;
}
else // Otherwise add a new seg to end of link
{
qL.Segments.AddLast(new QualitySegment(v, c));
}
}
else // If link has no segs then add a new one.
{
qL.Segments.AddLast(new QualitySegment(qL.LinkVolume, c));
}
}
}
///<summary>Initializes WQ solver system</summary>
public QualitySim(EpanetNetwork net, TraceSource ignored)
{
// this.log = log;
_net = net;
_nodes = net.Nodes.Select(QualityNode.Create).ToArray();
_tanks = _nodes.OfType <QualityTank>().ToArray();
_juncs = _nodes.Where(x => !(x is QualityTank)).ToArray();
_links = net.Links.Select(n => new QualityLink(net.Nodes, _nodes, n)).ToArray();
/*
* this.nodes = new List<QualityNode>(net.Nodes.Count);
* this.links = new List<QualityLink>(net.Links.Count);
* this.tanks = new List<QualityTank>(net.Tanks.Count());
* this.juncs = new List<QualityNode>(net.Junctions.Count());
*
* foreach (Node n in net.Nodes) {
* QualityNode qN = QualityNode.Create(n);
*
* this.nodes.Add(qN);
*
* var tank = qN as QualityTank;
*
* if (tank != null)
* this.tanks.Add(tank);
* else
* this.juncs.Add(qN);
* }
*
* foreach (Link n in net.Links)
* this.links.Add(new QualityLink(net.Nodes, this.nodes, n));
*
*/
_bucf = 1.0;
_tucf = 1.0;
_reactflag = false;
_qualflag = _net.QualFlag;
if (_qualflag != QualType.NONE)
{
if (_qualflag == QualType.TRACE)
{
foreach (QualityNode qN in _nodes)
{
if (qN.Node.Name.Equals(_net.TraceNode, StringComparison.OrdinalIgnoreCase))
{
_traceNode = qN;
_traceNode.Quality = 100.0;
break;
}
}
}
if (_net.Diffus > 0.0)
{
_sc = _net.Viscos / _net.Diffus;
}
else
{
_sc = 0.0;
}
_bucf = GetUcf(_net.BulkOrder);
_tucf = GetUcf(_net.TankOrder);
_reactflag = GetReactflag();
}
_wbulk = 0.0;
_wwall = 0.0;
_wtank = 0.0;
_wsource = 0.0;
_htime = 0;
_rtime = _net.RStart;
_qtime = 0;
_nperiods = 0;
_elevUnits = _net.FieldsMap.GetUnits(FieldType.ELEV);
}
///<summary>Initializes water quality segments.</summary>
private void Initsegs()
{
foreach (QualityLink qL in _links)
{
qL.FlowDir = true;
if (qL.Flow < 0.0)
{
qL.FlowDir = false;
}
qL.Segments.Clear();
double c;
// Find quality of downstream node
QualityNode j = qL.DownStreamNode;
if (j is QualityTank)
{
c = ((QualityTank)j).Concentration;
}
else
{
c = j.Quality;
}
// Fill link with single segment with this quality
qL.Segments.AddLast(new QualitySegment(qL.LinkVolume, c));
}
// Initialize segments in tanks that use them
foreach (QualityTank qT in _tanks)
{
Tank tank = (Tank)qT.Node;
// Skip reservoirs & complete mix tanks
if (tank.Type == NodeType.RESERV || tank.MixModel == MixType.MIX1)
{
continue;
}
double c = qT.Concentration;
qT.Segments.Clear();
// Add 2 segments for 2-compartment model
if (tank.MixModel == MixType.MIX2)
{
double v = Math.Max(0, qT.Volume - tank.V1Max);
qT.Segments.AddLast(new QualitySegment(v, c));
v = qT.Volume - v;
qT.Segments.AddLast(new QualitySegment(v, c));
}
else
{
// Add one segment for FIFO & LIFO models
double v = qT.Volume;
qT.Segments.AddLast(new QualitySegment(v, c));
}
}
}
///<summary>Accumulates mass flow at nodes and updates nodal quality.</summary>
/// <param name="dt">Step duration in seconds.</param>
private void Accumulate(long dt)
{
// Re-set memory used to accumulate mass & volume
foreach (QualityNode qN in _nodes)
{
qN.VolumeIn = 0;
qN.MassIn = 0;
qN.SourceContribution = 0;
}
foreach (QualityLink qL in _links)
{
QualityNode j = qL.DownStreamNode; // Downstream node
if (qL.Segments.Count > 0) // Accumulate concentrations
{
j.MassIn = j.MassIn + qL.Segments.First.Value.C;
j.VolumeIn = j.VolumeIn + 1;
}
j = qL.UpStreamNode;
if (qL.Segments.Count > 0) // Upstream node
{ // Accumulate concentrations
j.MassIn = j.MassIn + qL.Segments.Last.Value.C;
j.VolumeIn = j.VolumeIn + 1;
}
}
foreach (QualityNode qN in _nodes)
{
if (qN.VolumeIn > 0.0)
{
qN.SourceContribution = qN.MassIn / qN.VolumeIn;
}
}
// Move mass from first segment of each pipe into downstream node
foreach (QualityNode qN in _nodes)
{
qN.VolumeIn = 0;
qN.MassIn = 0;
}
foreach (QualityLink qL in _links)
{
QualityNode j = qL.DownStreamNode;
double v = Math.Abs(qL.Flow) * dt;
while (v > 0.0)
{
if (qL.Segments.Count == 0)
{
break;
}
QualitySegment seg = qL.Segments.First.Value;
// Volume transported from this segment is
// minimum of flow volume & segment volume
// (unless leading segment is also last segment)
double vseg = seg.V;
vseg = Math.Min(vseg, v);
if (qL.Segments.Count == 1)
{
vseg = v;
}
double cseg = seg.C;
j.VolumeIn = j.VolumeIn + vseg;
j.MassIn = j.MassIn + vseg * cseg;
v -= vseg;
// If all of segment's volume was transferred, then
// replace leading segment with the one behind it
// (Note that the current seg is recycled for later use.)
if (v >= 0.0 && vseg >= seg.V)
{
qL.Segments.RemoveFirst();
}
else
{
seg.V -= vseg;
}
}
}
}
