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Added boundary states for correct resonances

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max
2026-05-03 01:52:55 +02:00
parent 3926ed7ef9
commit a006a07049
9 changed files with 432 additions and 244 deletions
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143
Core/Solver.cs
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@@ -10,70 +10,163 @@ namespace FluidSim.Core
private readonly List<Pipe1D> _pipes = new();
private readonly List<Connection> _connections = new();
private double _dt; // global time step
public void AddVolume(Volume0D v) => _volumes.Add(v);
public void AddPipe(Pipe1D p) => _pipes.Add(p);
public void AddConnection(Connection c) => _connections.Add(c);
public void Step()
/// <summary>Set the global time step (called from Simulation).</summary>
public void SetTimeStep(double dt) => _dt = dt;
/// <summary>
/// Convenient method to set the boundary type of a pipe end.
/// </summary>
public void SetPipeBoundary(Pipe1D pipe, bool isLeft, BoundaryType type, double ambientPressure = 101325.0)
{
// 1. Volumes publish state to their ports
if (isLeft)
{
pipe.SetLeftBoundaryType(type);
if (type == BoundaryType.OpenEnd)
pipe.SetLeftAmbientPressure(ambientPressure);
}
else
{
pipe.SetRightBoundaryType(type);
if (type == BoundaryType.OpenEnd)
pipe.SetRightAmbientPressure(ambientPressure);
}
}
public float Step()
{
// 1. Volumes publish state to ports (only needed if any volume exists)
foreach (var v in _volumes)
v.PushStateToPort();
// 2. Set volume states as boundary conditions on pipes
// 2. Set initial pipe boundary conditions ONLY for volume‑coupled ends
foreach (var conn in _connections)
{
if (IsPipePort(conn.PortA) && IsVolumePort(conn.PortB))
SetVolumeBC(conn.PortA, conn.PortB);
{
var pipe = GetPipe(conn.PortA);
bool isLeft = pipe.PortA == conn.PortA;
BoundaryType bc = isLeft ? pipe.LeftBCType : pipe.RightBCType;
if (bc == BoundaryType.VolumeCoupling)
SetVolumeBC(conn.PortA, conn.PortB);
}
else if (IsVolumePort(conn.PortA) && IsPipePort(conn.PortB))
SetVolumeBC(conn.PortB, conn.PortA);
{
var pipe = GetPipe(conn.PortB);
bool isLeft = pipe.PortB == conn.PortB;
BoundaryType bc = isLeft ? pipe.LeftBCType : pipe.RightBCType;
if (bc == BoundaryType.VolumeCoupling)
SetVolumeBC(conn.PortB, conn.PortA);
}
}
// 3. Run pipe simulations
// 3. Determine number of sub‑steps
int nSub = 1;
foreach (var p in _pipes)
p.Simulate();
nSub = Math.Max(nSub, p.GetRequiredSubSteps(_dt));
double dtSub = _dt / nSub;
// 4. Transfer pipe‑port flows to volume ports
foreach (var conn in _connections)
// 4. Sub‑step loop
for (int sub = 0; sub < nSub; sub++)
{
if (IsPipePort(conn.PortA) && IsVolumePort(conn.PortB))
TransferPipeToVolume(conn.PortA, conn.PortB);
else if (IsVolumePort(conn.PortA) && IsPipePort(conn.PortB))
TransferPipeToVolume(conn.PortB, conn.PortA);
foreach (var p in _pipes)
p.SimulateSingleStep(dtSub);
// Transfer flows only for volume‑coupled connections
foreach (var conn in _connections)
{
if (IsPipePort(conn.PortA) && IsVolumePort(conn.PortB))
{
var pipe = GetPipe(conn.PortA);
bool isLeft = pipe.PortA == conn.PortA;
if (pipe.LeftBCType == BoundaryType.VolumeCoupling || pipe.RightBCType == BoundaryType.VolumeCoupling)
TransferAndIntegrate(conn.PortA, conn.PortB, dtSub);
}
else if (IsVolumePort(conn.PortA) && IsPipePort(conn.PortB))
{
var pipe = GetPipe(conn.PortB);
bool isLeft = pipe.PortB == conn.PortB;
if (pipe.LeftBCType == BoundaryType.VolumeCoupling || pipe.RightBCType == BoundaryType.VolumeCoupling)
TransferAndIntegrate(conn.PortB, conn.PortA, dtSub);
}
}
// Update BCs for volume‑coupled ends between sub‑steps
if (sub < nSub - 1)
{
foreach (var v in _volumes)
v.PushStateToPort();
foreach (var conn in _connections)
{
if (IsPipePort(conn.PortA) && IsVolumePort(conn.PortB))
{
var pipe = GetPipe(conn.PortA);
bool isLeft = pipe.PortA == conn.PortA;
if ((isLeft && pipe.LeftBCType == BoundaryType.VolumeCoupling) ||
(!isLeft && pipe.RightBCType == BoundaryType.VolumeCoupling))
SetVolumeBC(conn.PortA, conn.PortB);
}
else if (IsVolumePort(conn.PortA) && IsPipePort(conn.PortB))
{
var pipe = GetPipe(conn.PortB);
bool isLeft = pipe.PortB == conn.PortB;
if ((isLeft && pipe.LeftBCType == BoundaryType.VolumeCoupling) ||
(!isLeft && pipe.RightBCType == BoundaryType.VolumeCoupling))
SetVolumeBC(conn.PortB, conn.PortA);
}
}
}
}
// 5. Integrate volumes
foreach (var v in _volumes)
v.Integrate();
// 5. Audio samples from SoundConnections (if any)
var audioSamples = new List<float>();
foreach (var conn in _connections)
{
if (conn is SoundConnection sc)
audioSamples.Add(sc.GetAudioSample());
}
// 6. Clear volume BC flags
foreach (var p in _pipes)
p.ClearBC();
return SoundProcessor.MixAndClip(audioSamples.ToArray());
}
bool IsVolumePort(Port p) => _volumes.Exists(v => v.Port == p);
bool IsPipePort(Port p) => _pipes.Exists(pp => pp.PortA == p || pp.PortB == p);
Pipe1D GetPipe(Port p) => _pipes.Find(pp => pp.PortA == p || pp.PortB == p);
private bool IsVolumePort(Port p) => _volumes.Exists(v => v.Port == p);
private bool IsPipePort(Port p) => _pipes.Exists(pp => pp.PortA == p || pp.PortB == p);
private Pipe1D GetPipe(Port p) => _pipes.Find(pp => pp.PortA == p || pp.PortB == p);
private Volume0D GetVolume(Port p) => _volumes.Find(v => v.Port == p);
void SetVolumeBC(Port pipePort, Port volPort)
private void SetVolumeBC(Port pipePort, Port volPort)
{
Pipe1D pipe = GetPipe(pipePort);
var pipe = GetPipe(pipePort);
if (pipe == null) return;
bool isLeft = pipe.PortA == pipePort;
if (isLeft)
pipe.SetLeftVolumeState(volPort.Density, volPort.Pressure);
else
pipe.SetRightVolumeState(volPort.Density, volPort.Pressure);
}
void TransferPipeToVolume(Port pipePort, Port volPort)
private void TransferAndIntegrate(Port pipePort, Port volPort, double dtSub)
{
double mdot = pipePort.MassFlowRate;
volPort.MassFlowRate = -mdot;
if (mdot < 0) // pipe → volume
{
// pipePort.SpecificEnthalpy is already total (h + ½u²)
volPort.SpecificEnthalpy = pipePort.SpecificEnthalpy;
}
// else: volume → pipe, volume’s own static enthalpy is used (already set)
// else: volume’s own enthalpy (set by PushStateToPort) is used
GetVolume(volPort)?.Integrate(dtSub);
}
}
}