orifice confirmed working

This commit is contained in:
2026-05-07 13:28:41 +02:00
parent 685b48b577
commit f79cf6b7eb
5 changed files with 143 additions and 150 deletions

View File

@@ -3,60 +3,74 @@ using SFML.Graphics;
using SFML.System;
using FluidSim.Components;
using FluidSim.Core;
using FluidSim.Utils;
namespace FluidSim.Tests
{
public class TestScenario : Scenario
{
private Solver solver;
private Volume0D volume;
private Pipe1D pipe;
private OrificeLink closedEnd; // left end closed wall
private OpenEndLink openEndLink; // right end atmosphere
private OrificeLink orifice; // volume → pipe left
private OpenEndLink openEnd; // pipe right atmosphere
private SoundProcessor soundProcessor;
private OutdoorExhaustReverb reverb;
private int stepCount;
private double simTime; // elapsed simulation time (seconds)
private double pulseInterval = 0.1; // seconds between pulses
private double nextPulseTime;
// Pressure reset scheduling
private double simTime;
private double dt;
private double resetInterval = 0.2; // seconds between resets
private double nextResetTime;
private double targetPressure = 10 * Units.atm;
private double rampDuration = 0.002; // 2 ms ramp
private double rampStartTime;
private double rampStartPressure; // pressure when ramp started
private bool ramping;
public override void Initialize(int sampleRate)
{
dt = 1.0 / sampleRate;
soundProcessor = new SoundProcessor(sampleRate, 1);
soundProcessor.Gain = 10;
reverb = new OutdoorExhaustReverb(sampleRate);
soundProcessor.Gain = 2.0f; // lower gain to avoid clipping
solver = new Solver();
solver.SetTimeStep(dt);
solver.CflTarget = 0.4;
// Pipe: 2 m long, 1 cm² area, 200 cells
pipe = new Pipe1D(length: 2, area: 1e-4, cellCount: 100);
volume = new Volume0D(1e-3, targetPressure, 300.0);
solver.AddComponent(volume);
pipe = new Pipe1D(1.0, 1e-4, 200);
pipe.EnergyRelaxationRate = 10;
solver.AddComponent(pipe);
// Initially pipe at ambient conditions
pipe.SetUniformState(1.225, 0.0, 101325.0);
var volPort = volume.CreatePort();
double orificeArea = 1e-5;
orifice = new OrificeLink(volPort, pipe, isPipeLeftEnd: true,
areaProvider: () => orificeArea)
{
DischargeCoefficient = 0.62,
UseInertance = true,
EffectiveLength = 0.001
};
solver.AddOrificeLink(orifice);
// Left end: closed wall (area = 0 → reflective)
closedEnd = new OrificeLink(null, pipe, isPipeLeftEnd: true, areaProvider: () => 0.0);
solver.AddOrificeLink(closedEnd);
// Right end: open to atmosphere
openEndLink = new OpenEndLink(pipe, isLeftEnd: false)
openEnd = new OpenEndLink(pipe, isLeftEnd: false)
{
AmbientPressure = 101325.0,
Gamma = 1.4
};
solver.AddOpenEndLink(openEndLink);
solver.AddOpenEndLink(openEnd);
stepCount = 0;
simTime = 0.0;
nextPulseTime = pulseInterval; // first pulse at 100 ms
nextResetTime = resetInterval;
ramping = false;
Console.WriteLine("Pulse reflection test closed left, open right");
Console.WriteLine("Pulse injected every 100 ms at left end (cell 0)");
Console.WriteLine("Pressure reset test with smooth ramp");
Console.WriteLine($"Volume 1L, reset to {targetPressure} Pa every {resetInterval*1000} ms, ramp {rampDuration*1000} ms");
}
public override float Process()
@@ -65,59 +79,54 @@ namespace FluidSim.Tests
stepCount++;
simTime += dt;
// ---- Inject a pressure pulse at the closed end every 100 ms ----
if (simTime >= nextPulseTime)
// ---- Smooth pressure ramp ----
if (ramping)
{
// Apply a Gaussian pulse to the first few cells
double ambientPressure = 101325.0;
double pulseAmplitude = 20 * ambientPressure; // 0.5 atm overpressure
double pulseWidth = 0.05; // m (spread over a few cells)
int n = pipe.CellCount;
double dx = 2.0 / n;
// Only modify cells within 2*pulseWidth from the left end
int maxCell = Math.Min(5, n - 1); // at most the first 5 cells
for (int i = 0; i <= maxCell; i++)
double elapsed = simTime - rampStartTime;
if (elapsed >= rampDuration)
{
double x = (i + 0.5) * dx;
double P = pulseAmplitude * Math.Exp(-x * x / (pulseWidth * pulseWidth));
double currentP = pipe.GetCellPressure(i);
double newP = P;
// Update pressure, keeping density and velocity unchanged
// We recompute total energy accordingly
double rho = pipe.GetCellDensity(i);
double u = pipe.GetCellVelocity(i);
double e = newP / ((1.4 - 1.0) * rho);
double E = rho * e + 0.5 * rho * u * u;
pipe.SetCellState(i, rho, u, newP);
// Ramp finished, set exactly to target
volume.SetPressure(targetPressure);
ramping = false;
}
else
{
double frac = elapsed / rampDuration;
double currentTarget = rampStartPressure + (targetPressure - rampStartPressure) * frac;
volume.SetPressure(currentTarget);
}
Console.WriteLine($"Pulse injected at t = {simTime:F3} s");
nextPulseTime += pulseInterval;
}
// Audio from openend mass flow
float sample = soundProcessor.Process(openEndLink);
// Log every 200 steps
if (stepCount % 1000 == 0)
// ---- Trigger a new reset ----
if (!ramping && simTime >= nextResetTime)
{
int leftIdx = 0;
int midIdx = pipe.CellCount / 2;
int rightIdx = pipe.CellCount - 1;
double pL = pipe.GetCellPressure(leftIdx);
double pM = pipe.GetCellPressure(midIdx);
double pR = pipe.GetCellPressure(rightIdx);
rampStartPressure = volume.Pressure; // current pressure before reset
rampStartTime = simTime;
ramping = true;
nextResetTime += resetInterval;
}
Console.WriteLine($"Step {stepCount}: P_left={pL:F1} Pa, P_mid={pM:F1} Pa, P_right={pR:F1} Pa");
// Log every 500 steps
if (stepCount % 500 == 0)
{
double volP = volume.Pressure;
double pipeL = pipe.GetCellPressure(0);
double pipeR = pipe.GetCellPressure(pipe.CellCount - 1);
double mdotOrif = orifice.LastMassFlowRate;
double mdotOpen = openEnd.LastMassFlowRate;
Console.WriteLine($"Step {stepCount}: " +
$"VolP={volP:F1} Pa, PipeL={pipeL:F1}, PipeR={pipeR:F1}, " +
$"mdot_orif={mdotOrif:E4} kg/s, mdot_open={mdotOpen:E4} kg/s");
}
if (double.IsNaN(pipe.GetCellPressure(0)))
{
Console.WriteLine("NaN detected stopping simulation.");
Console.WriteLine("NaN detected stopping.");
return 0f;
}
return reverb.Process(sample);
return soundProcessor.Process(openEnd);
}
public override void Draw(RenderWindow target)