Particle Tracer work in progress

BasicSolver/2D-seq/src/main.c

@@ -13,6 +13,7 @@
 #include "parameter.h"
 #include "progress.h"
 #include "solver.h"
+#include "particletracing.h"
 #include "timing.h"
 
 enum VARIANT { SOR = 1, RB, RBA };
@@ -25,6 +26,7 @@ int main (int argc, char** argv)
     double S, E;
     Parameter params;
     Solver solver;
+    ParticleTracer particletracer;
     initParameter(&params);
 
     if (argc < 2) {
@@ -40,6 +42,9 @@ int main (int argc, char** argv)
 
     printParameter(&params);
     initSolver(&solver, &params);
+    initParticleTracer(&particletracer, &params);
+    printParticleTracerParameters(&particletracer);
+
 #ifndef VERBOSE
     initProgress(solver.te);
 #endif
@@ -52,7 +57,7 @@ int main (int argc, char** argv)
     void (*solver_generic[])(solver) = {solve, solveRB, solveRBA};
 
     S = getTimeStamp();
-
+    
     while (t <= te) 
     {
         if (tau > 0.0) computeTimestep(&solver);
@@ -63,19 +68,26 @@ int main (int argc, char** argv)
         if (nt % 100 == 0) normalizePressure(&solver);
         (*solver_generic[variant - 1])(&solver);
         adaptUV(&solver);
+
+        /* Added function for particle tracing. Will inject and advance particles as per timePeriod */
+        trace(&particletracer, solver.u, solver.v, t);
+
         t += solver.dt;
         nt++;
-    
+    /*
     #ifdef VERBOSE
             printf("TIME %f , TIMESTEP %f\n", t, solver.dt);
     #else
             printProgress(t);
     #endif
-    
+    */
     }
     
     E = getTimeStamp();
     stopProgress();
+
+    freeParticles(&particletracer);
+
     printf("Solution took %.2fs\n", E - S);
     writeResult(&solver);
     return EXIT_SUCCESS;

BasicSolver/2D-seq/src/parameter.c

@@ -81,6 +81,15 @@ void readParameter(Parameter* param, const char* filename)
             PARSE_REAL(p_init);
             PARSE_REAL(rho);
 
+            /* Added new particle tracing parameters */
+            PARSE_INT(numberOfParticles);
+            PARSE_REAL(startTime);
+            PARSE_REAL(injectTimePeriod);
+            PARSE_REAL(writeTimePeriod);
+            PARSE_REAL(x1);
+            PARSE_REAL(y1);
+            PARSE_REAL(x2);
+            PARSE_REAL(y2);
         }
     }
 
@@ -113,4 +122,11 @@ void printParameter(Parameter* param)
     printf("\tomega (SOR relaxation): %f\n", param->omg);
     printf("\trho (SOR relaxation): %f\n", param->rho);
 
+    printf("Particle Tracing data:\n");
+    printf("\tNumber of particles : %d being injected for every period of %.2f\n", param->numberOfParticles, param->injectTimePeriod);
+    printf("\tstartTime : %.2f\n", param->startTime);
+    printf("\t(Line along which the particles are to be injected) \n\tx1 : %.2f, y1 : %.2f, x2 : %.2f, y2 : %.2f\n", param->x1, param->y1, param->x2, param->y2);
+
+
+
 }

BasicSolver/2D-seq/src/parameter.h

@@ -18,6 +18,11 @@ typedef struct {
     char* name;
     int bcLeft, bcRight, bcBottom, bcTop;
     double u_init, v_init, p_init;
+
+    int numberOfParticles;
+    double startTime, injectTimePeriod, writeTimePeriod;
+
+    double x1, y1, x2, y2;
 } Parameter;
 
 void initParameter(Parameter*);

BasicSolver/2D-seq/src/particletracing.c

@@ -0,0 +1,203 @@
+/*
+ * Copyright (C) 2022 NHR@FAU, University Erlangen-Nuremberg.
+ * All rights reserved. This file is part of nusif-solver.
+ * Use of this source code is governed by a MIT style
+ * license that can be found in the LICENSE file.
+ */
+#include <float.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "allocate.h"
+#include "parameter.h"
+#include "solver.h"
+#include "particletracing.h"
+#include "util.h"
+
+#define U(i, j) u[(j) * (imax + 2) + (i)]
+#define V(i, j) v[(j) * (imax + 2) + (i)]
+
+static int ts = 0;
+
+void injectParticles(ParticleTracer* particletracer)
+{
+    for(int i = 0; i < particletracer->numberOfParticles; ++i)
+    {
+        particletracer->particlePool[particletracer->pointer].x = particletracer->linSpaceLine[i].x;
+        particletracer->particlePool[particletracer->pointer].y = particletracer->linSpaceLine[i].y;
+        particletracer->particlePool[particletracer->pointer].flag = particletracer->linSpaceLine[i].flag;
+        ++(particletracer->pointer);
+        ++(particletracer->totalParticles);
+    }
+}
+
+void advanceParticles(ParticleTracer* particletracer, double* u, double* v, double time)
+{
+    Particle* particlePool = particletracer->particlePool;
+
+    int imax = particletracer->imax;
+    int jmax = particletracer->jmax;
+
+    double dx = particletracer->dx;
+    double dy = particletracer->dy;
+
+    for(int i = 0; i < particletracer->totalParticles; ++i)
+    {
+        if(particlePool[i].flag == true)
+        {
+            double x = particlePool[i].x;
+            double y = particlePool[i].y;
+
+            int iCoord = (int)(x / dx) + 1;
+            int jCoord = (int)((y + 0.5 * dy) / dy) + 1;
+
+            double x1 = (double)(iCoord - 1) * dx;
+            double y1 = ((double)(jCoord - 1) - 0.5) * dy;
+            double x2 = (double)iCoord * dx;
+            double y2 = ((double)jCoord - 0.5) * dy;
+
+            double u_n = (1.0 / (dx * dy)) *
+                    ((x2 - x) * (y2 - y) * U(iCoord - 1, jCoord - 1) +
+                        (x - x1) * (y2 - y) * U(iCoord, jCoord - 1) +
+                        (x2 - x) * (y - y1) * U(iCoord - 1, jCoord) +
+                        (x - x1) * (y - y1) * U(iCoord, jCoord));
+
+            double new_x = x + particletracer->dt * u_n;
+            particlePool[i].x = new_x;
+
+            iCoord = (int)((x + 0.5 * dx) / dx) + 1;
+            jCoord = (int)(y / dy) + 1;
+
+            x1 = ((double)(iCoord - 1) - 0.5) * dx;
+            y1 = (double)(jCoord - 1) * dy;
+            x2 = ((double)iCoord - 0.5) * dx;
+            y2 = (double)jCoord * dy;
+
+            double v_n = (1.0 / (dx * dy)) *
+                        ((x2 - x) * (y2 - y) * V(iCoord - 1, jCoord - 1) +
+                            (x - x1) * (y2 - y) * V(iCoord, jCoord - 1) +
+                            (x2 - x) * (y - y1) * V(iCoord - 1, jCoord) +
+                            (x - x1) * (y - y1) * V(iCoord, jCoord));
+
+            double new_y = y + particletracer->dt * v_n;
+            particlePool[i].y = new_y;
+        }
+    }
+    
+    double xlength = particletracer->xlength;
+    double ylength = particletracer->ylength;
+
+    for(int i = 0; i < particletracer->totalParticles; ++i)
+    {
+        if(particlePool[i].flag == true)
+        {
+            double x = particlePool[i].x;
+            double y = particlePool[i].y;
+
+            if (((x < 0.0) || (x > xlength) || (y < 0.0) || (y > ylength)))
+            {
+                particletracer->totalParticles -= 1;
+                particlePool[i].flag = false;
+            }
+        }
+    }
+}
+
+void freeParticles(ParticleTracer* particletracer)
+{
+    free(particletracer->particlePool);
+    free(particletracer->linSpaceLine);
+}
+
+void writeParticles(ParticleTracer* particletracer)
+{
+    FILE* fp;
+    Particle* particlePool = particletracer->particlePool;
+
+    char filename[50];
+    snprintf(filename, 50, "particles_%d.dat", ts++);
+    fp = fopen(filename, "w");
+
+    if (fp == NULL) {
+        printf("Error!\n");
+        exit(EXIT_FAILURE);
+    }
+
+    for (int i = 0; i < particletracer->totalParticles; ++i)
+    {
+         if(particlePool[i].flag == true)
+        {
+            double x = particlePool[i].x;
+            double y = particlePool[i].y;
+            fprintf(fp, "%f %f\n", x, y);
+        }
+    }
+    fclose(fp);
+}
+
+void initParticleTracer(ParticleTracer* particletracer, Parameter* params)
+{
+    particletracer->numberOfParticles = params->numberOfParticles;
+    particletracer->startTime         = params->startTime;
+    particletracer->injectTimePeriod  = params->injectTimePeriod;
+    particletracer->writeTimePeriod   = params->writeTimePeriod;
+
+
+    particletracer->x1                = params->x1;
+    particletracer->y1                = params->y1;
+    particletracer->x2                = params->x2;
+    particletracer->y2                = params->y2;
+
+    particletracer->lastInjectTime    = params->startTime;
+    particletracer->lastUpdateTime    = params->startTime;
+    particletracer->lastWriteTime     = params->startTime;
+
+    particletracer->pointer           = 0;
+    particletracer->totalParticles    = 0;
+
+    particletracer->estimatedNumParticles = ((params->te - params->startTime) + 2 ) * params->numberOfParticles;
+
+    particletracer->particlePool      = (Particle*)malloc(sizeof(Particle) * particletracer->estimatedNumParticles);
+    particletracer->linSpaceLine      = (Particle*)malloc(sizeof(Particle) * particletracer->numberOfParticles);
+
+    for (int i = 0; i < particletracer->numberOfParticles; ++i) 
+    {
+        double spacing = (double)i / (double)(particletracer->numberOfParticles - 1);
+        double x       = spacing * particletracer->x1 + (1.0 - spacing) * particletracer->x2;
+        double y       = spacing * particletracer->y1 + (1.0 - spacing) * particletracer->y2;
+
+        particletracer->linSpaceLine[i].x = x;
+        particletracer->linSpaceLine[i].y = y;
+        particletracer->linSpaceLine[i].flag = true;
+    }
+
+}
+
+void printParticleTracerParameters(ParticleTracer* particletracer)
+{
+    printf("Particle Tracing data:\n");
+    printf("\tNumber of particles : %d being injected for every period of %.2f\n", particletracer->numberOfParticles, particletracer->injectTimePeriod);
+    printf("\tstartTime : %.2f\n", particletracer->startTime);
+    printf("\t(Line along which the particles are to be injected) \n\tx1 : %.2f, y1 : %.2f, x2 : %.2f, y2 : %.2f\n", particletracer->x1, particletracer->y1, particletracer->x2, particletracer->y2);
+}
+
+void trace(ParticleTracer* particletracer, double* u, double* v, double time)
+{
+    if (time >= particletracer->startTime)
+    {
+        if( (time - particletracer->lastInjectTime) >= particletracer->injectTimePeriod)
+        {
+            injectParticles(particletracer);
+            particletracer->lastInjectTime = time;
+        }
+        if( (time - particletracer->lastWriteTime) >= particletracer->writeTimePeriod)
+        {
+            writeParticles(particletracer);
+            particletracer->lastWriteTime = time;
+        }
+        advanceParticles(particletracer, u, v, time);
+        particletracer->lastUpdateTime = time;   
+    }
+}

BasicSolver/2D-seq/src/particletracing.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2022 NHR@FAU, University Erlangen-Nuremberg.
+ * All rights reserved. This file is part of nusif-solver.
+ * Use of this source code is governed by a MIT style
+ * license that can be found in the LICENSE file.
+ */
+#ifndef __PARTICLETRACING_H_
+#define __PARTICLETRACING_H_
+#include "parameter.h"
+#include <stdbool.h>
+
+typedef enum COORD { X = 0, Y, NCOORD } COORD;
+typedef struct
+{
+    double x, y;
+    bool flag;
+} Particle;
+
+typedef struct {
+    int numberOfParticles, totalParticles;
+    double startTime, injectTimePeriod, writeTimePeriod, lastInjectTime, lastUpdateTime, lastWriteTime;
+
+    int estimatedNumParticles;
+
+    double dx, dy, dt;
+    Particle* linSpaceLine;
+    Particle* particlePool;
+
+    int pointer;
+    
+    double imax, jmax, xlength, ylength;
+
+    double x1, y1, x2, y2;
+} ParticleTracer;
+
+void initParticleTracer(ParticleTracer*, Parameter*);
+void injectParticles(ParticleTracer*);
+void advanceParticles(ParticleTracer*, double* , double*, double);
+void freeParticles(ParticleTracer*);
+void writeParticles(ParticleTracer*);
+void printParticleTracerParameters(ParticleTracer*);
+void trace(ParticleTracer*, double* , double* , double );
+#endif

BasicSolver/2D-seq/src/solver.c

@@ -243,10 +243,11 @@ void solveRB(Solver* solver)
 #endif
         it++;
     }
-
+/*
 #ifdef VERBOSE
     printf("Solver took %d iterations to reach %f\n", it, sqrt(res));
 #endif
+*/
 }
 
 void solveRBA(Solver* solver)