BasicSolver/3D-seq/src/main.c

@@ -16,6 +16,8 @@
 #include "solver.h"
 #include "timing.h"
 #include "vtkWriter.h"
+#include "particletracing.h"
+
 
 #define G(v, i, j, k) v[(k) * (imax + 2) * (jmax + 2) + (j) * (imax + 2) + (i)]
 
@@ -90,6 +92,8 @@ int main(int argc, char** argv)
     }
     printParameter(&params);
     initSolver(&s, &params);
+    initParticleTracer(&particletracer, &params);
+    printParticleTracerParameters(&particletracer);
 #ifndef VERBOSE
     initProgress(s.te);
 #endif
@@ -110,6 +114,9 @@ int main(int argc, char** argv)
         computeRHS(&s);
         solver_generic[variant - 1](&s);
         adaptUV(&s);
+
+        trace(&particletracer, &solver, s.u, s.v, s.w, t);
+
         t += s.dt;
         
 #ifdef VERBOSE

BasicSolver/3D-seq/src/parameter.c

@@ -88,6 +88,19 @@ void readParameter(Parameter* param, const char* filename)
             PARSE_REAL(w_init);
             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(z1);
+            PARSE_REAL(x2);
+            PARSE_REAL(y2);
+            PARSE_REAL(z2);
+
         }
     }
 

BasicSolver/3D-seq/src/parameter.h

@@ -18,6 +18,11 @@ typedef struct {
     char* name;
     int bcLeft, bcRight, bcBottom, bcTop, bcFront, bcBack;
     double u_init, v_init, w_init, p_init;
+
+    int numberOfParticles;
+    double startTime, injectTimePeriod, writeTimePeriod;
+
+    double x1, y1, z1, x2, y2, z2;
 } Parameter;
 
 void initParameter(Parameter*);

BasicSolver/3D-seq/src/particletracing.c

@@ -0,0 +1,232 @@
+/*
+ * 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 "vtkWriter.h"
+
+#define U(i, j, k)   u[(k) * (imax + 2) * (jmax + 2) + (j) * (imax + 2) + (i)]
+#define V(i, j, k)   v[(k) * (imax + 2) * (jmax + 2) + (j) * (imax + 2) + (i)]
+#define W(i, j, k)   w[(k) * (imax + 2) * (jmax + 2) + (j) * (imax + 2) + (i)]
+
+static int ts = 0;
+void printParticles(ParticleTracer* particletracer)
+{
+    for(int i = 0; i < particletracer->totalParticles; ++i)
+    {
+        printf("Particle position X : %.2f, Y : %.2f, flag : %d\n", particletracer->particlePool[i].x,
+        particletracer->particlePool[i].y,
+        particletracer->particlePool[i].flag);
+    }
+}
+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 = true;
+        ++(particletracer->pointer);
+        ++(particletracer->totalParticles);
+    }
+}
+
+void advanceParticles(ParticleTracer* particletracer, double* restrict u, double* restrict v, double time)
+{
+    int imax = particletracer->imax;
+    int jmax = particletracer->jmax;
+
+
+    double dx = particletracer->dx;
+    double dy = particletracer->dy;
+
+    double xlength = particletracer->xlength;
+    double ylength = particletracer->ylength;
+
+    for(int i = 0; i < particletracer->totalParticles; ++i)
+    {
+        if(particletracer->particlePool[i].flag == true)
+        {
+            double x = particletracer->particlePool[i].x;
+            double y = particletracer->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;
+            particletracer->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;
+            particletracer->particlePool[i].y = new_y;
+
+            // printf("\tOld X : %.2f, New X : %.2f, iCoord : %d\n\tOld Y : %.2f, New Y : %.2f, jCoord : %d\n\n", x, new_x, iCoord, y, new_y, jCoord);
+            // printf("\tU(iCoord - 1, jCoord - 1) : %.2f, U(iCoord, jCoord - 1) : %.2f, U(iCoord - 1, jCoord) : %.2f, U(iCoord, jCoord) : %.2f\n", U(iCoord - 1, jCoord - 1), U(iCoord, jCoord - 1), U(iCoord - 1, jCoord), U(iCoord, jCoord));
+            // printf("\tV(iCoord - 1, jCoord - 1) : %.2f, V(iCoord, jCoord - 1) : %.2f, V(iCoord - 1, jCoord) : %.2f, V(iCoord, jCoord) : %.2f\n\n", V(iCoord - 1, jCoord - 1), V(iCoord, jCoord - 1), V(iCoord - 1, jCoord), V(iCoord, jCoord));
+            // printf("\t U N : %.2f, V N : %.2f\n\n", u_n, v_n);
+            // printf("\t j-1 * (imax + 2) + i-1 = %d with element from U : %.2f", (jCoord - 1) * (200 + 2) + (iCoord - 1), u[(jCoord - 1) * (imax + 2) + (iCoord - 1)]);
+            // printf("\nimax : %d, jmax : %d\n", imax, jmax);
+
+            if (((new_x < 0.0) || (new_x > xlength) || (new_y < 0.0) || (new_y > ylength)))
+            {
+                particletracer->particlePool[i].flag = false;
+            }
+        }
+    }
+}
+
+void freeParticles(ParticleTracer* particletracer)
+{
+    free(particletracer->particlePool);
+    free(particletracer->linSpaceLine);
+}
+
+void writeParticles(ParticleTracer* particletracer, Solver* solver)
+{
+    VtkOptions opts = { .solver = solver, .particletracer = particletracer };
+
+    char filename[50];
+    snprintf(filename, 50, "vtk_files/particles%d.vtk", ts);
+    vtkOpen(&opts, filename, ts);
+    vtkParticle(&opts, "particle");
+    vtkClose(&opts);
+
+    FILE* fp;
+    Particle* particlePool = particletracer->particlePool;
+
+    snprintf(filename, 50, "vis_files/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);
+
+    ++ts;
+}
+
+void initParticleTracer(ParticleTracer* particletracer, Parameter* params)
+{
+    particletracer->numberOfParticles = params->numberOfParticles;
+    particletracer->startTime         = params->startTime;
+    particletracer->injectTimePeriod  = params->injectTimePeriod;
+    particletracer->writeTimePeriod   = params->writeTimePeriod;
+
+    particletracer->dt                = params->dt;
+    particletracer->dx                = params->xlength / params->imax;
+    particletracer->dy                = params->ylength / params->jmax;
+    particletracer->dz                = params->zlength / params->kmax;
+
+
+    particletracer->xlength           = params->xlength;
+    particletracer->ylength           = params->ylength;
+    particletracer->zlength           = params->zlength;
+
+    
+    particletracer->x1                = params->x1;
+    particletracer->y1                = params->y1;
+    particletracer->z1                = params->z1;
+    particletracer->x2                = params->x2;
+    particletracer->y2                = params->y2;
+    particletracer->z2                = params->z2;
+
+    particletracer->lastInjectTime    = params->startTime;
+    particletracer->lastUpdateTime    = params->startTime;
+    particletracer->lastWriteTime     = params->startTime;
+
+    particletracer->pointer           = 0;
+    particletracer->totalParticles    = 0;
+
+    particletracer->imax              = params->imax;
+    particletracer->jmax              = params->jmax;
+    particletracer->kmax              = params->kmax;
+
+    particletracer->estimatedNumParticles = ((params->te - params->startTime) + 2 ) * params->numberOfParticles;
+
+    particletracer->particlePool      = malloc(sizeof(Particle) * particletracer->estimatedNumParticles);
+    particletracer->linSpaceLine      = malloc(sizeof(Particle) * particletracer->numberOfParticles);
+
+    for (int i = 0; i < particletracer->numberOfParticles; ++i) 
+    {
+        double spacing                      = (double)i / (double)(particletracer->numberOfParticles - 1);
+        particletracer->linSpaceLine[i].x   = spacing * particletracer->x1 + (1.0 - spacing) * particletracer->x2;
+        particletracer->linSpaceLine[i].y   = spacing * particletracer->y1 + (1.0 - spacing) * particletracer->y2;
+        particletracer->linSpaceLine[i].z   = spacing * particletracer->z1 + (1.0 - spacing) * particletracer->z2;
+
+        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, z1 : %.2f, x2 : %.2f, y2 : %.2f, z2 : %.2f\n", particletracer->x1, particletracer->y1, particletracer->z1, particletracer->x2, particletracer->y2, particletracer->z2);
+    printf("\tPointer : %d, TotalParticles : %d\n", particletracer->pointer, particletracer->totalParticles);
+    printf("\tdt : %.2f, dx : %.2f, dy : %.2f,  dz : %.2f\n", particletracer->dt, particletracer->dx, particletracer->dy, particletracer->dz);
+}   
+
+void trace(ParticleTracer* particletracer, Solver* solver, double* u, double* v, double* w, double time)
+{
+    if (time >= particletracer->startTime)
+    {
+        //printParticles(particletracer);
+        if( (time - particletracer->lastInjectTime) >= particletracer->injectTimePeriod)
+        {
+            injectParticles(particletracer);
+            particletracer->lastInjectTime = time;
+        }
+        if( (time - particletracer->lastWriteTime) >= particletracer->writeTimePeriod)
+        {
+            writeParticles(particletracer, solver);
+            particletracer->lastWriteTime = time;
+
+        }
+        advanceParticles(particletracer, u, v, w, time);
+        particletracer->lastUpdateTime = time;   
+    }
+}

BasicSolver/3D-seq/src/particletracing.h

@@ -0,0 +1,47 @@
+/*
+ * 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 "allocate.h"
+#include "parameter.h"
+#include "solver.h"
+#include "particletracing.h"
+#include <stdbool.h>
+
+typedef enum COORD { X = 0, Y, NCOORD } COORD;
+typedef struct
+{
+    double x, y, z;
+    bool flag;
+} Particle;
+
+typedef struct {
+    int numberOfParticles, totalParticles;
+    double startTime, injectTimePeriod, writeTimePeriod, lastInjectTime, lastUpdateTime, lastWriteTime;
+
+    int estimatedNumParticles;
+
+    double dx, dy, dz, dt;
+    Particle* linSpaceLine;
+    Particle* particlePool;
+
+    int pointer;
+    
+    double imax, jmax, kmax, xlength, ylength, zlength;
+
+    double x1, y1, x2, y2, z1, z2;
+} ParticleTracer;
+
+void initParticleTracer(ParticleTracer*, Parameter*);
+void injectParticles(ParticleTracer*);
+void advanceParticles(ParticleTracer*, double* , double*, double*, double);
+void freeParticles(ParticleTracer*);
+void writeParticles(ParticleTracer*, Solver*);
+void printParticleTracerParameters(ParticleTracer*);
+void printParticles(ParticleTracer*);
+void trace(ParticleTracer*, Solver*, double* , double* , double* , double);
+#endif