From 37c86b732836b3425fc44f1a3840d86b98685b77 Mon Sep 17 00:00:00 2001
From: cemf4 <homa.farahani94.com>
Date: Sun, 8 Jun 2025 12:29:33 +0330
Subject: [PATCH] READMEPostprocess.md
---
READMEPostprocess.md | 208 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 208 insertions(+)
create mode 100644 READMEPostprocess.md
diff --git a/READMEPostprocess.md b/READMEPostprocess.md
new file mode 100644
index 00000000..941f973a
--- /dev/null
+++ b/READMEPostprocess.md
@@ -0,0 +1,208 @@
+# phasicFlow `processDataDict` File Explanation
+## Problem definition
+ There is a rotating drum with the diameter 0.24 m and the length 0.1 m rotating at 11.6 rpm. It is filled with 30,000 4-mm spherical particles. The timestep for integration is 0.00001 s.The problem is to postprocessing some data such as velocity, position, one, mass.
+
+
+
+## Setting up the case
+
+ To postprocess these data, we should configurate `processDataDict` file. The code is divided into the following two main parts: 1. Time Control Configuration 2. Components.
+
+## Time Control Configuration
+
+### `defaultTimeControl`
+Defines default time management for processing tasks:
+
+
+```cpp
+ defaultTimeControl
+
+ {
+ timeControl timeStep; //Time stepping mode
+ startTime 0; //Start time for post-processing
+ executionInterval 10000; //Interval between processing events
+ }
+ ```
+
+
+
+## Components
+
+Each entry in the `components` section specifies a different post-processing task as shown below. After running the code, a file with the same name is generated in the simulation folder, containing the data.
+
+### 1. `velocityProb`
+- **Purpose**: Probe the y-component of velocity for specific particles.
+
+
+```cpp
+velocityProb
+ {
+ processMethod particleProbe; //probes at selected particles
+ processRegion centerPoints; //at particle centers
+
+ timeControl default; //Uses default time control.
+
+ selector id; //selected particles by particle ID
+
+ ids (0 10 20 100 1000); //list of particle IDs that has beeen selected arbitrarily.
+
+ field component(velocity,y); //y-component of velocity
+
+ }
+
+```
+
+### 2. `positionProb`
+- **Purpose**: Probe positions at randomly selected points.
+
+```cpp
+positionProb
+ {
+ processMethod particleProbe;
+ processRegion centerPoints;
+
+ timeControl settingsDict; //Uses `settingsDict` time control.
+
+ selector randomPoints; //selects by random points.
+
+ randomPointsInfo
+ {
+ begin 0; //start of rang
+ end 20000; //end of rang
+ number 20; //number of points
+ }
+
+ field position;
+
+ }
+
+
+```
+
+### 3. `alongALine`
+- **Purpose**: Compute statistics along a line, dividing it into spheres (probes).
+
+```cpp
+alongALine
+ {
+ processMethod arithmetic;
+ processRegion line;
+
+ // 10 spheres with radius 0.01 along the straight line defined by p1 and p2
+ lineInfo
+ {
+ p1 ( 0 0 0.05);
+ p2 (0.084 -0.084 0.05);
+ nSpheres 10;
+ radius 0.01;
+ }
+
+ timeControl simulationTime; //custom time control.
+
+ executionInterval 0.1;
+
+ startTime 0.4;
+
+ operations
+ (
+ avVelocity1 // Average velocity magnitude (mass-weighted, with fluctuation)
+ {
+ function average;
+ field mag(velocity);
+ fluctuation2 yes;
+ phi mass;
+ }
+
+ numberDensity1 //Number density (normalized by volume, threshold 10)
+ {
+ function sum;
+ field one;
+ divideByVolume yes;
+ threshold 10;
+ }
+
+ parCount1 //Particle count (sum)
+ {
+ function sum;
+ field one;
+ }
+
+ volFrac1 //Volume fraction (normalized by volume, threshold 4)
+ {
+ function sum;
+ field volume;
+ divideByVolume yes;
+ threshold 4;
+ }
+ );
+ }
+
+
+```
+
+### 4. `alongALine2`
+- **Purpose**: Compute Gaussian-distributed statistics along a line.
+
+
+
+```cpp
+alongALine2
+ {
+ processMethod GaussianDistribution;
+ processRegion line;
+
+ // 10 spheres with radius 0.01 along the straight line defined by p1 and p2
+ lineInfo
+ {
+ p1 ( 0 0 0.05);
+ p2 (0.084 -0.084 0.05);
+ nSpheres 10;
+ radius 0.01;
+ }
+
+ timeControl timeStep;
+
+ executionInterval 100;
+
+ startTime 0;
+
+ operations
+ (
+ avVelocity //Average velocity magnitude (mass-weighted)
+ {
+ function average;
+ field mag(velocity);
+ phi mass;
+ }
+
+ bulkDensity //Bulk density (sum of mass, volume-normalized, threshold 5)
+ {
+ function sum;
+ field mass;
+ phi one;
+ divideByVolume yes;
+ threshold 5;
+ }
+
+ parCount //Particle count
+ {
+ function sum;
+ field one;
+ }
+
+ volFrac //Volume fraction (volume-normalized, threshold 4)
+
+ {
+ function sum;
+ field volume;
+ divideByVolume yes;
+ threshold 4;
+ }
+ );
+ }
+
+
+
+
+
+```
\ No newline at end of file