phasicFlow/utilities/geometryPhasicFlow/README.md

geometryPhasicFlow Utility

Overview

geometryPhasicFlow is a preprocessing utility for Discrete Element Method (DEM) simulations in phasicFlow. It converts wall geometry definitions from the geometryDict file into the internal geometry data structures used by the phasicFlow simulation engine.

This utility reads geometry definitions including wall types, material properties, and motion models from the geometryDict file located in the settings folder of your simulation case directory. It then processes these definitions to create the necessary triangulated surfaces and motion models that will be used during the simulation.

Usage

Run the utility from your case directory containing the settings folder:

geometryPhasicFlow

For fluid-particle coupling simulations:

geometryPhasicFlow -c

Wall Types

phasicFlow supports several built-in wall types that can be defined in the geometryDict:

1. planeWall - Flat wall defined by four points (p1, p2, p3, p4)
2. cylinderWall - Cylindrical wall defined by two axis points and radius
3. cuboidWall - Box-shaped wall defined by center point and dimensions
4. stlWall - Complex geometry imported from an STL file

Motion Models

Walls can be associated with different motion models:

1. stationary - Fixed walls (no movement)
2. rotatingAxis - Rotation around a specified axis
3. multiRotatingAxis - Multiple rotations (for complex motions)
4. vibrating - Oscillating motion with specified frequency and amplitude
5. conveyorBelt - Creates a conveyor belt effect with constant tangential velocity

geometryDict File Structure

The geometryDict file requires the following structure:

// Motion model selection
motionModel <motionModelName>;

// Motion model specific information
<motionModelName>Info
{
    // Motion model parameters
    // ...
}

// Wall surfaces definitions
surfaces
{
    <wallName1>
    {
        type        <wallType>;      // Wall type (planeWall, cylinderWall, etc.)
        // Wall type specific parameters
        // ...
        material    <materialName>;  // Material name for this wall
        motion      <motionName>;    // Motion component name
    }
    
    <wallName2>
    {
        // Another wall definition
        // ...
    }
    
    // Additional walls as needed
}

Example

Here's a simple example of a geometryDict file for a rotating drum:

// Rotation around an axis
motionModel rotatingAxis;

rotatingAxisInfo
{
    rotAxis 
    {
        p1        (0.0 0.0 0.0);    // First point for axis of rotation
        p2        (0.0 0.0 1.0);    // Second point for axis of rotation
        omega     1.214;            // Rotation speed (rad/s)
    }
}

surfaces
{
    cylinder
    {
        type        cylinderWall;    // Type of wall
        p1          (0.0 0.0 0.0);   // Begin point of cylinder axis
        p2          (0.0 0.0 0.1);   // End point of cylinder axis
        radius1     0.12;            // Radius at p1
        radius2     0.12;            // Radius at p2
        resolution  24;              // Number of divisions
        material    prop1;           // Material name
        motion      rotAxis;         // Motion component name
    }
    
    wall1
    {
        type        planeWall;       // Type of wall
        p1          (-0.12 -0.12 0.0); // First point
        p2          ( 0.12 -0.12 0.0); // Second point
        p3          ( 0.12  0.12 0.0); // Third point
        p4          (-0.12  0.12 0.0); // Fourth point
        material    prop1;           // Material name
        motion      rotAxis;         // Motion component name
    }
}

STL File Support

For complex geometries, you can use STL files:

wallName
{
    type        stlWall;         // Type is STL wall
    file        filename.stl;    // File name in ./stl folder
    scale       1.0;             // Optional scale for changing the size of surface
    transform   (0 0 0);         // Optional translation vector
    scaleFirst  Yes;             // Scale first or translate first
    material    wallMat;         // Material name
    motion      rotAxis;         // Motion component name
}

STL files should be placed in an stl folder in your case directory.

See Also

• particlesPhasicFlow - Utility for creating initial particle configurations
• pFlowToVTK - Utility for converting simulation results to VTK format
• Tutorials - Example cases demonstrating phasicFlow capabilities