Simulation N° 5: Granular Flow

Build

To build the project, it is necessary to have Maven +3.5.0, and Java SE 8 Release installed. Then, run:

$ mvn clean package

This will generate a *.jar in the target folder. If you find any issues with the building, remove the *.jar files from the Maven local repository with:

$ rm -fr ~/.m2/repository/ar/edu/itba/ss/*

Or do it manually, if you prefer.

Execute

In the root folder (after build):

$ java -jar target/tp5-1.0-SNAPSHOT.jar <simulate | animate | flow>

Configuration

Receives a JSON file with the following format:

{
    "output"            : "res/data/output.data",
    "delta"             : "0.00003",
    "time"              : "15.0",
    "fps"               : "50",
    "playbackSpeed"     : "0.5",
    "samplesPerSecond"  : "200",

    "integrator"        : "BeemanIntegrator",
    "reportEnergy"      : "false",
    "reportTime"        : "true",
    "radius"            : ["0.01", "0.015"],
    "mass"              : "0.01",

    "elasticNormal"     : "1.0E+4",
    "elasticTangent"    : "2.0E+4",
    "viscousDamping"    : "20.0",
    "siloDamping"       : "15.0",

    "generator"         : "64684095347601931",
    "n"                 : "370",
    "height"            : "1.0",
    "width"             : "0.4",
    "drain"             : "0.15",
    "flowRate"          : "0.1",
    "injection"         : ["0.75", "1.0"]
}

Output Files Format

Simulation File (*.data)

The complete simulation results. Includes the speed and pressure over every particle in every simulation step.

<x> <y> <r> <speed> <pressure>
...

Flow Rate File (*.drain)

This file contains the complete drain (i.e., the ID of a particle drained at a certain time).

<t> <id>
...

Windowed Flow Rate File (*.flow)

This is the windowed flow per unit of temporal step. The units are in [particles/second].

<t> <flow>
...

Small Simulation File (*.small)

This is a reduced form of the simulation file, but sub-sampled.

<x> <y> <r> <speed> <pressure>
...

Animation File (*.xyz)

This file can be used in Ovito to render the simulation.

<N>
<t0>
<x> <y> <r> <speed> <pressure>
...

Videos

• Simulation N° 1: Drain 0.15
• Simulation N° 2: Drain 0.19
• Simulation N° 3: Drain 0.23
• Simulation N° 4: Drain 0.27
• Simulation N° 5.1: Steady State (critic damping)
• Simulation N° 5.2: Steady State (over-critic damping)

Developers

This project has been built, designed and maintained by the following authors:

• Daniel Lobo
• Agustín Golmar