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ALFRED: ALl particle in Fission Reactor - Energy Deposition

Description

ALFRED is a Geant4-based code designed to compute energy deposition in critical systems such as the TREAT reactor.

Keywords: Energy deposition - TREAT - high fidelity - Geant4 - eigenvalue

Installation

To install ALFRED, follow these steps:

1. Install the Geant4 framework. Follow the instructions on the website: https://geant4.web.cern.ch/docs/getting-started. The following installation has been tested. It is assumed that zlib and qt are already installed:

git clone https://github.com/Geant4/geant4.git
cd geant4
mkdir build
mkdir install 
cd build
cmake -DCMAKE_INSTALL_PREFIX=path/to/install/ -DGEANT4_USE_QT=ON ..
cmake -DGEANT4_INSTALL_DATA=ON .
make -j8
make install

The use of qt is not mandatory but strongly recommended.

2. Clone ALFRED on your system:

git clone XXX
cd ALFRED

3. Create a build directory:

mkdir build
cd build
cmake ..
make -j 4

4. Run ALFRED:

./alfred

Utilization

1. Create runs folders:

cd ./ALFRED
mkdir runs
mkdir runs/run00
cd runs/run00

2. Run ALFRED with eigenvalue.mac in the run folder:

../../build/alfred ../../eigenvalue.mac > listing

Once the run is completed, a listing file and several .csv files should appear.

3. You can process the listing file:

python ../../scripts/energy_deposition.py listing

Materials and Geometry Definition

Materials and geometry are defined in DetectorConstruction.cc. It is a simple model of the TREAT reactor. The user should define their own geometry:

G4VPhysicalVolume* DetectorConstruction::ConstructVolumes()
{
   /**
      geometry definition
   **/
  return fPhysiWorld
}

Physics List

ALFRED uses the Shielding physics list. It is declared in the main.cc file:

G4PhysListFactory* factory = new G4PhysListFactory();
G4VModularPhysicsList* physics = factory->GetReferencePhysList("Shielding");
physics->RegisterPhysics(new G4ThermalNeutrons());

The user can modify the physics list as needed. ALFRED uses the standard G4ENDL nuclear data library. However, the user can use any other library: https://www-nds.iaea.org/geant4/.

Run Action

Each run corresponds to a batch of a given number of particles. The source particle is sampled based on the neutron fission sites and energy tallied in the previous batch. The user can recover the sources for each run with CSV files created: Sources_[batch]_nt_FS_0.csv. Running several batches consists of solving the eigenvalue problem with all particles involved in the fission process being simulated. The user has to define their own variables and functions to tally the desired quantities.

Multithreading

Multithreaded runs have not yet been implemented.