2. Input Overview

2.1. Input Modules

RMC’s input file is divided into modules. The names and corresponding functions of each module are as follows:

• SURFACE module: Defines surface types and surface equations.
• UNIVERSE module: Describes a complete geometric space. RMC uses a hierarchical space-based geometry description, and multiple UNIVERSE modules may exist in the input file.
• MATERIAL module: Defines material composition.
• CRITICALITY module: Defines criticality calculation parameters, including particle numbers, initial sources, etc.
• TALLY module: Defines tallies, including flux, power, reaction rates, etc.
• CONVERGENCE module: Defines source convergence diagnostics and acceleration parameters.
• BURNUP module: Defines burnup calculation parameters, including burnup cells, power, time steps, etc.
• PRINT module: Defines output print content.
• PLOT module: Defines plotting parameters.
• FIXEDSOURCE module: Defines fixed source calculation parameters, mainly including the number of initial source particles to be simulated.
• EXTERNALSOURCE module: Defines external source particle information, including particle type, position, direction, and energy distribution.
• PHYSICS module: Defines physical parameters for neutron-photon-electron coupled transport calculations.
• GROUPCONSTANT module: Defines group constants and cross-section parameterization calculation parameters.
• RESTARTBINARY module: Defines output parameters for checkpoint continuation calculation files.
• BINARYOUT module: Defines the output parameters for continuation surface source calculation files.
• PTRAC module: Defines particle event tracking parameters.
• WEIGHTWINDOW module: Defines weight window parameters.
• MCNPWEIGHTWINDOW module: Defines MCNP format weight window parameters.
• KINETICS module: Defines stochastic neutron kinetics calculation parameters.
• CONTROL module: Defines control parameters for some of RMC’s running characteristics, such as Hash function selection parameters.
• REFUELLING module: Defines refueling parameters.
• INCLUDE module: Used for file inclusion.
• SERIALIZE module: Defines output parameters for serialized restart data files.

2.2. Input Format

The following points should be noted for the format of RMC input files:

1. Each module is identified by its corresponding keyword, and modules are separated by blank lines. For example:

   Universe 0
   
   ……
   
   Universe 1
   
   ……
   
   Surface
   
   ……
   
   Material
   
   ……
   
   Criticality
   
   ……
   

2. Input cards are written in the top row of each module, and options within input cards are separated by spaces. If an input card is not completed in one line, it can be continued on the next line with a space. For example:

   CellTally 2 type = 1 filter = 1 0 1 energy = 0 6.25E-7 20.0
               cell = 2 > 0 > 1:289
   

3. The comment symbol uses “//” (C++ style).

4. RMC input files are case-insensitive.

5. On Windows system, it is not recommended to use txt format text files as input files. It is recommended to use UltraEdit to convert all input files to Dos format.