ADS-IDACDynamic PRA Simulation Engine

Accident Dynamics Simulator with the IDAC Crew Cognitive Model — NC State PRAG

Thermalhydraulic Plant Model

RELAP5-based simulation tracking reactor coolant conditions, safety system actuations, and mitigating system responses during accident transients.

Read the overview

🧠

IDAC Crew Cognitive Model

Models crew members through information processing, diagnosis, goal selection, strategy selection, and procedure execution within a dynamic event tree.

Process flowcharts

🌳

Dynamic Event Trees

Branches at discrete points in time based on crew decisions, hardware failures, and procedural paths. Probability calculated as the product of conditional branch probabilities.

Branch generation

📂

Input File Format

Detailed format specifications for every input file — action taker, decision maker, procedures, plant hardware, and simulation control.

Input file reference

⚡

Parallel Execution

MPI parallel mode with peer-to-peer restart transfers, adaptive memory limits, LZ4 compression, and real-time DET visualization.

CLI reference

🛠️

Developer Internals

Code architecture, simulation flow, module documentation, Fortran/C++ interface, and source code layout for contributors.

Developer guide

Code Status

The ADS-IDAC simulation code is still under development. Verification and validation activities are ongoing. Users are urged to independently verify all results obtained from the code.

Before Running ADS-IDAC

Review General Note 6 on input file consistency. Cross-references between input files are numerous, and inconsistencies cause runtime errors that can be difficult to diagnose.

Manual Organization

Section	Description
Getting Started	Building, running, output files, cluster use, troubleshooting, reference baselines, packaging
Introduction	Overview of the modeling elements, process flowcharts, and user guidance
Modeling Guidance	Crew variability modeling; RELAP5 reactor plant model development
File Structure	Project directory layout and the files in it
Input File Format	Content and format of every input file
Term Conversions	Integer term conversion table (range 3000 to 3165)
Developer	Solver interface, fault tree quantification, restart trimming, output layouts, engine internals
Tools	The `adsmd` input validator
References	Reference list
API	Doxygen reference for `src/ADSIDAC`, `src/BNCore` and `src/FaultTree`

Naming Conventions

Document Notation

Convention	Meaning
Bold italics	An input variable that must be provided by the analyst
`"quoted name"`	An input file name
`[bracketed item]`	An optional or conditional parameter
`.` (three dot lines)	Multiple entries of the same type are permitted

File Naming Prefixes

Prefix	Applies To	Description
`OAT`	File names	Files associated with the Action Taker (Reactor Operator)
`ODM`	File names	Files associated with the Decision Maker (Shift Supervisor / SRO)
`KB_`	File names	Operator knowledge base files
`ZProcedure_`	File names	Individual procedure step files
`ZProcedure_MPBG_`	File names	Mental procedure files (belief-generated)
`ZProcedure_FRG_`	File names	Functional recovery guideline files
`X_`	Variable/control names	Controls manipulable by operators
`A_`	Alarm names	Alarm identifiers (recommended; not mandatory)

Crew Member Roles

Role	Acronym	Represents	Capabilities
Decision Maker	ODM	Shift Supervisor / Senior Reactor Operator	Initiates and transitions between all procedure types
Action Taker	OAT	Reactor Operator	Initiates and transitions between mental procedures only