SCAcode

A steady-state, 1-D, nuclear reactor thermal hydraulics single channel analysis code

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Introduction

SCAcode is intended to determine temperature, both radially throughout a fuel pin and of the moderator (water), and pressure loss within an ideal single channel within a nuclear reactor fuel assembly unit cell. It assumes steady state conditions and a nominal (cosine) flux shape throughout the core.

The fundamental principles of this work can be found in: Nuclear Systems I: Thermal Hydraulic Fundamentals, N.E. Todreas and M.S. Kazimi, 2011 (2nd edition), (ISBN: 9781439808870).

Getting Started

Requirements

See also requirements.txt

• numpy
• matplotlib
• pandas
• scipy

Inputs

Input files must be python files. All variables within the provided input files (./inputs/inp_Benchmark_1_PWR_SCB_True.py and ./inputs/inp_Benchmark_2_BWR_SCB_True.py) must be defined. The values included are reasonable for each design. g and SB_constant should not be modified unless you are modeling a reactor on a different planet or in a different universe.

Outputs

Results will be exported to ./outputs/ into a new folder for each run. Data csv file and a single png plot are created every run.

Useage

If within current directory

python SCAcode_Setup.py -i <./local/path/to/input/file>.py  

If not

python SCAcode_Setup.py -i </entire/path/to/input/file>.py  

Known Issues and Limitations

The following limitations apply based on physical limitation of the systems the code is intended to model (e.g., the fuel can not have melted for this model to be valid and water must boil in a boiling water reactor) and the limitations of mathematical equations/models used:

Type	Limit
Physical	Fuel melting
Physical	Cladding phase transition
Physical	Surpassing critical heat flux (CHF)
Physical	BWR-specific, boiling must occur ($0 < x_e < 1$)
Physical	PWR-specific, amount of permitted boiling ($x_e < 0$)
Physical	PWR-specific, power minimum ($q\prime \geq 0$)
Model	Decoupled momentum and energy equations ($\Delta P_{tot}/P_{abs} \leq 10 %$)
Model	Cheng-Todreas, turbulent flow (Re $> 10^4$) required
Model	Weisman, turbulent flow ($Re > 10^4$) required
Model	HEM, mass flux upper limit
Model	Schrock and Grossman, turbulent flow ($Re > 10^4$) required
Model	Schrock and Grossman, $q\prime < CHF$
Model	Bowring, turbulent flow ($Re > 10^4$) required
Model	Bowring, mass flux limit

Version History

• v1.1.0: Conversion from pd to np for speed. BAT, 230520
• v1.0.0: initial release. BAT, 230512

License

GNU GPL v3.0

Authors

Brice Turner

Acknowledgments

This work would not have been possible without the teachings of DuWayne Scubring, PhD, of the University of Florida.