Ducted Assembly Steady State Heat Transfer Software (DASSH_nc) - forked from ANL DASSH

DASSH_nc is the newcleo's fork of the ANL DASSH repository (https://github.com/dassh-dev/dassh).

Author:	Francesco Pepe
Contributor:	Gabriele Ottino

Introduction

The Ducted Assembly Steady State Heat Transfer Software (DASSH) is an open-source tool for calculating temperature and flow distributions in hexagonal, ducted assemblies comprised of wire-wrapped pin bundles. DASSH is intended for use during the design process to provide a rapid assessment of the flow and temperature distribution, especially when assembly designs are in their early stages and not fully developed.

Compared to the original ANL repository, this fork adds the following features:

• improved definition and update of coolant properties in the Material class;
• introduction of radially varying properties and a local approach to calculating the heat transfer coefficient;
• treatment of transverse mixing and mass exchange between subchannels.

The Codes and Methods Department at newcleo manages and maintains this fork in collaboration with Politecnico di Torino.

Project Structure

The project is organized according to the following folder structure:

<dassh parent folder>
├── dassh/
├── tests/
├── LICENSE
├── README.md
├── requirements.txt
└── setup.py

• dassh: contains all modules, classes and methods implemented in DASSH;

• tests: collection of tests used to verify the correct implementation.

Dependencies

To run the code, the following dependencies must be satisfied:

• python>=3.6

• pandas>=1.1.5

• configobj==5.0.6

• pytest==6.2.4

• pytest-cov==2.12.0

• matplotlib>=3.2

• numpy>=1.18

• codecov==2.1.11

• dill==0.3.4

• packaging>=20.0

• sympy==1.13.3

Installation

To install DASSH_nc, clone its repo and execute the following command inside the base folder:

pip install .

Documentation

• User guide: https://github.com/dassh-dev/documents/blob/master/user_guide.pdf

• Theory manual: https://github.com/dassh-dev/documents/blob/master/theory_manual.pdf

How to cite

If you use DASSH_nc in your research, please consider citing the following items:

• Milos Atz, Micheal A. Smith, Florent Heidet. “DASSH software for ducted assembly thermal hydraulics calculations – overview and benchmark”. Transactions of the American Nuclear Society 123 pp. 1673-1676 (2020). URL.

• Milos Atz, Micheal A. Smith, Florent Heidet, "Ducted Assembly Steady State Heat Transfer Software (DASSH) - Theory Manual", ANL/NSE-21/33, Argonne National Laboratory, 2021.

• Milos Atz, Micheal A. Smith, Florent Heidet, "Ducted Assembly Steady State Heat Transfer Software (DASSH) - User Guide", ANL/NSE-21/34, Argonne National Laboratory, 2021.

• Francesco Pepe, Gabriele Ottino, Roberto Bonifetto. "Extension and first validation of dassh subchannel code for liquid metal cooled fast reactors." Annals of Nuclear Energy, 238:112513, 2026.

Contact

For information on this fork and how to contribute to it, please contact gabriele.ottino@newcleo.com.

For information about the original repository, please follow the recommendations provided in the ANL DASSH repository.

License

DASSH_nc is distributed under the BSD-3 license.