MSc thesis student: High resolution simulation of heat transfer in sub-channel 
geometry


Background
The Nuclear Research and consultancy Group (NRG) is actively involved in several 
research projects in the nuclear field. A significant effort is dedicated to the 
investigation and development of cutting-edge methodologies that can be 
beneficial for the nuclear engineering community. One application is the high 
resolution simulation of heat transfer in a sub-channel geometry. Understanding 
the heat transfer from fuel rods to coolant is essential in efficient and safe 
operation of nuclear power plants.


Research Proposal
The proposed research will be part of NRG’s HIRES-X project. This project is a 
joint collaboration between NRG, TU Delft, Penn State University and 
Westinghouse. Its overall objective is the validation of high resolution 
simulation codes such as CaNS (developed by TUD) and Briscola (developed by 
NRG), and to compare performance against more established codes such as 
Nek5000/NekRS and OpenFOAM. This MSc. thesis project will deal with the OpenFOAM 
part, using the RKSymFoam solver developed by UPC and NRG 
(https://github.com/janneshopman/RKSymFoam).

The main goal is to perform simulation of heat transfer in sub-channel geometry 
using OpenFOAM. To this end, suitable simulation cases must be defined in 
agreement with other project partners. Next, the RKSymFoam solver must be 
extended to include the energy equation. Furthermore, further optimization of 
the efficiency of selected Runge-Kutta time integration scheme is foreseen. As a 
third step, appropriate meshes should be generated that are designed to 
accurately capture the relevant length scales. Finally, simulations are 
performed and accuracy is measured with as reference both very high resolution 
Nek5000 simulation data and established correlations from the literature 
(Dittus-Boelter).

The project location will be at the NRG|Pallas site in Petten, near Alkmaar, the 
Netherlands. NRG offers a monthly allowance as well as compensation for housing 
and transportation for the period of your stay. 


Objectives/Results
•	Literature review on high-resolution simulation of heat transfer in 
channel, duct and/or sub-channel geometry
•	Implementation and validation of the energy equation in RKSymFoam
•	Optimization of the efficiency of selected Runge-Kutta time integration 
scheme(s)
•	Simulation of heat transfer in selected sub-channel geometries for a 
range of meshes
•	Assessment of results and comparison with reference data and 
correlations


Your profile
•	MSc. student in applied science, with specialization in computational 
fluid mechanics
•	Good knowledge of turbulence modelling and numerical methods
•	Required computer experience: Linux, Windows, Python, C/C++, Git 
•	Fluency in written and spoken English
•	Excellent analytical and problem solving skills
•	An interest in scientific research and publication
•	Creativity, independence, dedication, and good communication and social 
skills
•	MSc thesis student from within the EU.


Our offer
•	A challenging thesis project to be executed within a successful team 
with an informal atmosphere and an excellent reputation
•	Strong support from enthusiastic members of the CFD team 
•	Monthly allowance/stipend
•	Housing and transportation compensation for the period of stay

Contact details and for more information
Dr.ir. Akshat Mathur
mathur@nrg.eu