Development of methods for thermo-hydraulic simulation of nuclear reactors and similar systems in normal working conditions and in transient processes

TL;DR

This paper develops a numerical CFD methodology for simulating natural convection compressible flows with high temperature differences and complex geometries, relevant for nuclear reactor core analysis.

Contribution

It introduces a comprehensive CFD-based approach combining pressure algorithms and immersed boundary methods for complex, high-temperature convection flows.

Findings

Verification against literature data confirms accuracy.

Method successfully models high temperature difference flows.

Results demonstrate applicability to nuclear reactor simulations.

Abstract

The goal of this report is to present the final project conducted in order to fulfill the requirements of the M.Sc. degree at the Department of Mechanical Engineering, Ben-Gurion University (BGU) of the Negev. The project comprises theoretical research investigating natural convection compressible flow with high temperature differences and with complex geometries. The research motivation comes from long-term research investigating and simulating the steady state and transient multiphase flow regimes existing in the reactor core, that was established by the Soreq Nuclear Center. The main objective of this project is to develop a comprehensive numerical methodology that is capable of theoretical modeling of natural convection compressible flow with high temperature differences and with complex geometries, using standard techniques of computational fluid dynamics (CFD) - pressure-based solution algorithms and immersed boundary methods. This report contains: - A comprehensive literature review surveying methods for the simulation of natural convection flow and immersed boundary methods. - An extended outline of the objectives of the performed research. - A comprehensive physical model, including the governing equations, definitions, constitutive laws, and dimensional analysis. - A verification study by favorable comparison with corresponding independent numerical data available in the literature for incompressible, and non-Bossinesq compressible flows, without complex geometry. - A comparison between results obtained in the present study and results from previous studies for configurations with low temperature difference and complex geometry. - A solution and analysis of the configurations with high temperature differences and complex geometry. - A summary, conclusions , and recommendations for possible future work.