  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.
