Numerical study of turbulent thermal convection in water pools of different aspect ratios and different heat loadings

Thermal convection is a classical problem in fluid mechanics: it consists of the motion of a fluid layer that is heated from below and cooled from above. Such a flow is ever present in nature (e.g. atmospheric convection) and employed in industrial applications (e.g. power stations). In this Master thesis we propose a numerical study of turbulent thermal convection in simplified model of water pools of different aspect ratios. The motivation for studying convection in water pools comes from the need to improve our understanding of the functioning of storage pools of spent fuel in nuclear power stations. This study will be based on Large -Eddy Simulations (LES). According to this methodology, the mass, momentum and energy equations are space filtered. In this manner, the large turbulent scales of the flow are directly resolved, whereas the effect of the small, unresolved turbulent scales is included via the introduction of additional terms in the equations. These terms are called "sub-grid scale" (SGS) model. In this study different aspect (height-to-width) ratios and different heat loadings will be considered and the emerging turbulent structures and turbulence statistics will be compared.