Hydraulic Assessment of the MYRRHA Primary Heat Exchanger

One of the most important questions when designing an instal- lation which produces power, such as a nuclear power plant, or an Accelerator Driven System (ADS), is how that power is going to be removed from the system. In that sense, the restriction on design is not coming from the viewpoint of the amount of power that could be produced, but from the viewpoint of the power that could be safely removed. The main component responsible of the heat removal from the Primary System is the Primary Heat Exchanger. It is thus of eminent importance to evaluate and to assess correctly its thermal-hydraulic behavior. This master thesis presents results of CFD analysis performed on the Primary Heat Exchanger of the MYRRHA plant. The analysis focuses on evaluating the total pressure drop on the primary side for different mass flow rates of the primary coolant, deriving pressure loss coefficients as function of Re number as well as assessing the impact of the heat exchanger tube bundle support grids on the pressure drop. A preliminary assessment of global heat transfer characteristic of the PHX is also performed.