In this master thesis the results of convective boiling simulations using the ANSYS Fluent code are presented. The two-phase flow is described using the Eulerian two-fluid model framework, that is based on the phase averaged equations. Simulations are done with consideration of turbulent momentum, heat and mass transfer between the phases. For wall boiling the heat partitioning model is used. Bubble sizes are modelled using the population balance model that accounts for bubble growth and shrinkage due to evaporation and condensation, coalescence due to collisions and breakage due to turbulence. Simulation results are compared with the experimental results of three different DEBORA cases at different operating conditions. Distributions of main two-phase flow parameters such as void fraction, the average bubble size and the liquid temperature are compared. On one of the cases, the population balance model is studied in more detail. The influence of bubble classes, the liquid temperature, the wall temperate and the effect of heat flux partitioning model is analysed.
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