Klein, ChristineWinzig, Manuel2023-07-272023-07-272020https://ri.itba.edu.ar/handle/123456789/4219Tesis Energía y Ambiente (maestría) - Instituto Tecnológico de Buenos Aires - Karlsruher Institut für Technologie, Karlsruhe, 2020This work contributes to the development of the future fusion reactor DEMO. It investigates the cooling of the first wall blankets by rib structured cooling channels. For this purpose, RANS simulations using the 𝑘 − 𝜔 − 𝑆𝑆𝑇 model and the Reynolds Stress Model as well as Large Eddy Simulation were carried out on a channel with V-shaped ribs on one side at a Reynolds number of 𝑅𝑒 = 1.56 ⋅ 10 As a working fluid helium was used at an operating pressure of 𝑝 = 8 𝑀𝑃𝑎. The relative roughness of the channel was 𝑒⁄𝐷ℎ = 0.0461 and the rib pitch was 𝑝⁄𝑒 = 10. The focus of the analysis of the results has been on heat transfer quantities, pressure loss and flow patterns. It was shown that the rib induced vortical structures that were associated with a large increase in heat transfer downstream of the rib but also caused a heat transfer deterioration directly behind it. The comparison between the simulations has shown that the 𝑘 − 𝜔 − 𝑆𝑆𝑇 model resolves well the magnitude of the averaged heat transfer but fails to reproduce the flow patterns and friction factor accurately when compared to the Large Eddy Simulation. On the other side, the Reynolds Stress Model showed better accuracy resolving the flow patterns and friction factor but strongly underpredicts the heat transfer for the given case. Additionally, the results of the Large Eddy simulation have been compared to previous simulation results that have been conducted on a smooth and a rib structured channel with 𝑒 = 0.9 𝑚𝑚. It was shown that reducing the rib height led to a slight decrease in heat transfer on the rib structured side but also reduced the pressure loss significantly.enREACTORES NUCLEARESENERGIA NUCLEARFUSION NUCLEARTesis de Maestría