A Comparison of Two-Phase Computational Fluid Dynamics Codes Applied to the ITER First Wall Hypervapotron

Numerical investigation of collector cooling for a 1 MW ITER gyrotron operated with vertical sweeping

“…Indeed, in the last years various CFD tools have been used to assess theoretically the HV fluid-dynamics and heat transfer mechanisms [8][9][10][11][12]. These works referred to a flat HV geometry with rectangular flow channel, operated under steady-state heat load conditions, which is of particular interest for plasma-facing components and/or ion beam dumps for neutral beam injectors, whereas here we investigate for the first time with CFD the gyrotron collector problem, characterized by an annular geometry (which justifies the use of 2D models, instead of 3D needed in the case of the flat geometry), subject to transient heat load due to the sweeping of the spent electron beam on the collector surface.…”

CFD analysis of flow boiling in the ITER first wall

“…Then, ∼1 Mcells are a good compromise between reasonable grid-independence of the solution and computational cost. This size of the mesh is also comparable to that chosen in previously published works on the same subject [6,7]. For the hypervapotron, we kept the same average cell size (∼0.5 mm), but we used tetrahedral cells because of the more complex flow geometry.…”

“…Overall, there are six user provided input parameters. Here we use the values suggested in [6,7], see Table 1, determined best-fitting the experimental database.…”

“…To the best of our knowledge, this is the first time that the Rohsenow and BR models are critically compared for an ITER-relevant application. Also, we are not aware of an implementation of the BR model in FLUENT so far and, indeed, previous applications of FLUENT to ITER-relevant boiling problems met only limited success [6]. Fig.…”

“…In order to predict the system performance, a dedicated thermal hydraulic analysis has to be conducted, and several papers have been devoted during the last few years to this task on different geometries foreseen for the ITER first wall [3][4][5][6][7].…”