Experimental and numerical investigations of heat transfer in the first wall of Helium-Cooled-Pebble-Bed Test Blanket Module—Part 2: Presentation of results

Engineering Design of the European DEMO HCPB Breeding Blanket Breeder Zone Mockup

“…where, Re is Reynolds number, e sand-grain roughness, D h the hydraulic diameter, f Darcy friction factor. 0 ≤ e + < 5 Hydraulically smooth regime (7) 5 ≤ e + < 70 Transition regime (8) e + ≥ 70 Fully rough regime (9) Three different surface roughness conditions are proposed to be tested following the above-mentioned flow regime classifications. For the hydraulically smooth regime, the normally manufactured surface with an Rz of about 10 µm, where Rz is the difference between the tallest peak and the deepest valley in the surface.…”

“…As we are consolidating the concept, there is an increasing need to proceed to qualify the blanket concept through testing. A series of design and experimental activities for testing the components of the HCPB blanket were conducted in the last decade [7][8][9][10][11][12]. The HETRA experimental campaigns on the helium-cooled First Wall of the HCPB test blanket module (TBM) were conducted to investigate the thermal hydraulic (heat removal and pressure drop) effectiveness of the surface roughness in the First Wall channels in 8 MPa pressure and 300 • C temperature conditions [7].…”

“…A series of design and experimental activities for testing the components of the HCPB blanket were conducted in the last decade [7][8][9][10][11][12]. The HETRA experimental campaigns on the helium-cooled First Wall of the HCPB test blanket module (TBM) were conducted to investigate the thermal hydraulic (heat removal and pressure drop) effectiveness of the surface roughness in the First Wall channels in 8 MPa pressure and 300 • C temperature conditions [7]. The mass flow distribution of the HCPB TBM coolant system were performed in the GRICAMAN experimental facility [8].…”

Transient analyses on the cooling channels of the DEMO HCPB blanket concept under accidental conditions

“…For the simulations, the k-SST model was used, which was proved suitable for the studied cases [8]. For the mesh sensitivity, two meshes having a near-wall wall distance y+ of 7 and 14, respectively, were tested; the calculations results show essentially no difference.…”