Tham khảo tài liệu 'wind tunnels part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Rebuilding and Analysis of a SCIROCCO PWT Test on a Large TPS Demonstrator 61 It must be underlined that these gaps have been modelled with sharp edges a measure of local curvature radii was not available therefore results in terms of heat flux peaks are conservative. Moreover the bow shock wave surface has been properly fitted. In order to minimize the numerical instabilities that propagate from the shock wave towards the stagnation region the carbuncle phenomenon it is important to align as much as possible the grid lines to the shock. Grid characteristics are listed in Tab. 1 Anmin being the minimum spacing normal to the wall at the stagnation point and AR the corresponding aspect ratio. Three grid levels have been adopted in order to assure grid convergence of results as it will be shown in Section . Grid Level Cells coarse 32468 medium 259744 fine 2077952 ttỉira AR 7 1 O 6tn 2500 2 1 O 6tn 4050 1 10 s tn 4410 Table 1. Computational grid characteristics Fig. 4. Block decomposition Fig. 5. Three dimensional computational grid 62 Wind Tunnels Fig. 6. Detail of the top frame Fig. 7. Gap between panels and frame left and T gap right 5. Pre Test CFD activity In this section CFD three dimensional results of the flow field computed around the test article are shown and deeply analyzed for the PWT condition selected during the test design phase Rufolo et al. 2008 . Ps mbara and Qs 2070 kW m2. Subsequently grid convergence of results will be shown in Section and an assessment of the uncertainty level linked to both design and testing phases will be presented in Section . Three-dimensional results and test requirements verification Three-dimensional computations on the full test article configuration have been performed with the aim at verifying the test requirements fulfilment with the PWT condition defined. Moreover information about flow features presence of vortex structures separation and reattachment lines overheatings induced by the gaps .
