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An advanced computational and experimental analysis has been performed upon a conventional aircraft wing with two outboard morphing partitions that are variable in twist and dihedral angles. Results are generated with the intention of drawing meaningful comparisons with initial trends in aerodynamic and structural efficiency that have been observed in previous optimization studies. Computational results are obtained with the DLR , German Aerospace Center TAU computational fluid dynamics code, both for an aircraft wing in high-speed flight and for a wing modeled at low speed with wind-tunnel wall constraints. An experimental testing has been performed at the University of Bristol 7 x 5 ft low-speed wind tunnel. An outer-twist variation of ±3 deg and dihedral angles from planar up to 90 deg C-wing geometries are tested for a range of incidence angles. Results demonstrate varying levels of agreement between each form of analysis method, and offer insight into the aerodynamic and structural tradeoff required to select an optimal configuration. [ABSTRACT FROM AUTHOR]

Proportionally large relative radial clearances can be found within the rear stages of multistage axial compressors of gas turbines and aero engines, with significant impact on their efficiency. A new three-dimensional design for cantilevered stators in axial com-pressors is presented, with the aim of improving the overall efficiency and losses of rear stage vanes with large relative hub clearances. The new vane design comprises an uncon-ventional dihedral, with special consideration to reduce the losses caused by the hub clearance vortex. The design was tested in a 4-stage low speed axial research compressor under rear stage conditions. The results are compared to the nominal design to validate the reduction of hub clearance losses and blockage. For both designs, the hub clearances over the third and fourth stator were varied from 1.5% up to 6.0% of span. Overall per-formance data and flow field traverses upstream and downstream of stator 3 and rotor 4 will be presented in this article in comparison with 3D CFD results [ABSTRACT FROM AUTHOR]