Computational analysis and design of an aerofoil with morphing tail for improved aerodynamic performance in transonic regime

This article focuses on the aerodynamic design of a morphing aerofoil at cruise conditions using computational fluid dynamics (CFD). The morphing aerofoil has been analysed at a Mach number of 0.8 and Reynolds number of 3×106 , which represents the transonic cruise speed of a commercial aircraft. In this research, the NACA0012 aerofoil has been identified as the baseline aerofoil where the analysis has been performed under steady conditions at a range of angles of attack between 0∘ and 3.86∘ . The performance of the baseline case has been compared to the morphing aerofoil for different morphing deflections ( wte/c=[0.005−0.1] ) and start of the morphing locations ( xs/c=[0.65−0.80] ). Further, the location of the shock wave on the upper surface has also been investigated due to concerns about the structural integrity of the morphing part of the aerofoil. Based upon this investigation, a most favourable morphed geometry has been presented that offers both, a significant increase in the lift-to-drag ratio against its un-morphed counterpart and has a shock location upstream of the start of the morphing part

Permeability analysis in bisized porous media: wall effect between particles of different size

The permeability of binary packings of glass beads with different size ratio – 13.3, 20, and 26.7, was investigated. In the Kozeny–Carman equation, the dependence of the tortuosity τ on the mixture porosity ε(xD) was described according to τ = 1/εn for different volume fraction of large particles in the mixture, xD. Obtained data on packing permeability shows that the parameter n is a function of the volume fraction and particle size ratio, with values between 0.5 and 0.4. This can be explained by the wall effect resulting from the arrangement of the small particles occurring near the large particle surface. A model taking in account this effect was suggested that can be useful in the characterization of transport phenomena in granular beds as well as in engineering applications.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BPD/18128/2004; Project POCI_EQU_58337/2004

Les marchandises transportées par bateau

Mauret-Cribellier Valérie. Les marchandises transportées par bateau. In: Le Cher. Histoire et archéologie d’un cours d’eau. Tours : Fédération pour l'édition de la Revue archéologique du Centre de la France, 2013. pp. 132-137. (Supplément à la Revue archéologique du centre de la France, 43