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The objective of this paper is to present a numerical method to rank thick ice shapes for aircraft by comparing the ice accretion effects for different icing scenarios in order to determine the more critical ice shape. This ranking allows limiting the demonstration of the aerodynamic characteristics of the aircraft in iced condition during certification to a reduced number of ice shapes. The usage of this numerical method gives more flexibility to the determination of the critical ice shapes, as it is not dependent of the availability of physical test vehicles and/or facilities. The simulation strategy is built on the Lattice Boltzmann Method (LBM) and is validated based on a representative test case, both in terms of aircraft geometry and ice shapes. Validation against existing experimental results shows the method exhibits an adequate level of reliability for the ranking of thick ice shapes.

The intent of this paper is to provide a general overview of the main engineering and test activities conducted in order to support A350XWB Ice and Rain Protection Systems certification. Several means of compliance have been used to demonstrate compliance with applicable Certification Basis (CS 25 at Amendment 8 + CS 25.795 at Amendment 9, FAR 25 up to Amendment 129) and Environmental protection requirements. The EASA Type Certificate for the A350XWB was received the 30th September 2014 after 7 years of development and verification that the design performs as required, with five A350XWB test aircraft accumulating more than 2600 flight test hours and over 600 flights. The flight tests were performed in dry air and measured natural icing conditions to demonstrate the performance of all ice and rain protection systems and to support the compliance demonstration with CS 25.1419 and CS25.21g.

The aim of this work is to characterize the formation of metal pick-ups onto Automotive brake pads, that can lead to major wear problems for the friction material and for the rotors. The characterization of these metal pick-ups has been obtained by means of microscopy techniques (optical microscope and SEM analysis), by X-ray diffraction and thermal analysis, while it has been tried to evaluate the influence of morphological and compositional parameters (like amount of lubricants and of organic compounds) of the pad on the pick-ups formation by performing “true-scale” simulations following specific procedures.

The type of pump (lobe, centrifugal, or piston) used in a circulation system determines the degree of mechanical and shear degradation inflicted upon the pigments present in a waterborne metallic paint. The visible effect of degrading the performance of a metallic paint is the extreme variation encountered in the appearance of the resulting automotive finish. We have determined through multiple angle spectrophotometry that lobe and centrifugal pumps initially cause a similar amount of degradation to the two-tone effect exhibited by a metallic finish. The degradation effect associated with a lobe pump was observed to dramatically increase with extended usage of the pump. Piston pumps were discovered to cause the least amount of paint degradation. A centrifugal pump having open impellers performed similar to a centrifugal pump with closed impellers.