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In this paper a cold soak fuel frost modeling for an aircraft wing tank is presented. Numerical prediction is compared with experimental data and a qualitative verification for the frost formation and melting is also shown. The numerical simulation showed good agreement with experimental observations. The model was used to define, through a Monte Carlo analysis, two different frost formations whose impact on aircraft handling was evaluated by flight tests using representative grits.

This paper presents an aerodynamic degradation study of an iced airfoil, using the Lattice Boltzmann approach with the commercial software PowerFLOW. Three-dimensional numerical simulations were performed with an extruded constant section of the GLC-305 airfoil with a leading-edge double-horn ice shape using periodic boundary conditions. The freestream Reynolds number, based on the chord, is 3.5 million and the Mach number is 0.12. An extensive comparison of the main flow features with experimental data is performed, including aerodynamic coefficients, pressure coefficient distributions, velocity and turbulence contours along with its profiles at several positions, and stagnation streamlines. The drag coefficient agrees well with experiments, in spite of a small shift. Two different wind tunnel measurements, using different measurement techniques, were compared to the CFD results, which mostly stayed in between the experimental data.

A problem of interest of the aeronautical industry is the positioning of electronic equipment in racks and the associated ventilation system project to guarantee the equipment operational conditions. The relevance of the proper operation of electronic equipment increases considerably when high economical costs, performance reduction and safety are involved. The appropriate operational conditions of the electronic components happen when the working temperature of the equipment installed in the rack is inside a safety project temperature margin. Therefore, the analysis and modelling of heat transfer processes for aircraft rack design becomes mandatory. This paper presents a parametric study considering volumetric and superficial heat generation in electronic equipment within racks in an aircraft. Simulations were performed using the commercial CFD Fluent code and results were compared to experimental data.

Nowadays CFD analysis including virtual manikins is vastly applied to evaluate thermal comfort inside different working environments, such as buildings cars and aircrafts. Inside aircraft cabins, added to the numerical challenges due to geometrical complexity, the available subjective responses used to judge occupant local thermal comfort are usually based on buildings and cars experiments [1]. In the present paper however, it is applied an aircraft based subjective responses to evaluate thermal comfort which was specifically developed using regional jet mock-up experiments. The evaluation for the two approaches will be compared providing insight of the main differences.

An important issue regarding landing performance is the reference speed which determines the approved fields lengths in which a landing can take place. A critical scenario is the accumulation of ice during the holding phase followed by descent, approach and landing. The effect of icing in the landing configuration, with the high-lift devices deployed, is relevant and should be anticipated during the early design phases by simulation. Due to the complex behaviour of the flowfield, 3D CFD methods has been used by several manufacturers but that leads to a high computational cost which might be too intensive for the preliminary design phase.