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There is a worldwide trend for the evaluation of internal thermal comfort in aircraft cabins. Even nowadays one of the major difficulties found is the development and application of a standardized index of internal thermal comfort evaluation in the complex environment of a passenger cabin. The objective of this paper is the CFD model description to evaluate the thermal environment in an aircraft passenger cabin and its results. For this, a digital thermal manikin was developed. Experimental and numerical global heat transfer coefficients were compared. Precision of less than 10% was achieved. In this evaluation five turbulent models were tested. Latter, two numerically calibrated manikins were put into a typical cabin. As a comfort index it was used the equivalent temperature for eighteen body segments. A study of the manikin equivalent temperatures with the aircraft on the ground, in cruise and with low ventilation conditions is presented.

The free-fall operation comprises a redundant, dissimilar and independent mechanically operated method of extending airplane landing gear due to a main hydraulic system failure or an electrical system malfunction. However, the emergency extension operation system design is not unique and spring-assisted, auxiliary hydraulics-assisted or even pneumatics-assisted landing gear free-fall design can be found in different airplanes. This paper aims at describing the model simulation and the optimization of certain parameters related to the associated hydraulic system, for emergency operation condition, in a non-assisted system configuration comprising simple extension by gravity.

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.

The main function of the brake system is to decelerate the aircraft on the ground, a function that is directly linked to the safety of the aircraft's operation. Furthermore, brake performance has a direct impact on the weight that can be carried and therefore on an airline's operating cost. Therefore, it is very important to develop an optimized brake system to maximize braking performance in various runway conditions. Modeling and simulation are one of the ways to optimize this dimensioning in addition to reducing development costs. The objective of this paper is to present a modeling and simulation methodology in order to predict the behavior of the aircraft integrated with the brake system in the different scenarios of use of the brakes. This methodology allows evaluating the performance of the integrated system, as well as mitigating possible problems during system development.

A new computational method was developed that enables preliminary tuning of Auto Pilot System internal parameters based on time response analysis of the aircraft and its auto pilot. This method main purpose is to reduce flight tests during Auto Pilot calibration procedure.

The main topic in this report is the discussion of the advantages of using software that is easy and intuitive for operational planning and dispatch of regional transport aircraft.

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.