Tesis doctoral de Xavier Prats Menéndez
Despite the substantial reduction of the emitted aircraft noise in the last decades, the noise impact on communities located near airports is a problem that still lingers. Containing the sound generated by aircraft operations, while meeting the increasing demand for aircraft transportation, is one of the major challenges that airport authorities, air traffic service providers and aircraft operators may deal with. Aircraft noise can be reduced by improving the aerodynamics of the aircraft, the engine noise emissions but also in designing new optimised flight procedures. These procedures, are generally called noise abatement procedures (nap) and may include preferential routings (in order to avoid populated areas) and also schedule optimised vertical flight path profiles. present noise abatement procedures are far from being optimal in regards to minimising noise nuisances. In general, their optimisation is not possible due to the limitations of navigation methods, current avionic equipments and the complexity present at some terminal airspaces. Moreover, nap are often designed manually by a group of experts and several iterations are needed. However, in the forthcoming years, new avionic systems and new air traffic management concepts are expected to significantly improve the design of flight procedures. This will make them more flexible, and therefore will allow them to be more environmental friendly. Furthermore, in the few cases where nap are optimised, an acoustical metric is usually used when building up the different optimisation functions. Therefore, the actual noise annoyance is not taken into account in the optimisation process. The annoyance is a subjective, complex and context-dependent concept. Even if sophisticated noise annoyance models are already available today, their integration into an trajectory optimisation framework is still something to be further explored. this dissertation is mainly focused on the fact that those precise and more flexible trajectories will enable the definition of optimal flight procedures regarding the noise annoyance impact, especially in the arrival and departure phases of flights. In addition, one can conceive a situation where these kinds of procedures can be designed automatically or semi-automatically by an expert system, based on optimisation techniques and approximate reasoning. This would serve as a decision making tool for airspace planners and procedure designers. a complete framework for computing optimal nap is developed in this work. This includes a set of nonlinear models which take into account aircraft dynamics, trajectory constraints and objective functions. The noise annoyance is modelled by using fuzzy logic techniques in function of the perceived maximum sound level, the hour of the day and the type of over-flown zone. The problem tackled, formally identified and formulated as a multi-criteria optimal control problem, uses a direct transcription method to transform it into a non linear programming problem. Then, an assessment of different multi-objective optimisation techniques is presented. Among these techniques, scalarisation methods are identified as the most widely used methodologies in the present day literature. Yet, in this dissertation several alternative techniques are explored in order to overcome some known drawbacks of this technique. In this context, lexicographic, hierarchical, egalitarian (or min-max) and goal optimisation strategies are presented and tested. From this analysis some conclusions arise allowing us to take advantage of the best features of each optimisation technique aimed at building a final compound multi-objective optimisation strategy. Finally, this strategy is applied successfully to a complex and real scenario, where the east departures of runway 02 at the airport of girona (catalonia, spain) are optimised. Two aircraft types are simulated at different periods of the day obtaining different optimal trajectories.
Datos académicos de la tesis doctoral «Contributions to the optimisation of aircraft noise abatement procedures«
- Título de la tesis: Contributions to the optimisation of aircraft noise abatement procedures
- Autor: Xavier Prats Menéndez
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 29/01/2010
Dirección y tribunal
- Director de la tesis
- Joseba Quevedo Casin
- Tribunal
- Presidente del tribunal: Francisco javier Sáez nieto
- joel Bordeneuve guibé (vocal)
- nicolas Barnier (vocal)
- hendrikus g. Visser (vocal)