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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Deploying contrail forecasting service to reduce the impact of aviation on Environment

Chhajed, Tejashree Rakumar 03 May 2016 (has links) (PDF)
The principal objective of this thesis is to propose a Contrail forecasting Service for Aviation(ConSA) and a ConSA client to demonstrate the service. The subject is motivated by the fact that Contrails have a very harmful effect on the environment and it has been researched thoroughly by scientists. But still we do not have an infrastructure to include these researches in the Aviation industry. This thesis has been conducted at Airbus Defence and Space, Friedrichshafen, Germany. The first part of the thesis investigates the existence of contrails. The object of interest i.e. Contrails is caused by the passage of aeroplanes in ice-saturated areas. The algorithm which is used by the service is a part of the research conducted by Prof. Dr. Ulrich Schumann. The input dataset provided by Meteo France is a 4D weather cube. The algorithm computes a threshold temperature and ice supersaturation condition. When both of these conditions are satisfied Contrail formation is certain. In the second part we explain the architecture and solution used i.e. OGC (Open Geospatial Consortium) and LuciadLightspeed to develop Web Services to deploy contrail forecasting methods. Such an architecture fast forwards and eases the task of developer by having inbuilt methods and interfaces. The OGC web services infrastructure has defined web feature service and client interface which ease development of geoinformatics solutions.We also use certain standards like WXXM for exchange of contrail information which will be stated in this chapter. The third part is about the detailed implementation of the ConSA service and client. In this chapter we explain the service and client with uml diagrams to clarify the development concepts. The final part of the thesis explains the results of ConSA service and client, operational benefits of ConSA and concludes the thesis.
2

Impact on flight trajectory characteristics when avoiding the formation of persistent contrails for transatlantic flights

Yin, Feijia, Grewe, Volker, Frömming, Christine, Yamashita, Hiroshi 24 September 2020 (has links)
This paper studies the impacts on flight trajectories, such as lateral and vertical changes, when avoiding the formation of persistent contrails for transatlantic flights. A sophisticated Earth-System Model (EMAC) coupled with a flight routing submodel (AirTraf) and a contrail submodel (CONTRAIL) is used to optimize flight trajectories concerning the flight time and the flight distance through contrail forming regions (contrail distance). All the trajectories are calculated taking into account the effects of the actual and local meteorological parameters, e.g., wind, temperature, relative humidity, etc. A full-year simulation has been conducted based on a daily flight schedule of 103 transatlantic flights. The trade-off between the flight time and contrail distance shows a large daily variability, meaning for the same increase in flight time, the reduction in contrail distance varies from 20% to 80% depending on the daily meteorological situation. The results confirm that the overall changes in flight trajectories follow a seasonal cycle corresponding to the nature of the potential contrail coverage. In non-summer seasons, the southward and upward shifts of the trajectories are favorable to avoid the contrail formation. In summer, the northward and upward shifts are preferred. A partial mitigation strategy for up to 40% reduction in contrail distance can be achieved throughout all the seasons with a negligible increase in flight time (less than 2%), which represents a reasonable trade-off between flight time increase and contrail avoidance.
3

Aircraft Contrail Prediction for Commercial Flights / Förutsägning av flygplans kondensspår för kommersiella flygningar

Kundgol, Chirag January 2022 (has links)
The prediction of contrails have been studied since the 1930s primarily for militaryapplications. In present times, contrail avoidance strategies are gaining popularity insustainable aviation. In this project, the theory behind their formation, persistenceand the mitigation strategies are explored, studied and implemented.Several methods are evaluated in order to predict the critical temperature. Aircraftparameters are included in the prediction of contrails and implemented. This dynamicprogramming is contrasted against real case operational flight plans.The first implementation considers an operational flight plan for which contrails are pre-dicted along the trajectory. The second involves the prediction of contrails at the end ofthe vertical trajectory optimisation. The optimisation for contrail persistence avoidanceis also accomplished. Results show that contrail persistence can be avoided. / Förutsägelsen av kondensspår har studerats sedan 1930-talet, främst för militära tillämp-ningar. I nutid, strategier för undvikande av långvariga kondensspår ökar i popularitetinom hållbar flygning. I det här examensarbetet, utforskas och studeras teorin bakombildning, uthållighet och begränsningsstrategier för kondensspår för att sedan imple-menteras.Flera metoder evalueras för att förutsäga den kritiska temperaturen. Flygplansparame-trar är inkluderade och implementerade i förutsägelsen av kondesspår. Den dynamiskaprogrammeringen jämförs mot verkliga operativa färdplaner.Den första implementeringen avser en operativ färdplan för vilken kondensspår förut-spås längs banan. Den andra implementeringen involverar förutsägelse av kondensspåri slutet av den vertikala banoptimeringen. Optimeringen med avseende på långvarigakondensspår genomförs också. Resultaten visar att långvariga kondensspår kan und-vikas.
4

Simulation aux grandes échelles de traînées de condensation dans un milieu atmosphérique stratifié et turbulent.

Picot, Joris 21 February 2013 (has links) (PDF)
La prise en compte des traînées de condensations (contrails) dans les modèles de grande échelle requiert une paramétrisation. Cependant, les données actuelles sont insuffisantes pour cette paramétrisation. La simulation numérique détaillée d'un contrail complète les données et elle contribue à mieux définir ces paramétrisations. Les études des aéronefs ont mis en évidence le rôle de la turbulence atmosphérique dans la dynamique des tourbillons de sillage. Pourtant, la majorité des simulations numériques de contrails réalisées à ce jour utilisent une représentation simplifiée et paramétrée de cette turbulence, plutôt que de la résoudre explicitement. Le travail réalisé ici consiste à mettre en place une simulation de contrail avec une résolution tridimensionnelle de la turbulence atmosphérique. Dans un premier temps, une méthode de forçage stochastique a été mise en place pour engendrer des écoulements turbulents dans un milieu stratifié, et on montre la capacité de cette méthode à reproduire la turbulence de l'atmosphère. Dans un second temps, une simulation de contrail a été mise en place en utilisant la turbulence atmosphérique engendrée précédemment. Les effets du niveaux de turbulence, de la température et de la saturation en vapeur d'eau sur le contrail sont étudiés pour les quatre premières minutes : la turbulence contrôle la destruction des tourbillons de sillage, alors que la saturation et la température contrôlent la persistance et le taux de formation de glace. Les propriétés microphysiques et optiques obtenues sont en accord avec les observations et des lois sont proposées pour adapter ces propriétés aux paramétrisations des modèles de grande échelle.
5

Deploying contrail forecasting service to reduce the impact of aviation on Environment: Deploying contrail forecasting service to reduce the impact of aviation onEnvironment

Chhajed, Tejashree Rakumar 24 March 2016 (has links)
The principal objective of this thesis is to propose a Contrail forecasting Service for Aviation(ConSA) and a ConSA client to demonstrate the service. The subject is motivated by the fact that Contrails have a very harmful effect on the environment and it has been researched thoroughly by scientists. But still we do not have an infrastructure to include these researches in the Aviation industry. This thesis has been conducted at Airbus Defence and Space, Friedrichshafen, Germany. The first part of the thesis investigates the existence of contrails. The object of interest i.e. Contrails is caused by the passage of aeroplanes in ice-saturated areas. The algorithm which is used by the service is a part of the research conducted by Prof. Dr. Ulrich Schumann. The input dataset provided by Meteo France is a 4D weather cube. The algorithm computes a threshold temperature and ice supersaturation condition. When both of these conditions are satisfied Contrail formation is certain. In the second part we explain the architecture and solution used i.e. OGC (Open Geospatial Consortium) and LuciadLightspeed to develop Web Services to deploy contrail forecasting methods. Such an architecture fast forwards and eases the task of developer by having inbuilt methods and interfaces. The OGC web services infrastructure has defined web feature service and client interface which ease development of geoinformatics solutions.We also use certain standards like WXXM for exchange of contrail information which will be stated in this chapter. The third part is about the detailed implementation of the ConSA service and client. In this chapter we explain the service and client with uml diagrams to clarify the development concepts. The final part of the thesis explains the results of ConSA service and client, operational benefits of ConSA and concludes the thesis.

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