[ES] En el presente trabajo se explora posibles soluciones a dos hechos correlacionados que podrían comprometer hasta cierto punto nuestro futuro. Por un lado, el crecimiento de la flota de aeronaves pequeñas en los próximos años, ya sean tripuladas o no, es una realidad. El acceso a estas aeronaves por parte de un público cada vez más mayoritario crece año a año y, al mismo tiempo, los fabricantes adaptan sus aeronaves a misiones que hace unos años no éramos capaces de contemplar. Por otro lado, y por desgracia, el cambio climático también es una realidad que no solo compromete nuestro futuro, sino también nuestro presente. Hoy en día la alerta climática es y debe ser elevada, y si no encontramos soluciones que ayuden a paliar este problema, la vida en el planeta podría cambiar irremediablemente para peor. Ambos hechos se encuentran implícitamente relacionados. La fabricación y operación de vehículos contribuye notablemente a aumentar la huella de carbono. Por lo tanto, el aumento de flota en los próximos años puede tener un impacto notablemente negativo en las emisiones contaminantes y gases de efecto invernadero globales. Es por ello por lo que organismos oficiales y sectores de desarrollo científico y tecnológico impulsan la investigación de posibles soluciones. Este trabajo intenta poner su grano de arena para minimizar este problema común. Se propone la utilización de múltiples tecnologías con el objetivo de disminuir el combustible requerido por aeronaves de 25kg al despegue, y de esta forma, disminuir las emisiones asociadas a su operación. Las tecnologías aplicadas son la hibridación eléctrica en serie, la propulsión eléctrica distribuida y la ingestión de capa límite. Por separado, estas tecnologías han demostrado múltiples ventajas, especialmente en términos de mejora propulsiva y aerodinámica de las aeronaves, lo que repercute directamente en el consumo de combustible. Sin embargo, este trabajo propone la utilización simultánea de todas ellas con el objetivo de disminuir aún más el consumo de combustible y, por tanto, las emisiones contaminantes y gases de efecto invernadero. Para ello, tras estas páginas se eligen los parámetros principales de esta aeronave y se acompaña de un exhaustivo análisis del comportamiento fluidodinámico. Con la comprensión de su comportamiento, es posible optimizar la selección de sus componentes, de forma que se obtienen mejoras importantes en el consumo de combustible. Este ahorro de combustible se muestra en comparación con aeronaves similares en tamaño y peso, pero que no incluyen estas tecnologías, logrando para un mismo alcance un ahorro del 16% del peso del combustible. La realización de este trabajo se centra en el empleo de herramientas computacionales apoyándose sobre todo en la dinámica de fluidos computacional (CFD). Esta herramienta principal se verá complementada con el uso de descomposición modal para realizar los análisis y de la creación de una base de datos que ayude a crear modelos rápidos útiles en futuros diseños preliminares y conceptuales de aeronaves de este tipo. / [CA] En aquest treball s'exploren possibles solucions a dos fets correlacionats que podrien comprometre d'alguna manera el nostre futur. Per un costat, el creixement de la flota d'aeronaus de xicoteta dimensió en el futur, tant tripulades com no tripulades, és una realitat. L'accés a aquestes aeronaus per part d'un públic cada cop més majoritari creix any rere any i, al mateix temps, els fabricants adapten les aeronaus a feines que anys enrere no eren capaços d'assolir. Per l'altre costat, malauradament, el canvi climàtic és un fet que compromet tant el nostre futur com el nostre present. Hui en dia l'alerta climàtica és elevada i, si no trobem solucions per a pal·liar aquest problema la vida al nostre planeta, podria canviar irremeiablement a pitjor. Ambdós fets es troben implícitament relacionats. La fabricació i l'operació de vehicles contribueix notablement a augmentar l'empremta de carboni. Per tant, l'increment de flota en els pròxims anys pot tindre un efecte negatiu molt notable en les emissions contaminants i gasos d'efecte hivernacle globals. És per això que organismes oficials i sectors de desenvolupament científic i tecnològic impulsen la investigació de possibles solucions. Aquest treball intenta aportar el seu granet de sorra per minimitzar aquest problema comú. Es proposa la utilització de múltiples tecnologies amb l'objectiu de reduir el combustible emprat per aeronaus de fins a 25kg i, per tant, disminuir les emissions associades a la seua operació. Les tecnologies aplicades són la hibridació elèctrica en sèrie, la propulsió elèctrica distribuïda i la ingestió de capa límit. Separadament, aquestes tecnologies han demostrat múltiples avantatges, especialment en termes de millora propulsiva i aerodinàmica de les aeronaus, repercutint directament en el consum de combustible. No obstant, aquest treball proposa la utilització simultània de totes elles amb l'objectiu de reduir encara més el consum de combustible i, per tant, les emissions contaminants i gasos d'efecte hivernacle. Per fer-ho, en les darreres pàgines es trien els paràmetres principals de l'aeronau i s'acompanyen d'una exhaustiva anàlisi del comportament de la dinàmica de fluids. Comprenent el seu comportament, és possible optimitzar la selecció dels seus components, de manera que s'obtenen millores importants en el consum de combustible. L'estalvi de combustible es mostra en comparació amb aeronaus similars en mida i pes, però que no inclouen aquestes tecnologies, aconseguint per a un mínim abast un estalvi del 16% del pes del combustible. La realització d'aquest treball es centra en l'ús d'eines computacionals recolzant-se sobretot en la dinàmica de fluids computacional (CFD). Aquesta eina principal es veurà complementada amb l'ús de descomposició modal per a elaborar les anàlisis i de la creació d'una base de dades que ajude a crear models ràpids i útils en futurs dissenys conceptuals i preliminars d'aeronaus d'aquest tipus. / [EN] The present work explores possible solutions to two correlated events that could compromise our future to some extent. On the one hand, the growth of the fleet of small aircraft in the coming years, whether manned or not, is a reality. Access to these aircraft by an increasing majority of the public grows year after year and at the same time, manufacturers adapt their aircraft to missions that we could not contemplate a few years ago. On the other hand, and unfortunately, climate change is also a reality that compromises not only our future but also our present. Today the climate alert is and must be elevated. If we do not find solutions that help alleviate this problem, life on the planet could irremediably change for the worse. Both facts are implicitly related. The manufacture and operation of vehicles contribute significantly to increasing the carbon footprint, so the increase in the fleet in the coming years may have an extremely negative impact on global polluting and greenhouse gas emissions. That is why official organizations and scientific and technological development sectors promote research for possible solutions. This work tries to do its bit to minimize this common problem. Multiple technologies are proposed to reduce the fuel required by 25kg aircraft at takeoff and, thus, reduce the emissions associated with their operation. The applied technologies are electric series hybridization, distributed electric propulsion, and boundary layer ingestion. Separately, these technologies have shown multiple advantages, especially in terms of improving aircraft propulsion and aerodynamics, which directly affects fuel consumption. Nevertheless, this work proposes the simultaneous use of all of them to reduce fuel consumption further and, therefore, polluting and greenhouse gas emissions. To do this, after these pages, the main parameters of this aircraft are chosen and accompanied by an exhaustive analysis of the fluid dynamic behavior. With an understanding of its behavior, it is possible to optimize its components' selection so that significant fuel consumption improvements are obtained. This fuel saving is shown in comparison with similar aircraft in size and weight, but that does not include these technologies, achieving a saving of 16% of fuel weight for the same range. This work's conduction focuses on employing computational tools mainly based on computational fluid dynamics (CFD). This primary tool will be complemented by the use of modal decomposition to carry out the analyses, and the creation of a database that will help create quick models useful in future conceptual and preliminary designs of this type of aircraft. / The respondent would like to acknowledge the financial support received through contract FPI-UPV PREDOCFD/19 of Subprograma 2 of Universitat Politècnica de València / Varela Martínez, P. (2023). On the Analysis and Design of Series Hybrid Distributed Electric Propulsion with Boundary Layer Ingestion of Remotely Piloted Aircraft [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/192805

In the last half century, the aerospace industry has seen a dramatic paradigm shift from a focus on performance-at-any-cost to product economics and value. The steady increase in product requirements, complexity and global competition has driven aircraft manufacturers to seek broad portfolios of advanced technologies. The development costs and cycle times of these technologies vary widely, and the resulting design environment is one where decisions must be made under substantial uncertainty. Modeling and simulation have recently become the standard practice for addressing these issues; detailed simulations and explorations of candidate future states of these systems help reduce a complex design problem into a comprehensible, manageable form where decision factors are prioritized. While there are still fundamental criticisms about using modeling and simulation, the emerging challenge becomes ``How do you best configure uncertainty analyses and the information they produce to address real world problems?” One such analysis approach was developed in this thesis by structuring the input, models, and output to answer questions about the risk and economic impact of technology decisions in future aircraft programs. Unlike other methods, this method placed emphasis on the uncertainty in the cumulative cashflow space as the integrator of economic viability. From this perspective, it then focused on exploration of the design and technology space to tailor the business case and its associated risk in the cash flow dimension. The methodology is called CASSANDRA and is intended to be executed by a program manager of a manufacturer working of the development of future concepts. The program manager has the ability to control design elements as well as the new technology allocation on that aircraft. She is also responsible for the elicitation of the uncertainty in those dimensions within control as well as the external scenarios (that are out of program control). The methodology was applied on a future single-aisle 150 passenger aircraft design. The overall methodology is compared to existing approaches and is shown to identify more economically robust design decisions under a set of at-risk program scenarios. Additionally, a set of metrics in the uncertain cumulative cashflow space were developed to assist the methodology user in the identification, evaluation, and selection of design and technology. These metrics are compared to alternate approaches and are shown to better identify risk efficient design and technology selections. At the modeling level, an approach is given to estimate the production quantity based on an enhanced Overall Evaluation Criterion method that captures the competitive advantage of the aircraft design. This model was needed as the assumption of production quantity is highly influential to the business case risk. Finally, the research explored the capacity to generate risk mitigation strategies in to two analysis configurations: when available data and simulation capacity are abundant, and when they are sparse or incomplete. The first configuration leverages structured filtration of Monte Carlo simulation results. The allocation of design and technology risk is then identified on the Pareto Frontier. The second configuration identifies the direction of robust risk mitigation based on the available data and limited simulation ability. It leverages a linearized approximation of the cashflow metrics and identifies the direction of allocation using the Jacobian matrix and its inversion.

The study is conducted to determine practical modelling and simulation techniques to perform dynamic stability and performance analysis on a 3 Degrees of freedom aircraft model using a Modelica-based commercial tool called Modelon Impact. This study is based on a conceptual aircraft model where in-depth details about the aircraft configuration are unknown and the aim is to determine a suitable model that can capture the longitudinal dynamics and aerodynamic constraints of the aircraft during the conceptual design phase. Requirements include short execution time, easy model development, and minimal data requirements. Therefore, this thesis aims at developing plant and control architectures in  Modelon Impact which can be utilized for the rapid development of aircraft concepts with adequate fidelity in a longitudinal mission-based tracking environment. In a conceptual aircraft design environment, to identify a suitable methodology that mitigates the limitations of a traditional feedback controller, two methodologies are considered for comparison: Sequential DAE resolution (SDR) and Dynamic inversion (DI) control which is discussed from an object-oriented aircraft model. The advantages and shortcomings of each of the models discussed above are compared by conducting several experiments in increasing order of longitudinal mission complexity, and the most appropriate model among the two for a conceptual stage of aircraft design development is ascertained. The two methodologies discussed are compared for their level of complexity, code structure, readability, and ease of usability.

This master’s thesis deal with design of EV-55 Outback airplane with pressurized cabin. In this thesis are given common principles and requirements of regulations on construction pressurized cabin. A necessary fuselage modifications and fuselage construction are included. Also construction and build up of air-conditioning system and emergency oxygen system are included. Some parts of this thesis are about weight and balance, definition of pressurized cabin load, simple stability analysis and basic flight performance calculation. At the end of this master’s thesis a result of weight and flight performances are compared with analogous airplanes by other producers.

Purpose - This thesis presents a comparison of aircraft design concepts to identify the superior propulsion system model among turbo-hydraulic, turbo-electric and classic jet propulsion with respect to Direct Operating Costs (DOC), environmental impact and fuel burn. --- Approach - A simple aircraft model was designed based on the Top-Level Aircraft Requirements of the Airbus A320 passenger aircraft, and novel engine concepts were integrated to establish new models. Numerous types of propulsion system configurations were created by varying the type of gas turbine engine and number of propulsors. --- Findings - After an elaborate comparison of the aforementioned concepts, the all turbo-hydraulic propulsion system is found to be superior to the all turbo-electric propulsion system. A new propulsion system concept was developed by combining the thrust of a turbofan engine and utilizing the power produced by the turbo-hydraulic propulsion system that is delivered via propellers. The new partial turbo-hydraulic propulsion concept in which 20% of the total cruise power is coming from the (hydraulic driven) propellers is even more efficient than an all turbo-hydraulic concept in terms of DOC, environmental impact and fuel burn. --- Research Limitations - The aircraft were modelled with a spreadsheet based on handbook methods and relevant statistics. The investigation was done only for one type of reference aircraft and one route. A detailed analysis with a greater number of reference aircraft and types of routes could lead to other results. --- Practical Implications - With the provided spreadsheet, the DOC and environmental impact can be approximated for any commercial reference aircraft combined with the aforementioned propulsion system concepts. --- Social Implications - Based on the results of this thesis, the public will be able to discuss the demerits of otherwise highly lauded electric propulsion concepts. --- Value - To evaluate the viability of the hydraulic propulsion systems for passenger aircraft using simple mass models and aircraft design concept.

Purpose - This master thesis evaluates the hybrid-electric aircraft project E-Fan X with respect to its economical and environmental performance in comparison to its reference aircraft, the BAe 146-100. The E-Fan X is replacing one of the four jet engines of the reference aircraft by an electric motor and a fan. A turboshaft engine in the cargo compartment drives a generator to power the electric motor. --- Methodology - The evaluation of this project is based on standard aircraft design equations. Economics are based on Direct Operating Costs (DOC), which are calculated with the method of the Association of European Airlines (AEA) from 1989, inflated to 2019 values. Environmental impact is assessed based on local air quality (NOx, Ozone and Particulate Matter), climate impact (CO2, NOx, Aircraft-Induced Cloudiness known as AIC) and noise pollution estimated with fundamental acoustic equations. --- Findings - The battery on board the E-Fan X it is not necessary. In order to improve the proposed design, the battery was eliminated. Nevertheless, due to additional parts required in the new configuration, the aircraft is 902 kg heavier. The turboshaft engine saves only 59 kg of fuel. The additional mass has to be compensated by a payload reduced by 9 passengers. The DOC per seat-mile are up by more than 10% and equivalent CO2 per seat-mile are more than 16% up in the new aircraft. --- Research limitations - Results are limited in accuracy by the underlying standard aircraft design calculations. The results are also limited in accuracy by the lack of knowledge of some data of the project. --- Practical implications - The report contributes arguments to the discussion about electric flight. --- Social implications - Results show that unconditional praise given to the environmental characteristics of this industry project are not justified.

Tato práce se zabývá problematikou zavedení a provozu nadzvukových business jetů. V dnešní době se v civilní letecké přepravě, po ukončení provozu Concordu, žádná nadzvuková letadla nevyskytují. V dnešní době existuje mnoho projektů a organizací, které se zabývají znovuzavedením nadzvukových letounů do civilního letectví a soustředí se převážně na business jety. Hlavní otázkou je, zda je vůbec vhodné, či rozumné se k tomu typu dopravy znovu vracet. Existuje hodně problémů, které toto komplikují. Tyto letouny způsobují příliš velký hluk, mají obrovskou spotřebu paliva a musí řešit nadměrné emise, létají ve vysokých výškách ve kterých může docházet k problémům s přetlakováním kabiny, navigací, radioaktivním zářením apod. Navíc zákaz supersonických letů nad pevninou letové cesty omezuje a prodlužuje. Současně vznikající projekty navíc nedosahují tak velkého doletu jako klasické moderní bussjety, což způsobuje, že se nadzvukové business jety se na delších tratích stávají neefektivní. I přes tyto problémy, je víceméně jisté, že k zavedení nadzvukových business jetů dojde během následujících 10 - 15 let, i kdyby to měla být jen otázka jisté prestiže velmi bohatých lidí.