Prestaciones y cualidades de vuelo del ISA 180 Seeker con propulsión eléctrica

[ES] El ISA 180 Seeker es un avión de doble brazo diseñado por el diseñador de aviones Ivan Shaw. Es un pequeño avión con capacidad para una persona. Con una longitud de 5,2 m y una envergadura de 5,8 m, este avión tiene una aerodinámica muy buena gracias a su condición de doble botavara y ala casi voladora. Estas características, además de un peso vacío de 260 kg, lo convierten en un avión ideal para estudiar la conversión a propulsión eléctrica. Por lo tanto, el proyecto consistirá en el diseño de un sistema de propulsión eléctrica adecuado para esta aeronave que sustituya al actual motor bóxer de 4 cilindros (Rotax 912 iS) y al resto del tren motopropulsor actual. Además, con el nuevo sistema de propulsión será necesario obtener un cierto nivel de rendimiento en términos de calidad de vuelo y especificaciones. Como punto de partida, Ivan Shaw compartió con nosotros el modelo X-Plane de su aeronave, y nos permitirá estudiar las actuales cualidades de vuelo y rendimiento para llevar a cabo el estudio deseado. En primer lugar, será necesario obtener datos técnicos de los datos actuales en términos de rendimiento aerodinámico, valores actuales de velocidad, pesos, ubicaciones, etc. Pero, la principal fuente de información serán los datos del modelo X Plane dado. Como hemos mencionado, el proyecto consistirá en estudiar una nueva configuración de propulsión eléctrica para esta aeronave en particular. Para ello, será necesario llevar a cabo una enorme investigación sobre las centrales eléctricas, utilizando como referencia algunos prototipos diseñados por las empresas (i.e. AIRBUS E-fan) o utilizando como guía para las baterías de la industria del automóvil, cuando se ha hecho una gran cantidad de mejoras en términos de almacenamiento de energía. (i.e. Tesla y Toyota). Será necesario determinar la batería óptima, el motor, los ESC de alta corriente, etc. En este proyecto también se evaluará la posibilidad de utilizar más de un motor, más de una batería y evaluar más de un tipo de configuración del grupo motopropulsor. También dando a la aeronave un sistema de propulsión redundante. Una vez que la distribución de la configuración de la propulsión quede clara como parte de la aeronave, se realizará un estudio de la dinámica de vuelo para probar las cualidades de vuelo de la aeronave que se va a certificar. Para ello, se realizará un modelo de simulación de aeronave (X-Plane). Para lograr el alcance general del proyecto será necesario establecer algunos objetivos que construirán el proyecto paso a paso. Los objetivos generales para lograr el alcance general son: Obtención de la documentación de la aeronave, Diseño Eléctrico tren de potencia, Estabilidad en mecánica vuelo y las cualidades de vuelo.[EN] The ISA 180 Seeker is a twin-boom aircraft designed by the aircraft designer Ivan Shaw. It is a small aircraft with capacity for one person. With a length of 5.2 m and a wingspan of 5.8 m, this aircraft has a very good aerodynamics thank to its condition of twin boom and almost flying wing. This Features, in addition to an Empty weigh of 260 kg, make it an ideal aircraft to study the conversion to electrical propulsion. Therefore, the project will consist on the design of a suitable electrical propulsion system for this aircraft replacing the current 4 cylinders boxer engine (Rotax 912 iS) and the rest of the current power train. Moreover, it will be necessary to obtain certain level of performance in terms of flying qualities and specifications with the new propulsion system. As a point of departure Ivan Shaw shared with us the X-Plane model of his aircraft, and it will allow us to study the current flying qualities and performance to carry out the desired study. First of all, it will be necessary to obtain technical data from the current data in terms of aerodynamic performance, current values of speed, weighs, locations, etc. But, the main source of information will be data from the X Plane model given. As we have mentioned the project will consist on study a new electrical propulsion configuration for this particular aircraft. For that, it will be necessary carry out a huge research on electrical power plants, using as a reference some prototypes designed by Companies (i.e. AIRBUS E-Fan) or using as a guide for batteries the automotive industry, when a large amount of improvements in term of energy storage has been done. (i.e. Tesla and Toyota). It will be necessary to determine the optimum battery, engine, high-current ESCs, etc. On this project it will be also assessed the possibility of using more than one engine, more than one battery and asses more than one type of power train configuration. Also giving to the aircraft a redundant propulsion system. Once the distribution of the propulsion configuration is clear as a part of the aircraft, a flight dynamics study will be done in order to test the flying qualities the viability of the aircraft to be certified. In order to do so, an aircraft simulation model (X-Plane) will be performed. In order to achieve the general scope of the project it will be necessary to establish some objectives that will be building the project step by step. The general aims to achieve the general scope are: Obtaining Aircraft documentation, Design Electrical power train, Asses Stability flight dynamics and flying qualities.Rupérez Vírseda, IJ. (2020). Performance and flying qualities of the ISA 180 Seeker with electrical propulsion. Universitat Politècnica de València. http://hdl.handle.net/10251/148342TFG

Metamagnetism in a coordination polymer built of trimeric cobalt units and melamine

A coordination polymer of linear trimeric cobalt units and melamine has been synthesized. The magnetic isotherms of violet coloured crystals as long as 400 μm show a field-induced transition in an external field of about 2 T at temperatures approximately below 2 K. It is addressed that by assuming the coexistent positive and negative exchange between the nearest-neighbour spins in the linear trimer, this metamagnetism can be interpreted as a transition from antiferromagnetic to ferromagnetic exchange within each trimeric spin cluster. Although weak inter-cluster or inter-chain exchange to yield a long-range magnetic order is another possible and often attributed origin of metamagnetism in low-dimensional spin systems, this study demonstrates the significance of the exchange flip within each cluster in clustered spin networks

Crystal Engineering with Copper and Melamine

Coordination complex and polymer are central in inorganic and material chemistry as a variety of both metal centers and coordination geometries lead to a diverse range of interesting properties. Here, size and structure control of gems-like quality monocrystals are demonstrated at room temperature. From the same set of precursors, but the copper-to-melamine molar ratio is adjusted to synthesize either a novel coordination complex of dinuclear copper and melamine (Cu2M1) or a barely-studied coordination polymer of zigzag copper-chlorine chains (Cu4M1). Crystals of the former are dark green and squared with the size up to 350 µm across. The latter is light green and octagonal as large as 5 mm across. The magnetic properties of both crystals reflect their low-dimensional arrangements of copper. The magnetic susceptibility of Cu2M1 is well modelled with a spin-1/2 dimer and that of Cu4M1 with a spin-1/2 one-dimensional Ising chain. Controlled synthesis of such quality magnetic crystals is a prerequisite for various magnetic and magneto-optical applications<br /

Cardiac troponin and COVID-19 severity: Results from BIOCOVID study.

Myocardial injury is a common finding in COVID-19 strongly associated with severity. We analysed the prevalence and prognostic utility of myocardial injury, characterized by elevated cardiac troponin, in a large population of COVID-19 patients, and further evaluated separately the role of troponin T and I. This is a multicentre, retrospective observational study enrolling patients with laboratory-confirmed COVID-19 who were hospitalized in 32 Spanish hospitals. Elevated troponin levels were defined as values above the sex-specific 99th percentile upper reference limit, as recommended by international guidelines. Thirty-day mortality was defined as endpoint. A total of 1280 COVID-19 patients were included in this study, of whom 187 (14.6%) died during the hospitalization. Using a nonspecific sex cut-off, elevated troponin levels were found in 344 patients (26.9%), increasing to 384 (30.0%) when a sex-specific cut-off was used. This prevalence was significantly higher (42.9% vs 21.9%; P  In this multicentre study, myocardial injury was a common finding in COVID-19 patients. Its prevalence increased when a sex-specific cut-off and cardiac troponin T were used. Elevated troponin was an independent predictor of 30-day mortality, irrespective of cardiac troponin assay and cut-offs to detect myocardial injury. Hence, the early measurement of cardiac troponin may be useful for risk stratification in COVID-19