Modelado de la combustión de propulsante para problemas de balística interior

Se presenta un modelo para el estudio de problemas de balística interior que implican el análisis de una mezcla bifásica de sólidos (pólvora/propulsante) y gases (productos de la combustión). Dicho modelo está basado en una aproximación unidimensional por Volúmenes Finitos de un conjunto de ecuaciones adaptadas del modelo no conservativo de Gough. El cálculo de los flujos numéricos en la interfase se hace mediante solvers aproximados de Riemann, en concreto los esquemas numéricos aplicados son el esquema de Rusanov y el AUSM+. En este trabajo se introducen las ecuaciones correspondientes al modelo y las relaciones de cierre necesarias para caracterizar los fenómenos físicos que ocurren durante la combustión y como consecuencia de la interacción entre las fases: velocidad de combustión, fricción, tensión interfacial y transferencia de calor interfacial. Además, se realiza la validación del código desarrollado. Para ello se presenta un test experimental, las condiciones del mismo y los resultados experimentales se comparan con los obtenidos con el modelo implementado. También se contrastan los resultados obtenidos con los de otros programas que utilizan aproximaciones 0D (Balint) o aproximaciones unidimensionales (FNGun). Para finalizar, se expondrán algunas conclusiones de los resultados obtenidos con este modelo.Este trabajo ha sido financiado mediante un proyecto de investigación del “Ministerio de Industria, Energía y Turismo” a través de la convocatoria INNPACTO denominado “Smart Propellants” (IPT-2011-0712-020000) que involucra a EXPAL Systems S.A. y a la Universidad Politécnica de Cartagena (UPCT). Parte de esta ayuda ha sido financiada con fondos FEDER

High resolution spectroscopy of the BCD galaxy Haro 15: II. Chemodynamics

We present a detailed study of the physical properties of the nebular material in four star-forming knots of the blue compact dwarf galaxy Haro 15. Using long-slit and echelle spectroscopy obtained at Las Campanas Observatory, we study the physical conditions (electron density and temperatures), ionic and total chemical abundances of several atoms, reddening and ionization structure, for the global flux and for the different kinematical components. The latter was derived by comparing the oxygen and sulphur ionic ratios to their corresponding observed emission line ratios (the $\eta$ and $\eta$' plots) in different regions of the galaxy. Applying the direct method or empirical relationships for abundance determination, we perform a comparative analysis between these regions. The similarities found in the ionization structure of the different kinematical components implies that the effective temperatures of the ionizing radiation fields are very similar in spite of some small differences in the ionization state of the different elements. Therefore the different gaseous kinematical components identified in each star forming knot are probably ionized by the same star cluster. However, the difference in the ionizing structure of the two knots with knot A showing a lower effective temperature than knot B, suggests a different evolutionary stage for them consistent with the presence of an older and more evolved stellar population in the first.Comment: 21 pages, 6 figures, 8 tables, accepted by MNRA

European Journalism Observatory- a platform for training and professional networks in the Faculty of Information Sciences

The launching of a Spanish platform within the Observatory will serve as a training laboratory for undergraduate and graduate students of the Faculty of Information Sciences at the same time as for establishing a professional media network in and outside Spain. The European Journalism Observatory (EJO) is a network of 14 non-profit media research institutes in 11 countries where Spain continue to be the missing element. All researchers in the EJO network actively strive to transfer their knowledge to the media industry as well as interested publics outside the scientific community, as a platform to enable online availability of at least a portion of many publications in several languages

Abundance determination of multiple star-forming regions in the HII galaxy SDSS J165712.75+321141.4

We analyze high signal-to-noise spectrophotometric observations acquired simultaneously with TWIN, a double-arm spectrograph, from 3400 to 10400 \AA of three star-forming regions in the HII galaxy SDSS J165712.75+321141.4. We have measured four line temperatures: Te([OIII]), Te([SIII]), Te([OII]), and Te([SII]), with high precision, rms errors of order 2%, 5%, 6% and 6%, respectively, for the brightest region, and slightly worse for the other two. The temperature measurements allowed the direct derivation of ionic abundances of oxygen, sulphur, nitrogen, neon and argon. We have computed CLOUDY tailor-made models which reproduce the O2+ measured thermal and ionic structures within the errors in the three knots, with deviations of only 0.1 dex in the case of O+ and S2+ ionic abundances. In the case of the electron temperature and the ionic abundances of S+/H+, we find major discrepancies which could be consequence of the presence of colder diffuse gas. The star formation history derived using STARLIGHT shows a similar age distribution of the ionizing population among the three star-forming regions. This fact suggests a similar evolutionary history which is probably related to a process of interaction with a companion galaxy that triggered the star formation in the different regions almost at the same time. The hardness of the radiation field mapped through the use of the softness parameter $\eta$ is the same within the observational errors for all three regions, implying that the equivalent effective temperature of the radiation fields are very similar for all the studied regions of the galaxy, in spite of some small differences in the ionization state of different elements.Comment: 18 pages, 10 figures, accepted by MNRA

Diseño y control de una instalación experimental de evaporación en tubo multipuerto

Consulta en la Biblioteca ETSI Industriales (8270)[ES] El objetivo que se persigue con este proyecto, es diseñar y poner en marcha una instalación experimental para estudiar los procesos de evaporación en tubos del tipo multipuerto. Dicha instalación permitirá ensayar diferentes fluidos refrigerantes en una serie de tubos con microcanales de diferente geometría y características, y proporcionará los datos para su posterior análisis. De esta manera se persigue diseñar, montar, construir y calibrar la mencionada instalación para a posteriori trabajar con ella y recoger los datos necesarios de los ensayos pertinentes y así poder desarrollar modelos matemáticos que permitan determinar el coeficiente de transmisión de calor y la caída de presión en estos tubos y que ayude en el diseño de estos componentes y permita avanzar en el modelado de los equipos de refrigeración en su conjunto. Asimismo ser capaces de predecir las prestaciones con una precisión tal que puedan utilizarse para hacer estudios de diseño y optimización de equipos e instalaciones. Otro de los principales objetivos es el control de la instalación, para ello se hará el modelado de la instalación y posteriormente se usará una herramienta de MatLab, Simulink, para hacer la simulación de nuestro modelo. A partir de aquí, se estudiarán diferentes controladores, ¿bang-bang¿ con sus diferentes topologías, haciendo especial hincapié en el socorrido PID, donde se hará un estudio con las posibles concreciones (P, PI, PD, PID)Monreal González, G. (2010). Diseño y control de una instalación experimental de evaporación en tubo multipuerto. http://hdl.handle.net/10251/33056.Archivo delegad

HIV-infection impact on clinical-biological features and outcome of diffuse large B-cell lymphoma treated with R-CHOP in the combination antiretroviral therapy era

OBJECTIVE:: Since the introduction of combination antiretroviral therapy (cART) patients with HIV-related diffuse large B-cell lymphoma (DLBCL) show better control of immunosuppression, which may have an impact on the characteristics and prognosis of the disease. We aimed to compare the clinical presentation and prognosis of patients with HIV-related and HIV-unrelated DLBCL treated with R-CHOP in the cART era. METHODS AND DESIGN:: Eighty-one HIV-infected patients included in a Spanish multicentre trial were compared with 84 HIV-uninfected patients diagnosed in a Spanish institution in the same period all treated with R-CHOP. RESULTS: HIV-infected patients had a worse performance status, more frequent B-symptoms, and higher Ann-Arbor stages than HIV-uninfected patients, with similar frequency of extranodal involvement. The complete response (CR) rate of patients with high tumor burden was not different in HIV-infected and HIV-uninfected patients. Patients with HIV-related DLBCL showed a worse overall survival (OS) (5-year OS: 56 vs. 74%) but a similar disease-free survival (DFS) (5-year DFS: 84 vs. 73%). In the subgroup of patients with high tumor, the results regarding survival were similar to the whole series. Previous AIDS-defining illness was the strongest negative prognostic factor for OS in HIV-infected patients. CONCLUSION: In the cART era, HIV-related DLBCL still presents more aggressive features than HIV-unrelated DLBCL, and has a worse OS despite having a similar DFS. Prevention of HIV-related complications is essential to achieve outcomes comparable with HIV-uninfected patients with DLBCL