Combustion of High-Pressure Hydrogen Diluted Mixtures in ESTHER Shock Tube Ricardo Grosso Ferreira, Bernardo Brotas Carvalho, Rafael Rodrigues, Luís Lemos Alves, Bruno Gonçalves, et al. Journal of Thermophysics and Heat Transfer, 2024 European Shock Tube for High-Enthalpy Research (ESTHER) is a new state-of-the-art combustion-driven shock tube developed for supporting future ESA planetary exploration missions. Its high-pressure combustion driver sports a unique innovative design where a mixture of [Formula: see text] or [Formula: see text] gases, filled to pressures up to 100 bar, is ignited by a high-power Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The qualification of this facility driver has allowed for the detailed study of laser-ignited combustion processes at high initial pressures (in the 5–100 bar range), over a series of 100 shots carried out for different configurations and gas mixtures. The influence of the oxygen-to-hydrogen ratio, filling pressure, inert gas dilution, and ignition mode have been studied and are presented in this work. The effects of nitrogen vs helium dilution are also discussed. Filling pressure and helium/nitrogen dilutions have the strongest influence in peak pressure, acoustic oscillation, and combustion velocity. The first two increase, whereas the latter strongly decreases with the filling pressure. Nitrogen diluted shots have drastically lower compression ratios and flame velocity when compared to the helium ones. Acoustic perturbations/instabilities are also found to be stronger. This test campaign allowed the definition of a large range of stable and reproducible firing conditions in deflagration mode, yielding post-combustion pressures up to 660 bar.
VUV to IR Emission Spectroscopy and Interferometry Diagnostics for the European Shock Tube for High-Enthalpy Research Ricardo Grosso Ferreira, Bernardo Brotas Carvalho, Luís Lemos Alves, Bruno Gonçalves, Victor Fernandez Villace, et al. Sensors, 2023 The European Shock Tube for High-Enthalpy Research is a new state-of-the-art facility, tailored for the reproduction of spacecraft planetary entries in support of future European exploration missions, developed by an international consortium led by Instituto de Plasmas e Fusão Nuclear and funded by the European Space Agency. Deployed state-of-the-art diagnostics include vacuum-ultraviolet to ultraviolet, visible, and mid-infrared optical spectroscopy setups, and a microwave interferometry setup. This work examines the specifications and requirements for high-speed flow measurements, and discusses the design choices for the main diagnostics. The spectroscopy setup covers a spectral window between 120 and 5000 nm, and the microwave interferometer can measure electron densities up to 1.5 × 1020 electrons/m3. The main design drivers and technological choices derived from the requirements are discussed in detail herein.
Spectral observations at the Canary Island Long-Baseline Observatory (CILBO): Calibration and datasets Joe Zender, Detlef Koschny, Regina Rudawska, Salvatore Vicinanza, Stefan Loehle, et al. Geoscientific Instrumentation Methods and Data Systems, 2023 The Canary Island Long-Baseline Observatory (CILBO) is a double-station meteor camera setup located on the Canary Islands operated by ESA's Meteor Research Group since 2010. Observations of meteors are obtained in the visual wavelength band by intensified video cameras from both stations, supplemented by an intensified video camera mounted with a spectral grating at one of the locations. The cameras observe during cloudless and precipitation-free nights, and data are transferred to a main computer located at ESA/ESTEC once a day. The image frames that contain spectral information are calibrated, corrected, and finally processed into line intensity profiles. An ablation simulation, based on Bayesian statistics using a Markov chain Monte Carlo method, allows determining a parameter space, including the ablation temperatures, chemical elements, and their corresponding line intensities, to fit against the line intensity profiles of the observed meteor spectra. The algorithm is presented in this paper and one example is discussed. Several hundred spectra have been processed and made available through the Guest Archive Facility of the Planetary Science Archive of ESA. The data format and metadata are explained.
Demise observation capsule: Progress update 2018 Proceedings of the International Astronautical Congress Iac, 2018
Influence of ablation on vacuum-ultraviolet radiation in a plasma wind tunnel flow Tobias Hermann, Stefan Löhle, Stefanos Fasoulas, Pénélope Leyland, Lionel Marraffa, et al. Journal of Thermophysics and Heat Transfer, 2017 Plasma wind tunnel experiments have been performed simulating a Hayabusa reentry trajectory point at 78.8 km altitude with a velocity of 11.7 km/s corresponding to a local mass–specific enthalpy o...
Dynamic characteristics of MarcoPolo-R Entry Capsule in low subsonic flow Arianit Preci, Ali Gülhan, Etienne Clopeau, Philippe Tran, Luca Ferracina, et al. Ceas Space Journal, 2016 The selection of the most suitable configuration between several candidate aeroshapes for the MarcoPolo-R ERC is performed by means of subsonic dynamic stability tests. These tests were conducted in the vertical free jet facility VMK at the German Aerospace Center (DLR) in Cologne, employing the free flight technique. Several different model configurations with respect to the shape, position of the centre of gravity, shoulder radius, and mass were tested. The motion of the models during free flight was recorded using an optical motion tracking system. The measurement of the position and the attitude of the models, in combination with flow parameters and an exact flow profile characterization, allows for a shape discrimination based on aerodynamic stability characteristics of the models.
Supersonic tests of the double gap disk-gap band parachute and fluid structure interaction simulation Aerodynamic Decelerator Systems Technology Conferences, 2015
Supersonic parachute aerodynamic testing J. Stephen Lingard, John C. Underwood, Matthew G. Darley, Lionel Marraffa, Luca Ferracina AIAA Aerodynamic Decelerator Systems Ads Conference 2013, 2013
Sounding rocket flight test of propellant management technologies 61st International Astronautical Congress 2010 Iac 2010, 2010
Dust particle erosion during mars entry 40th International Conference on Environmental Systems ICES 2010, 2010
Radiation of high temperature gases: Rebuilding test case TC2 European Space Agency Special Publication ESA SP, 2009
Rebuilding the test case tc2-t2: Definition of shock tunnel test-cases for gas radiation prediction in titan-like atmosphere - Iusti experiments - European Space Agency Special Publication ESA SP, 2009
The tandem mission proposal a first estimation of the foreseeable radiative heat fluxes the montgolfiÈre probe will encounter during its entry in titan atmosphere European Space Agency Special Publication ESA SP, 2009
