Examinando por Autor "Sor, Suthyvann"

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A comparative analysis of helicopter recovery maneuvers on a SFS by means of PIV and balance measurements
(Elsevier, 2023-05-23) Matías García, J. C.; Bardera, Rafael; Franchini, Sebastián; Barroso, Estela; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
The flow field around a frigate is complex due to flow detachments, high velocity gradients, and flow unsteadiness. These flow patterns can endanger helicopter operations around frigates and increase pilot workload above the flight deck. This paper contains a comparative analysis of three different recovery maneuvers: an approach from the stern in the centerline plane (S); a diagonal maneuver (D); and an L-shaped maneuver. The comparison is made using wind tunnel tests with a scaled frigate and a motorized helicopter. For the three maneuvers, velocity contours around the helicopter with Particle Image Velocimetry are obtained. An internal balance is also used to obtain forces and moments on the helicopter during the flight path of the maneuvers. Those measurements show that the wake of the ship mostly affects longitudinal and thrust forces. In addition, pitch torque is highly reduced when the helicopter is behind the frigate superstructure, and the roll moment is also important when the wind angle increases. In the end, an estimation of pilot workload is presented to conclude that L-shaped maneuver is the best for 0° and small WOD angles and D or S recoveries for moderately high negative WOD angles.
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Breakup criterion for droplets exposed to the unsteady flow generated by an incoming aerodynamic surface
(Elsevier, 2020-03-15) López Gavilan, Pablo; Velázquez, Ángel; García Magariño, A.; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)
An experimental and theoretical study is presented on the problem of droplet breakup exposed to a continuously accelerating flow generated by an incoming aerodynamics surface. Droplet breakup experiments were carried out in a rotating arm facility. Droplet diameters were of the order of 1 mm. The maximum velocity of the airfoils located at the end of the rotating arm was 90 m/s. Droplet deformation was computed using a phenomenological model developed previously by the authors. The dynamics of this deformation was coupled to an instability model based on the growth of Rayleigh-Taylor waves at the droplet surface. It was found that, within the experimental uncertainty, breakup occurs when the instability wavelength approaches the droplet hydraulic diameter assuming that it flattens and deforms as an oblate spheroid. This fact allowed for the generation of a theoretical closed-form droplet deformation and breakup model that predicts the onset of breakup with discrepancies of about ±10 % when compared to the experimental results. Finally, as an application case, this closed-form model is used to simulate an actual situation in which the objective is to investigate whether a series of droplets that are approached by an airfoil either impact on its surface, or break prior to collision, or break without colliding, or pass through undamaged.
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Characterization of an electrostatic filter prototype for bioaerosol flowmetering for INTA Investigation Aerial Platforms
(Elsevier, 2019-08-20) Bardera, Rafael; García Magariño, A.; González, Elena; Aguilera, Á.; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
The characterization of the airborne microorganisms at different altitudes of the atmosphere is usually conducted by means of aerial platforms. It is very interesting to know the biological processes in the atmosphere. However, there are problems associated to the fact that sampling systems are embarked on an aircraft and the low presence of microorganisms at high altitude. A prototype of a new electrostatic filter for bioaersol flowmetering dedicated to biology investigations has been developed. This prototype was designed to be installed on board in aerial platforms of INTA. The experimental characterization of the aerodynamic flow was performed in order to investigate the behaviour of the filter when different air intake widths and different mechanical deflectors are employed. A combination of these impactor with the filters based on industrial electrostatic precipitator technology have been studied. Non-intrusive Particle Image Velocimetry technique has been used to measure the flow field inside the filter when it was running under controlled conditions in laboratory. This study is a first investigation on the flow field of filter for bioaerosol flowmetering to be embarked on an aircraft. The results show the influence of each parameter in the flow field that could be used for further investigations and designs.
Acceso Abierto
Development and characterization of a low-cost wind tunnel balance for aerodynamic drag measurements
(IOP Science Publishing, 2019-06-17) Bardera, Rafael; García Magariño, A.; Matías García, J. C.; Donoso, Eduardo; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
Drag force measurement is one of the most important data that can be obtained in wind tunnel tests. Drag force is directly related to the energy that a vehicle needs to move, and, therefore, to the fuel costs associated with it. For vehicles, drag forces are usually measured in wind tunnels. The typical instruments for drag measurement are the force balances, which are usually complex and expensive instruments. The aim of this investigation is to study the development of a low-cost in-house balance for drag measurements in a wind tunnel. Based on a commercial available load cell XFTC300 Series in combination with simple elements designed and manufactured at INTA, a balance capable of measuring the drag force to models in a considerably wide adjustable range has been developed and characterized. The balance has been calibrated and used in a wind tunnel. Tests were carried out on a truck model, a simplified frigate shape and an Ahmed Body to obtain the resistance coefficient and evaluate the operation of the balance.
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Droplet breakup criterion in airfoils leading edge vicinity
(Aerospace Research Central, 2018-05-07) García Magariño, A.; Velázquez, Ángel; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)
A new breakup criterion is proposed in this paper for droplets subject to the flowfield generated by an incoming airfoil (that is, the criterion should be applied only to this type of aerodynamics flow). This criterion is based on the study of the characteristic times involved in the problem. These are the characteristic external flowfield variation time and the characteristic droplet deformation time. The criterion takes the shape of an empirical correlation that relates the Weber number at the onset of the breakup to the external flowfield and droplet characteristics. Experimental data on the droplet deformation and breakup tests conducted in a rotating arm facility are used to generate the data used to develop the correlation. Droplets, with diameters in the range of 0.3–3.6 mm, are allowed to fall in the path of an incoming airfoil attached to the end of a rotating arm. Airfoil velocities vary between 50 and 90 m∕s. The airfoil leading-edge radius varies from 0.030 to 0.103 m. Experiments are recorded with a high-speed camera using the shadowgraph illumination technique. The empirical breakup correlation applies to droplets that break in the bag and stamen mode. Some additional limited data on droplets that break in the bag and the shear mode are analyzed to see how they fit into the correlation.
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Droplet ratio deformation model in combination with droplet breakup onset modeling
(Aerospace Research Central, 2020-08-25) García Magariño, A.; Velázquez, Ángel; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)
Droplet deformation and breakup in the continuously accelerated flowfield generated by an incoming airfoil have been studied. The upper limit of droplet deformation and the minimum distance to the airfoil model at which the breakup onset takes place have been modeled. Three analytical equations have been developed based on the combination of two models: a droplet deformation and trajectory model for droplets in a continuously accelerated flowfield, and a breakup model for droplets in the vicinity of a leading edge of an airfoil model. The verification was made using experimental data obtained for water droplets whose diameters were in the range from 400 to 1800 μm impinging on airfoils of three different chord sizes moving at velocities from 50 to 90 m/s90 m/s. The rotating arm facility at National Institute of Aerospace Technology was used for this purpose. The analytical equations of the model were in good agreement with the experimental data. The upper limit of droplet deformation was verified by 95.40% of the tested experimental cases, and the minimum distance to the airfoil was verified in 99.65% of the cases.
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Experimental and numerical characterization of the Flow around the Mars 2020 Rover
(Aerospace Research Central, 2018-04-30) Bardera, Rafael; García Magariño, A.; Gómez Elvira, J.; Marín Jiménez, M.; Navarro, Sara; Torres Redondo, J.; Carretero, Sara; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
The investigation of the environmental factors in Mars atmosphere is one of the issues of the NASA’s Mars Exploration Program about the potential for life on Mars. The future Mars 2020 rover will transport the Mars Environmental Dynamics Analyzer dedicated to obtain meteorological data, as well as other objectives, about wind speed and direction. High-quality wind data are required to build mathematical models of the Mars climate; therefore, powerful techniques are necessary to eliminate flow perturbations produced by the rover presence. The aim of this Paper is the characterization of the flow around the Mars 2020 rover, providing a deep insight into the environmental interaction of the Mars wind with the rover. A comparative study between numerical simulations versus wind-tunnel experimental results is conducted trying to investigate the influence of the rover on the flow measured by the Mars Environmental Dynamics Analyzer wind sensors. This study is addressed to perform an assessment of the reliability of numerical methods in the prediction of this kind of flow in Martian conditions, evaluating its capability to be used in the future to correct wind data coming from the Mars 2020 rover mission. The advancements in the numerical methods as compared with experimental results implies an advancement on the calibration methods in the space wind sensor instrumentation carried in the Mars 2020 rover.
Acceso Abierto
From pomegranate byproducts waste to worth: A review of extraction techniques and potential applications for their revalorization
(EDP Sciences, 2024-04-17) García Rodríguez, J. A.; Sor, Suthyvann; García Magariño, A.
The food industry is quite interested in the use of (techno)-functional bioactive compounds from byproducts to develop ‘clean label’ foods in a circular economy. The aim of this review is to evaluate the state of the knowledge and scientific evidence on the use of green extraction technologies (ultrasound-, microwave-, and enzymatic-assisted) of bioactive compounds from pomegranate peel byproducts, and their potential application via the supplementation/fortification of vegetal matrixes to improve their quality, functional properties, and safety. Most studies are mainly focused on ultrasound extraction, which has been widely developed compared to microwave or enzymatic extractions, which should be studied in depth, including their combinations. After extraction, pomegranate peel byproducts (in the form of powders, liquid extracts, and/or encapsulated, among others) have been incorporated into several food matrixes, as a good tool to preserve ‘clean label’ foods without altering their composition and improving their functional properties. Future studies must clearly evaluate the energy efficiency/consumption, the cost, and the environmental impact leading to the sustainable extraction of the key bio-compounds. Moreover, predictive models are needed to optimize the phytochemical extraction and to help in decision-making along the supply chain.
Acceso Abierto
Impacts of Saharan Dust Intrusions on Bacterial Communities of the Low Troposphere
(Springer Nature Research Journals, 2020-04-22) González Toril, Elena; Osuna, Toril; Viúdez Moreiras, Daniel; Navarro Cid, Ivan; Díaz del Toro, Silvia; Bardera, Rafael; Puente Sánchez, Fernando; De Diego Castilla, Graciela; Aguilera, Á.; Sor, Suthyvann; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We have analyzed the bacterial community of a large Saharan dust event in the Iberian Peninsula and, for the first time, we offer new insights regarding the bacterial distribution at different altitudes of the lower troposphere and the replacement of the microbial airborne structure as the dust event receeds. Samples from different open-air altitudes (surface, 100 m and 3 km), were obtained onboard the National Institute for Aerospace Technology (INTA) C-212 aircrafts. Samples were collected during dust and dust-free air masses as well two weeks after the dust event. Samples related in height or time scale seems to show more similar community composition patterns compared with unrelated samples. The most abundant bacterial species during the dust event, grouped in three different phyla: (a) Proteobacteria: Rhizobiales, Sphingomonadales, Rhodobacterales, (b) Actinobacteria: Geodermatophilaceae; (c) Firmicutes: Bacillaceae. Most of these taxa are well known for being extremely stress-resistant. After the dust intrusion, Rhizobium was the most abundant genus, (40–90% total sequences). Samples taken during the flights carried out 15 days after the dust event were much more similar to the dust event samples compared with the remaining samples. In this case, Brevundimonas, and Methylobacterium as well as Cupriavidus and Mesorizobium were the most abundant genera.
Acceso Abierto
Impacts of Saharan Dust Intrusions on Bacterial Communities of the Low Troposphere
(Springer Nature Research Journals, 2020-04-22) González Toril, Elena; Viúdez Moreiras, Daniel; Navarro Cid, Ivan; Díaz del Toro, Silvia; Bardera, Rafael; Sánchez, F. P.; De Diego Castilla, Graciela; Aguilera, Á.; Osuna Esteban, Susana; Sor, Suthyvann; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Sor, S. https://orcid.org/0000-0002-6972-8601
We have analyzed the bacterial community of a large Saharan dust event in the Iberian Peninsula and, for the first time, we offer new insights regarding the bacterial distribution at different altitudes of the lower troposphere and the replacement of the microbial airborne structure as the dust event receeds. Samples from different open-air altitudes (surface, 100 m and 3 km), were obtained onboard the National Institute for Aerospace Technology (INTA) C-212 aircrafts. Samples were collected during dust and dust-free air masses as well two weeks after the dust event. Samples related in height or time scale seems to show more similar community composition patterns compared with unrelated samples. The most abundant bacterial species during the dust event, grouped in three different phyla: (a) Proteobacteria: Rhizobiales, Sphingomonadales, Rhodobacterales, (b) Actinobacteria: Geodermatophilaceae; (c) Firmicutes: Bacillaceae. Most of these taxa are well known for being extremely stress-resistant. After the dust intrusion, Rhizobium was the most abundant genus, (40–90% total sequences). Samples taken during the flights carried out 15 days after the dust event were much more similar to the dust event samples compared with the remaining samples. In this case, Brevundimonas, and Methylobacterium as well as Cupriavidus and Mesorizobium were the most abundant genera.
Acceso Abierto
Impacts of Saharan Dust Intrusions on Bacterial Communities of the Low Troposphere
(Spring Nature Research Journals, 2020-04-22) González Toril, Elena; Viúdez Moreiras, Daniel; Navarro Cid, Ivan; Del Toro, Silvia Díaz; Bardera, Rafael; Puente Sánchez, Fernando; De Diego Castilla, Graciela; Aguilera, Á.; Osuna Esteban, Susana; Sor, Suthyvann; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); 0000-0002-5750-0765; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We have analyzed the bacterial community of a large Saharan dust event in the Iberian Peninsula and, for the first time, we offer new insights regarding the bacterial distribution at different altitudes of the lower troposphere and the replacement of the microbial airborne structure as the dust event receeds. Samples from different open-air altitudes (surface, 100 m and 3 km), were obtained onboard the National Institute for Aerospace Technology (INTA) C-212 aircrafts. Samples were collected during dust and dust-free air masses as well two weeks after the dust event. Samples related in height or time scale seems to show more similar community composition patterns compared with unrelated samples. The most abundant bacterial species during the dust event, grouped in three different phyla: (a) Proteobacteria: Rhizobiales, Sphingomonadales, Rhodobacterales, (b) Actinobacteria: Geodermatophilaceae; (c) Firmicutes: Bacillaceae. Most of these taxa are well known for being extremely stress-resistant. After the dust intrusion, Rhizobium was the most abundant genus, (40–90% total sequences). Samples taken during the flights carried out 15 days after the dust event were much more similar to the dust event samples compared with the remaining samples. In this case, Brevundimonas, and Methylobacterium as well as Cupriavidus and Mesorizobium were the most abundant genera.
Acceso Abierto
Interferometric laser imaging for droplet sizing method for long range measurements
(Elsevier, 2021-01-15) García Magariño, A.; Sor, Suthyvann; Muñoz Campillejo, Javier; Bardera, Rafael; García Magariño, A.; Sor, Suthyvann; Muñoz-Campillejo, Javier; Instituto Nacional de Técnica Aeroespacial (INTA)
A recent appendix in the aircraft regulations comprises testing supercooled large droplets impinging on its surfaces. For those tests, the size and distributions of droplets need to be characterized in icing wind tunnels. In this paper, the applicability of implementation of the “Interferometric Laser Imaging for Droplet Sizing” technique inside a wind tunnel with a 3 m × 2 m open elliptical test section has been discussed. Experiments have been conducted in the laboratory for the discussion at object distance of 1.6 m and 2.29 m and droplets diameters between 360 µm and 850 µm. All the streams were previously characterized by means of the shadowgraph imaging technique. A novel approach of the Interferometric Laser Imaging for Droplet Sizing technique where droplets are not fully defocused to avoid excessive overlapping is presented. Two new image processing approaches provide in general good results as compared to previous methods.
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Mars 2020 Rover Influence on Wind Measurements at Low Reynolds Number
(Aerospace Research Central, 2019-02-11) Bardera, Rafael; García Magariño, A.; Urdiales, María del Mar; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
The Mars 2020 rover is the new vehicle dedicated to the Martian surface investigation. This vehicle will transport Mars Environmental Dynamic Analyzer, the new meteorological station, including two wind sensors installed in the camera mast. An experimental characterization was conducted to investigate the influence of the Mars 2020 rover in the Mars Environmental Dynamic Analyzer wind measurements at low Reynolds numbers. Wind tunnel experiments were conducted using a 1:45th scaled model in a wind tunnel specially designed for these experiments. The velocity was measured using laser Doppler anemometry. A method is proposed in this investigation to calculate a correction factor for the data measurements of wind sensors embarked on rovers dedicated to planetary exploration missions. In particular, the method was applied to wind measurements taken by Mars Environmental Dynamic Analyzer in the Mars 2020 rover using the laser Doppler anemometry measurements, and corrections up to 40% in the velocity magnitude and 23 deg in the deflection angle were found.
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Mars 2020 Wind Velocity Measurement Interferences at High Reynolds Numbers
(Aerospace Research Central, 2019-12-29) García Magariño, A.; Bardera, Rafael; Muñoz, Javier; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
The Mars Environmental Dynamics Analyzer will be dedicated to getting meteorological data from Mars during NASA’s Mars 2020 rover mission. High-quality Mars atmosphere measurements are required in order to build mathematical models of the climate on a planetary scale. The Mars 2020 rover will be equipped with two wind sensors installed on two separated booms working in active redundancy but producing a mutual aerodynamic interference on one another’s wind measurements. This paper presents a systematic study on the interferences produced by the sensors and the rover body itself when measuring wind velocities in order to get insight to assess the uncertainties produced by this effect.
Acceso Abierto
Micro/Bubble drag reduction focused on new applications
(Multidisciplinary Digital Publishing Institute (MDPI), 2023-06-28) García Magariño, A.; López Gavilan, Pablo; Terroba, F.; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA)
Bubble drag reduction has been shown to be a promising technique for reducing the drag in ships, thus reducing the emission of pollutants and allowing the compliance with the new requirements imposed recently in this respect. Different searches have been conducted in the publications related to this technique, and an increase in interest has been shown, especially in the last decade. In this context, a review of the experimental work related to bubble drag reduction published in the last decade is presented in the present article. The works were classified according to the facility used (towing tank, cavitation tunnel, water channel, Taylor–Couette…), and the main finding are presented. It was found that two new trends in research have arisen, while there are still contradictions in the fundamental basis, which needs further study.
Acceso Abierto
New droplet aero-breakup mechanism associated to unsteady flow loading
(Elsevier, 2021-02-20) García Magariño, A.; Velázquez, Ángel; Sor, Suthyvann; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)
Experimental testing on the unsteady aero-breakup of ethyl alcohol droplets was carried out at the rotating arm facility of INTA. The selection of the working fluid was driven by the need to explore wider ranges of the dimensionless parameters that govern the problem. A model airfoil was attached at the end of a 2.3 m long rotating arm driven by an electric motor. Droplets, whose diameter ranged from 500 mm to 1500 mm, were allow to fall in the path of the airfoil that attained velocities in the range between 30 m/s and 60 m/s. Droplets trajectories and breakup modes were recorded, and a new breakup mode was identified. Its sequence is as follows: 1) the droplet deforms as an oblate spheroid, 2) a bulge appears and grows on its flow facing surface, 3) the droplet thickens in the stream-wise direction; 4) the thickening in the rear part of the droplet develops in the shape of a cone, 5) the cone grows thinner until a finger like shape is formed. Additionally, based on a theoretical model developed by the authors, a comparison has been made between the deformation and breakup onset phases of ethyl-alcohol and water droplets up to the instant of breakup.