Simultaneous high-speed spectroscopy and 2-color pyrometry analysis in an optical compression ignition engine fueled with OME X -diesel blends

[EN] E-fuels are a very attractive way for improving the well-to-wheel emissions of CO 2 in internal combustion engines. In the particular case of compression ignition engines, the Oxymethylene dimethyl ether (OME X ), an e-fuel with nearly soot-free combustion under mixing-controlled conditions, is a good candidate for the replacement of fossil fuels. However, the Lower Heating Value of OME X is nearly half of the diesel fuel, which means that much longer injection durations are required in the real engine. In addition, the very low viscosity and lubricity of OME X can damage the injection system if used pure, but it can be an interesting fuel when blended with conventional diesel. Thus, the main objective of this paper is to evaluate the potential of OME X -diesel blends to bypass these OME X limitations whilst keeping low soot formation trends. For this purpose, a single cylinder optical diesel engine at part load was employed. The soot production for the different fuel blends was analyzed by applying three different high-speed imaging techniques: natural luminosity, flame spectroscopy and 2-color pyrometry. Natural luminosity analysis showed that the flame light intensity scales with diesel fraction up to 30% of diesel in the blend. The spectroscopy analysis has revealed that soot formation of OME X fuel is almost null. When blended with diesel at 50%, although soot formation is still lower than for pure diesel, higher soot levels are obtained in the last stages of the cycle as a consequence of the longer injections required.This work was partially funded by Generalitat Valenciana through the Programa Santiago Grisola (GRISOLIAP/2018/142) program.Pastor, JV.; García Martínez, A.; Micó, C.; De Vargas Lewiski, F. (2021). Simultaneous high-speed spectroscopy and 2-color pyrometry analysis in an optical compression ignition engine fueled with OME X -diesel blends. Combustion and Flame. 230:1-13. https://doi.org/10.1016/j.combustflame.2021.111437S11323

Uso de aplicaciones de móviles para mejorar la adherencia al ejercicio en pacientes con enfermedad arterial periférica

[Resumen] Objetivos. La enfermedad arterial periférica es una enfermedad arterial oclusiva crónica de las extremidades inferiores. El ejercicio supervisado en un centro hospitalario es una intervención fundamental para su tratamiento, o en su defecto el ejercicio domiciliario es igual de eficaz siempre y cuando se lleve a cabo. El objetivo principal es demostrar la utilidad del uso de aplicaciones de móviles para mejorar la adherencia al ejercicio domiciliario. Como objetivos secundarios: confirmar la eficacia del uso del cilostazol y el abandono del hábito tabáquico en la mejoría de la distancia de claudicación. Metodología. Se ha realizado un estudio piloto de un futuro estudio experimental, ensayo clínico controlado, aleatorizado, en paralelo y no ciego, realizado por el servicio de Angiología y Cirugía Vascular del Hospital Virgen del Rocío con un periodo de duración de 10 meses. Se incluyeron a individuos que padecen la Enfermedad arterial periférica grado II de la clasificación de la Fontaine. Consideramos grupo control a los individuos que reciben las indicaciones habituales para realizar ejercicio domiciliario y grupo experimental a los individuos que además de las indicaciones habituales, se les explica el uso de las aplicaciones para móviles. Para ello se midieron la distancia en metros al inicio del estudio y a los 3 meses de realizar ejercicio. Resultados. La mejoría de la claudicación antes y tras los 3 meses de tratamiento es de 108.75 metros en el grupo control y 146.25 metros en el grupo experimental, aunque resultando no significativa. Se confirma de forma significativa la mejoría en la distancia de claudicación al abandonar el habito tabáquico y al realizar tratamiento con cilostazol. Conclusiones. El uso de aplicaciones para móviles parece que mejora la adherencia al ejercicio de pacientes con enfermedad arterial periférica, aunque son necesarios más estudios para confirmarlo. Se puede afirmar que el uso adecuado del cilostazol y el abandono del tabaco son un tratamiento eficaz en cuanto a la mejora de la distancia sin claudicación.[Abstract] Purposes. The main point of this document is to demonstrate the usefulness of using mobile applications to improve exercise efficiency. Moreover, it is dealt with the description of risk factors for Peripheral Arterial Disease and confirm the efficacy of the use of cilostazol and smoking cessation making better the distance of claudication. Methodology. It is an experimental study, clinical trial, controlled, randomized, in parallel and not blind, carried out by the Angiology and Vascular Surgery service of the Virgen del Rocío Hospital with a duration of 10 months. According to practical research, those patients suffering from Grade II Peripheral Arterial Disease have been included in the Fontaine classification. Bearing all the above in mind, we consider a control group to be individuals who receive the usual instructions to perform home exercise and an experimental group to individuals who, in addition to the usual indications, are explained the use of mobile applications. Results. The improvement in claudication before and after 3 months of treatment is 108.75 meters in the control group and 146.25 meters in the experimental group, a distance that when applying the ANOVA test for one factor is not significant. Similarly, it occurs with the disabling distance with an improvement of 120 meters in the control group and 157.7 meters in the experimental group, being non-significant when using the ANOVA test for one factor. The enhancement in the distance of claudication is confirmed when quitting the smoking habit and when performing treatment with cilostazol. Conclusions. The use of mobile applications seems to improve adherence to the physical activity in patients with peripheral arterial disease, although more studies are needed to confirm this. Nevertheless, It can be affirmed that the proper use of cilostazol and smoking cessation are an effective treatment in terms of improving distance without claudication.[Resumo] Obxectivos. O obxectivo principal é demostrar a utilidade do uso de aplicacións móbiles para mellorar a eficiencia do exercicio. Como obxectivos secundarios: describir os factores de risco de Enfermidade Arterial Periférica e confirmar a eficacia do uso de cilostazol e o abandono tabáquico na mellora da distancia de claudicación. Metodoloxía. Trátase dun estudo experimental, ensaio clínico, controlado, aleatorizado, en paralelo e non cego, realizado polo servizo de Anxioloxía e Cirurxía Vascular do Hospital Virgen del Rocío cunha duración de 10 meses. Os individuos que padecen enfermidade arterial periférica de grao II foron incluídos na clasificación de Fontaine. Consideramos grupo control os individuos que reciben as instrucións habituais para realizar exercicios na casa e un grupo experimental aos individuos aos que, ademais das instrucións habituais, se lles explica o uso de aplicacións móbiles. Resultados. A mellora da claudicación antes e despois de 3 meses de tratamento é de 108,75 metros no grupo control e de 146,25 metros no grupo experimental, unha distancia que ao aplicar a proba ANOVA para un factor non é significativa. Do mesmo xeito, ocorre coa distancia de inhabilitación cunha mellora de 120 metros no grupo control e 157,7 metros no grupo experimental, sendo non significativo cando se utiliza a proba ANOVA para un factor. A mellora da distancia de claudicación confírmase ao deixar o hábito tabaquismo e ao realizar un tratamento con cilostazol. Conclusións. O uso de aplicacións móbiles parece mellorar a adhesión ao exercicio en pacientes con enfermidade arterial periférica, aínda que son necesarios máis estudos para confirmalo. Pódese afirmar que o uso axeitado do cilostazol e o abandono tabáquico son un tratamento eficaz en canto á mellora da distancia sen claudicación.Traballo fin de mestrado (UDC.FCS). Asistencia e investigación sanitaria. Especialidade en investigación clínica. Curso 2021/202

An optical investigation of Fischer-Tropsch diesel and Oxymethylene dimethyl ether impact on combustion process for CI engines

[EN] Synthetic fuels (E-fuels) have shown to be an interesting alternative to replace the fossil diesel fuel due to its CO2 reduction potential as well as for their capability to diminish the soot production and therefore for improving the soot-NOX trade-off in Compression Ignition engines. Thus, the main objective of this paper was to better understand the combustion process and the in-cylinder soot formation of two of the most popular E-fuels currently: Fischer-Tropsch (FT) diesel and Oxymethylene dimethyl ether (OMEX). To achieve this aim, a single cylinder optical CI engine with a commercial piston geometry was used. Thee optical techniques (Natural Luminosity-NL, OH* chemiluminescence and 2-color pyrometry) were applied to analyze the combustion evolution and quantify the soot formation at different loads (1.5, 4.5 and 7.5 bar IMEP). OMEX presented the largest injection duration due to the low LHV. For the NL analysis, OMEX showed the lowest light intensity for the three loads tested, indicating a very low soot production. Despite of the low NL intensity, it presented the highest OH* chemiluminescence signal, indicating a higher presence of near-stoichiometric zones due to the high amount of oxygen. Regarding FT diesel, it showed a combustion behavior similar to the commercial diesel. NL, OH* and 2-color technique analysis indicated that for the three conditions tested, FT diesel presented lower soot production and a faster soot oxidation than commercial diesel.This work was partially funded by Generalitat Valenciana through the Programa Santiago Grisolia (GRISOLIAP/2018/142) program.Pastor, JV.; García Martínez, A.; Mico Reche, C.; De Vargas Lewiski, F. (2020). An optical investigation of Fischer-Tropsch diesel and Oxymethylene dimethyl ether impact on combustion process for CI engines. Applied Energy. 260:1-12. https://doi.org/10.1016/j.apenergy.2019.114238S112260Benajes, J., García, A., Monsalve-Serrano, J., & Lago Sari, R. (2018). Fuel consumption and engine-out emissions estimations of a light-duty engine running in dual-mode RCCI/CDC with different fuels and driving cycles. Energy, 157, 19-30. doi:10.1016/j.energy.2018.05.144Dronniou, N., Kashdan, J., Lecointe, B., Sauve, K., & Soleri, D. (2014). Optical Investigation of Dual-fuel CNG/Diesel Combustion Strategies to Reduce CO2 Emissions. SAE International Journal of Engines, 7(2), 873-887. doi:10.4271/2014-01-1313Tanov, S., Wang, Z., Wang, H., Richter, M., & Johansson, B. (2015). Effects of Injection Strategies on Fluid Flow and Turbulence in Partially Premixed Combustion (PPC) in a Light Duty Engine. SAE Technical Paper Series. doi:10.4271/2015-24-2455Zha, K., Busch, S., Warey, A., Peterson, R. C., & Kurtz, E. (2018). A Study of Piston Geometry Effects on Late-Stage Combustion in a Light-Duty Optical Diesel Engine Using Combustion Image Velocimetry. SAE International Journal of Engines, 11(6), 783-804. doi:10.4271/2018-01-0230Omari, A., Heuser, B., Pischinger, S., & Rüdinger, C. (2019). Potential of long-chain oxymethylene ether and oxymethylene ether-diesel blends for ultra-low emission engines. Applied Energy, 239, 1242-1249. doi:10.1016/j.apenergy.2019.02.035Hao, B., Song, C., Lv, G., Li, B., Liu, X., Wang, K., & Liu, Y. (2014). Evaluation of the reduction in carbonyl emissions from a diesel engine using Fischer–Tropsch fuel synthesized from coal. Fuel, 133, 115-122. doi:10.1016/j.fuel.2014.05.025Kook, S., & Pickett, L. M. (2012). Liquid length and vapor penetration of conventional, Fischer–Tropsch, coal-derived, and surrogate fuel sprays at high-temperature and high-pressure ambient conditions. Fuel, 93, 539-548. doi:10.1016/j.fuel.2011.10.004Rimkus, A., Žaglinskis, J., Rapalis, P., & Skačkauskas, P. (2015). Research on the combustion, energy and emission parameters of diesel fuel and a biomass-to-liquid (BTL) fuel blend in a compression-ignition engine. Energy Conversion and Management, 106, 1109-1117. doi:10.1016/j.enconman.2015.10.047Schemme, S., Samsun, R. C., Peters, R., & Stolten, D. (2017). Power-to-fuel as a key to sustainable transport systems – An analysis of diesel fuels produced from CO 2 and renewable electricity. Fuel, 205, 198-221. doi:10.1016/j.fuel.2017.05.061Lapuerta, M., Armas, O., Hernández, J. J., & Tsolakis, A. (2010). Potential for reducing emissions in a diesel engine by fuelling with conventional biodiesel and Fischer–Tropsch diesel. Fuel, 89(10), 3106-3113. doi:10.1016/j.fuel.2010.05.013Gill, S. S., Tsolakis, A., Dearn, K. D., & Rodríguez-Fernández, J. (2011). Combustion characteristics and emissions of Fischer–Tropsch diesel fuels in IC engines. Progress in Energy and Combustion Science, 37(4), 503-523. doi:10.1016/j.pecs.2010.09.001Jiao, Y., Liu, R., Zhang, Z., Yang, C., Zhou, G., Dong, S., & Liu, W. (2019). Comparison of combustion and emission characteristics of a diesel engine fueled with diesel and methanol-Fischer-Tropsch diesel-biodiesel-diesel blends at various altitudes. Fuel, 243, 52-59. doi:10.1016/j.fuel.2019.01.107Abu-Jrai, A., Tsolakis, A., Theinnoi, K., Cracknell, R., Megaritis, A., Wyszynski, M. L., & Golunski, S. E. (2006). Effect of Gas-to-Liquid Diesel Fuels on Combustion Characteristics, Engine Emissions, and Exhaust Gas Fuel Reforming. Comparative Study. Energy & Fuels, 20(6), 2377-2384. doi:10.1021/ef060332aSchaberg, P., Botha, J., Schnell, M., Hermann, H.-O., Pelz, N., & Maly, R. (2005). Emissions Performance of GTL Diesel Fuel and Blends with Optimized Engine Calibrations. SAE Technical Paper Series. doi:10.4271/2005-01-2187Iannuzzi, S. E., Barro, C., Boulouchos, K., & Burger, J. (2016). Combustion behavior and soot formation/oxidation of oxygenated fuels in a cylindrical constant volume chamber. Fuel, 167, 49-59. doi:10.1016/j.fuel.2015.11.060Pellegrini, L., Marchionna, M., Patrini, R., Beatrice, C., Del Giacomo, N., & Guido, C. (2012). Combustion Behaviour and Emission Performance of Neat and Blended Polyoxymethylene Dimethyl Ethers in a Light-Duty Diesel Engine. SAE Technical Paper Series. doi:10.4271/2012-01-1053Zhu, R., Wang, X., Miao, H., Huang, Z., Gao, J., & Jiang, D. (2008). Performance and Emission Characteristics of Diesel Engines Fueled with Diesel−Dimethoxymethane (DMM) Blends. Energy & Fuels, 23(1), 286-293. doi:10.1021/ef8005228Härtl, M., Seidenspinner, P., Jacob, E., & Wachtmeister, G. (2015). Oxygenate screening on a heavy-duty diesel engine and emission characteristics of highly oxygenated oxymethylene ether fuelOME1. Fuel, 153, 328-335. doi:10.1016/j.fuel.2015.03.012Omari, A., Heuser, B., & Pischinger, S. (2017). Potential of oxymethylenether-diesel blends for ultra-low emission engines. Fuel, 209, 232-237. doi:10.1016/j.fuel.2017.07.107Ma, X., Ma, Y., Sun, S., Shuai, S.-J., Wang, Z., & Wang, J.-X. (2017). PLII-LEM and OH* Chemiluminescence Study on Soot Formation in Spray Combustion of PODEn-Diesel Blend Fuels in a Constant Volume Vessel. SAE Technical Paper Series. doi:10.4271/2017-01-2329Liu, H., Wang, Z., Zhang, J., Wang, J., & Shuai, S. (2017). Study on combustion and emission characteristics of Polyoxymethylene Dimethyl Ethers/diesel blends in light-duty and heavy-duty diesel engines. Applied Energy, 185, 1393-1402. doi:10.1016/j.apenergy.2015.10.183Lumpp, B., Rothe, D., Pastötter, C., Lämmermann, R., & Jacob, E. (2011). OXYMETHYLENE ETHERS AS DIESEL FUEL ADDITIVES OF THE FUTURE. MTZ worldwide, 72(3), 34-38. doi:10.1365/s38313-011-0027-zLiu, H., Wang, Z., Wang, J., & He, X. (2016). Improvement of emission characteristics and thermal efficiency in diesel engines by fueling gasoline/diesel/PODEn blends. Energy, 97, 105-112. doi:10.1016/j.energy.2015.12.110Chen, H., Su, X., Li, J., & Zhong, X. (2019). Effects of gasoline and polyoxymethylene dimethyl ethers blending in diesel on the combustion and emission of a common rail diesel engine. Energy, 171, 981-999. doi:10.1016/j.energy.2019.01.089Payri, R., De La Morena, J., Monsalve-Serrano, J., Pesce, F. C., & Vassallo, A. (2018). Impact of counter-bore nozzle on the combustion process and exhaust emissions for light-duty diesel engine application. International Journal of Engine Research, 20(1), 46-57. doi:10.1177/1468087418819250De Simio, L., & Iannaccone, S. (2019). Gaseous and particle emissions in low-temperature combustion diesel–HCNG dual-fuel operation with double pilot injection. Applied Energy, 253, 113602. doi:10.1016/j.apenergy.2019.113602Denny, M., Holst, F., Helmantel, A., Persson, H., Tunestål, P., & Andersson, Ö. (2019). Impact of closely-coupled triple-pilot and conventional double-pilot injection strategies in a LD diesel engine. Fuel, 246, 141-148. doi:10.1016/j.fuel.2019.02.101Pastor, J. V., García-Oliver, J. M., García, A., & Pinotti, M. (2016). Laser induced plasma methodology for ignition control in direct injection sprays. Energy Conversion and Management, 120, 144-156. doi:10.1016/j.enconman.2016.04.086Jakob, M., Hülser, T., Janssen, A., Adomeit, P., Pischinger, S., & Grünefeld, G. (2012). Simultaneous high-speed visualization of soot luminosity and OH∗ chemiluminescence of alternative-fuel combustion in a HSDI diesel engine under realistic operating conditions. Combustion and Flame, 159(7), 2516-2529. doi:10.1016/j.combustflame.2012.03.004Pastor, J. V., García-Oliver, J. M., García, A., Micó, C., & Möller, S. (2016). 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Ovoid amphorae in the Mediterranean (2nd century BC- early 1st century AD). State of the play and future research perspectives

info:eu-repo/semantics/publishedVersio

Elimination of scan impedance anomalies in ultra-wide band phased arrays of differentially fed tapered slot antenna elements

Scan impedance anomalies are associated to phased arrays. There are different phenomena in order to explain these scan blindnesses produced when the array scans at one frequency and one angle. The most popular technique for eliminating these scan blindnesses is based on the use of electric walls in the grid of the two dimensional array. In this paper we present a dual polarized ultra-wide band array based on “bunny ears” antennas from 0.3 GHz to 1 GHz which presents scan blindness. We analyze the cause of the anomaly and present a technique non based on electric walls in order to avoid the scan blindness with a small increase in the noise figure of the array

Biochemical effects and polycyclic aromatic hydrocarbons (PAHs) in Senegal sole (Solea senegalensis) from a Huelva estuary (SW Spain).

Relations between several stress oxidative biomarkers and aromatic polycyclic hydrocarbon (PAH) concentrations have been studied in wild sole, Solea senegalensis collected in the vicinity of a petrochemical industry. Antioxidant enzyme activities in eco-toxicological studies constitute excellent markers for exposure to a large variety of pollutants. The 16 PAHs in sediment as well as oxidative damage (LPO), activity of catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and PAHs type metabolites in sole liver were analysed. Significant correlations (p<0.05) were established between some biomarkers as GST, GPx and CAT and PAHs metabolites in liver (naphthalene, pyrene and phenanthrene) and PAHs concentrations in sediments (fluoranthene, acenaphthene, anthracene and chrysene). PAHs accumulated in the sediment and organisms are inducers of antioxidant defences. GST, GPx and CAT were robust biomarkers showing correlations with both PAHs in sediments and liver PAH metabolites showing different responses to low and high molecular weight PAHs

EIFIS: a modular extreme integral field spectrograph for the 10.4m GTC

EIFIS (Extreme Integral FIeld Spectrograph) is a modular integral field spectrograph, based on image slicers, and makes use of new, large format detectors. The concept is thought to cover the largest possible field of view while producing spectroscopy over the complete optical range (3 000 - 10 000 \r{A}) at a medium resolving power of about 2400. In the optimal concept, each module covers a field of view of 38" x 38" with 0.3" spaxels, which is fed into a double spectrograph with common collimator optics. The blue arm covers the spectral range between 3000 and 5600 \r{A} and the red arm between 5400 and 10100 \r{A}, allowing for an overlap range. The spectra are imaged onto 9.2k x 9.2k detectors using a double pseudoslit. The proposed design for the 10.4m Gran Telescopio Canarias uses a total of 6 such modules to cover a total of 2.43 square arcminutes. Here we will present the conceptual design of the instrument and a feasibility study of the optical and mechanical design of the spectrographs. We discuss the limitations and alternative designs and its potential to produce leading edge science in the era of extremely large telescopes and the James Webb Space Telescope.Comment: Submitted to the Proceedings of the SPIE, Astronomical Telescopes and Instrumentatio

Mértola entre la Edad del Hierro y la Romanización: nuevos datos a partir de las excavaciones de la Biblioteca Municipal

Presentamos un avance de los resultados de un proyecto en curso sobre la ocupación de Mértola en un momento de transición clave para entender el devenir histórico de la ciudad, como son los últimos siglos de la Edad del Hierro y el inicio de la romanización. Se trata de un periodo poco representado en el registro arqueológico conocido y musealizado, si bien se conocía desde hace años a través de materiales residuales procedentes de niveles posteriores, como el periodo altoimperial, tardoantiguo o medieval islámico. No obstante, las excavaciones realizadas a mediados de la pasada década en el solar de la Biblioteca Municipal han permitido documentar contextos primarios de finales de la Edad del Hierro y potentes depósitos de vertidos extramuros correspondientes a los primeros momentos de la presencia romana. Las evidencias proporcionadas ofrecen la oportunidad de estudiar en profundidad esta fase tan poco conocida de la antigua Myrtilis y conocer la dinámica comercial de su importante puerto.Apresentamos os resultados preliminares de um projecto em curso sobre a ocupação de Mértola num momento de transição fundamental para entender o devir histórico da cidade nos últimos séculos da Idade do Ferro e o início da romanização. Trata-se de um período pouco representado no registo arqueológico conhecido e musealizado, apesar de ter vindo a ser identificado entre os materiais residuais provenientes de níveis posteriores, nomeadamente dos períodos alto-imperial, tardo-antigo ou medieval islâmico. Não obstante, as escavações realizadas em meados da década passada na área de expansão da Biblioteca Municipal de Mértola permitiram documentar contextos primários datáveis do fim da Idade do Ferro e potentes depósitos de despejo extramuros correspondentes aos primeiros momentos da presença romana. As evidências proporcionadas constituem uma oportunidade para estudar em profundidade esta fase tão pouco conhecida da antiga Myrtilis e conhecer a dinâmica comercial do seu importante porto.info:eu-repo/semantics/publishedVersio

Proline content of sugar beet storage roots: Response to water deficit and nitrogen fertilization at field conditions

Drought stress is one of the major factors causing profit loss of the sugar beet crop. The accumulation of proline, an indicator of water stress, has been reported in response to osmotic and salt stress in sugar beet leaves, but there is little information about its levels in storage roots. Proline in storage roots is potentially useful as indicator of situations that lead to decreased yield and quality of the root, such as drought stress and excess nitrogen. This study has been focused towards proline quantification in storage roots from field trials concerning irrigation, sugar beet variety and nitrogen fertilization. Water deficit is the main factor leading to proline accumulation in sugar beet roots. Excess N supply also increases proline levels, partially by increasing leaf area index (LAI) and exacerbating drought stress. The two varieties studied (Claudia and Ramona) had different responses to water shortage and to nitrogen. Maximum proline levels were measured in Claudia roots subjected to a combination of water shortage and excess N. A positive and significant correlation was found between proline and glucose levels in sugar beet roots, pointing to a relationship between stress responses, carbohydrate catabolism, and proline and glucose accumulation. This proposal was supported by the effect of treatments with di-1-p-menthene (anti-transpirant) and with DMDP (2,5-dihydroxymethyl-3,4-dihydroxypyrrolidina, a glycosidase inhibitor), which lead to decreased level of proline in non-irrigated Claudia sugar beet roots.Subdirección General de Proyectos de Investigación Científica y Técnica de España y FEDER (Unión Europea) IFD97-0893-CO3-01Universidad de Sevilla USE-MONTE P-96Junta de Andalucía (PAI) CVI 29

Sistema de enfoque basado en dos espejos elípticos y un espejo plano rotatorio para un radar a 300 GHz

A focusing system for a 300 GHz radar with two target distances (5m and 10m) is proposed, having 1cm resolution in both cases. The focusing system is based on a gaussian telescope scheme and it has been designed using gaussian beam quasi-optical propagation theory with a homemade Matlab analysis tool. It has been translated into a real focusing system based on two elliptical mirrors and a plane mirror in order to have scanning capabilities and validated using the commercial antenna software GRAS