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Abstract This paper investigates the impacts of CO2 tax schemes on CO2 emissions, equity and macroeconomic indicators in Austria with the macroeconomic model DYNK[AUT]. Our scenarios focus on non-ETS CO2 emissions and comprise different tax rates and revenue recycling options (lower labor taxes, lower VAT and lump sum payments). The short-term comparative scenario analysis indicates that CO2 taxes without recycling lead to significant CO2 emission reductions at moderate economic costs. Equity impacts on households depend on the indicator used but can be regressive without recycling. Most recycling schemes can achieve a double dividend, i.e. emission reductions and increases in GDP. Lump sum payments are less efficient than reducing the VAT or labor taxes. Equity impacts are progressive with lump sum payments, rather proportional with lower VAT and regressive with lower labor taxes. A combination of recycling schemes and/or a restriction of lump sum payments to lower income households can minimize the trade-off between equity and efficiency. Our simulations suggest that well-designed CO2 tax schemes could be a crucial and socially acceptable element within a comprehensive policy package to achieve GHG emission targets for non-ETS sectors in Austria.

Abstract This work reports the drag coefficients (Cd) for three wind directions measured in low turbulence flow and in turbulent flow with characteristics of the atmospheric boundary layer wind, and the Strouhal numbers (St) of an approximately trapezoidal flanged section, used in the boom girder of a 100 m high port crane. These experimental results were obtained at the Boundary Layer Wind Tunnel of the Dept. Aeronautica at the Universidad Nacional de La Plata, in the range of Reynolds numbers between 30,000 and 180,000. The drag coefficients in the three studied directions showed a reduction for turbulent flow. Further measurements were carried out for the model with an inclination of 80° relative to the flow direction, the position of the crane boom when out of service, giving practically the same drag coefficients.

This work is carried out within the FP7 European research project TOICA (Thermal Overall Integrated Conception of Aircraft, http://www.toica-fp7.eu/). One of the tasks foreseen for the TOICA project is the analysis of fuel tanks as possible heat sinks for future aircrafts. In particular, in the present paper, commercial regional aircraft is considered as case study and CFD analysis with the commercial code STAR-CCM+ is performed in order to identify the potential capability to use fuel stored in the tanks as a heat sink for waste heat dissipated by other systems. The complex physical phenomena that characterize the heat transfer inside liquid fuel, at the fuel-ullage interface and inside the ullage are outlined. Boundary conditions, including the effect of different ground and flight conditions, are implemented in the numerical simulation approach. The analysis is implemented for a portion of aluminium wing fuel tank, including the leading edge effects. Effect of liquid fuel transfer among different tank compartments and the air flow in the ullage is included. According to Fuel Tank Flammability Assessment Method (FTFAM) proposed by the Federal Aviation Administration, the results are exploited in terms of exponential time constants and fuel temperature difference to the ambient for the different cases investigated.

Os resultados do estudo comparativo entre os dados observados em duas torres anemométricas instaladas no estado de Alagoas, com estimativas de vento produzidas em simulações numéricas realizadas com o modelo de mesoescala BRAMS, são apresentados e discutidos com o intuito de investigar a influência do refinamento da resolução horizontal e do aninhamento de grades na confiabilidade das estimativas de vento. As torres estavam instaladas em regiões de características distintas do ponto de vista ambiental e climatológico. Análises estatísticas foram realizadas para avaliar o desempenho do modelo no que se refere à capacidade de fornecer estimativas de vento que reproduzam a evolução temporal, o ciclo médio diário e a distribuição de frequência do vento observado nas duas localidades. O estudo foi realizado para as duas estações sazonais características da região: estação chuvosa (Maio/2008) e seca (Novembro/2008). Os resultados mostraram que houve um aumento na confiabilidade das estimativas da velocidade do vento quando a resolução horizontal passou de 8 km para 2 km. O ganho em confiabilidade foi mais significativo em Girau do Ponciano (GRP) localizada no interior do estado e que sofre menor influência do fenômeno de brisa marítima. O aumento da resolução horizontal para valores abaixo de 2 km não produziu redução importante dos desvios observados na estimativa da velocidade do vento pelo modelo na configuração adotada neste estudo. Os resultados demonstram a importância da aquisição de dados de campo para a investigação da confiabilidade, e ajuste das configurações e parametrizações inseridas em modelos numéricos, utilizados para estimar ou preReliability evaluation of wind regime estimates provided by the brams model for alagoas state (brazilian northeastern region): influence of nesting and horizontal resolution gridsver a disponibilidade de energia eólica em uma região específica.

The present work presents an experimental investigation of the jet flow produced by a blowing system for boundary-layer control at the test section of a low-speed wind tunnel. The main objective is to verify the flow uniformity at the system exit. The air jet leaving the apparatus was varied by changing the exit jet thickness as well as its inclination. The first measurements showed a very significant flow distortion. After a through and systematic work the desired flow uniformity was obtained.

[EN] Research efforts in the automotive sector focus on developing new combustion concepts for mitigating the emissions of nitrous oxides and soot of conventional Diesel combustion. One of the most promising concept is the Premixed Charge Compression Ignition. In this, the fuel burns in premixed conditions, avoiding the formation of soot whereas nitrous oxides are controlled using large amounts of exhaust gas recirculation. Because of the premixed combustion, high fuel-burning velocities are produced, whence combustion noise is deteriorated. In order to mitigate this drawback, different blends of gasoline and Diesel fuels are being considered due to their suitability for this combustion characteristics. The effect of these fuel blends on emissions, performance and engine noise is analysed in this paper with the aim to provide additional knowledge of the fundamental issues of this particular combustion mode. The study also includes sweeps of both the start of injection and the amount of exhaust gas recirculation, in order to evaluate further degrees of freedom in the optimisation of the engine settings. Results show that the consideration of the engine noise together with both performance and emissions, reduces dramatically the margin of variation of the combustion settings, limiting therefore the operation range of the engine. (C) 2017 Elsevier Ltd. All rights reserved. The equipment used in this work has been partially supported by the Spanish Ministerio de Economía y Competitividad through grant no DPI2015-70464-R and by FEDER project funds Dotación de infraestructuras científico técnicas para el Centro Integral de Mejora Energética y Medioambiental de Sistemas de Transporte (CiMeT), (FEDER-ICTS-2012-06) framed in the operational program of unique scientific and technical infrastructure of the Spanish Ministerio de Economía y Competitividad. J. Gomez-Soriano is partially supported through contract FPI-S2-2016-1353 of the Programa de Apoyo para la Investigación y Desarrollo (PAID-01-16) of Universitat Politècnica de València.

Agriculture is a critical domain, where technology can have a significant impact on increasing yields, improving crop quality, and reducing environmental impact. The use of renewable energy sources such as solar power in agriculture has gained momentum in recent years due to the potential to reduce the carbon footprint of farming operations. In addition to providing a source of clean energy, solar tracking systems can also be used for remote weather monitoring in the agricultural field. The ability to collect real-time data on weather parameters such as temperature, humidity, and rainfall can help farmers make informed decisions on irrigation, pest control, and other crop management practices. The main idea of this study is to present a system that can improve the efficiency of solar panels to provide constant power to the sensor in the agricultural field and transfer real-time data to the app. This research presents a mechanism to improve the arrangement of a photovoltaic (PV) array with solar power and to produce maximum energy. The proposed system changes its direction in two axes (azimuth and elevation) by detecting the difference between the position of the sun and the panel to track the sun using a light-dependent resistor. A testbed with a hardware experimental setup is designed to test the system’s capability to track according to the position of the sun effectively. In the end, real-time data are displayed using the Android app, and the weather data are transferred to the app using a GSM/WiFi module. This research improves the existing system, and results showed that the relative increase in power generation was up to 52%. Using intelligent artificial intelligence techniques with the QoS algorithm, the quality of service produced by the existing system is improved.

In this work, it was made a study of biodiesel synthesis by transesterification reaction from Jatropha Curcas Lineu Oil (“Mpuluka”) with methanol in the presence of NaOH. First of all a seed treatment and a granulometric study were carried out and it was concluded that the oil content and yield obtained from the extraction do not depend on the particles size of the seed. The Jatropha Curcas oil was obtained by means of a Soxhlet extraction system, using n -hexane. The oil content obtained was 45,32% and its yield was 90,88%. The physicochemical properties analysis of the oil indicates a high acidity index. For this, the synthesis of biodiesel was carried out using two steps: pre-treatment of crude oil before transesterification reaction and the esterification of crude oil followed by transesterification. The best yield in biodiesel (≈60%) was obtained with the molar ratio (oil/alcohol):1/6. The biodiesel obtained falls within admissible limit values of the international quality standards defined by ASTM_D and EN / ISO. In this work, it was made a study of biodiesel synthesis by transesterification reaction from Jatropha Curcas Lineu Oil (“Mpuluka”) with methanol in the presence of NaOH. First of all a seed treatment and a granulometric study were carried out and it was concluded that the oil content and yield obtained from the extraction do not depend on the particles size of the seed. The Jatropha Curcas oil was obtained by means of a Soxhlet extraction system, using n -hexane. The oil content obtained was 45,32% and its yield was 90,88%. The physicochemical properties analysis of the oil indicates a high acidity index. For this, the synthesis of biodiesel was carried out using two steps: pre-treatment of crude oil before transesterification reaction and the esterification of crude oil followed by transesterification. The best yield in biodiesel (≈60%) was obtained with the molar ratio (oil/alcohol):1/6. The biodiesel obtained falls within admissible limit values of the international quality standards defined by ASTM_D and EN / ISO.