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2017-12-08
Paper
SN-0003
Small tactical UAVs (SUAVs) have made their mark in military operations with their ability to gather and provide localized, real-time information. Typical uses include perimeter surveillance of remote military compounds, over-the-horizon surveillance, and remote monitoring of critical logistics routes. However, their potential to take on increased and increasingly complex missions is hampered by their limited endurance. This work explores research done under the auspices of the European Commission’s Fuel Cell and Hydrogen Joint Undertaking on a fuel cell and battery hybrid energy storage system that could increase the total amount of onboard energy storage, while continuing to deliver the peak power needs of the SUAV.
2017-11-15
Journal Article
2017-32-0119
Akira Iijima, Takuya Izako, Takahiro Ishikawa, Takahiro Yamashita, Shuhei Takahata, Hiroki Kudo, Kento Shimizu, Mitsuaki Tanabe, Hideo Shoji
Engine knock is the one of the main issues to be addressed in developing high-efficiency spark-ignition (SI) engines. In order to improve the thermal efficiency of SI engines, it is necessary to develop effective means of suppressing knock. For that purpose, it is necessary to clarify the mechanism generating pressure waves in the end-gas region. This study examined the mechanism producing pressure waves in the end-gas autoignition process during SI engine knock by using an optically accessible engine. Occurrence of local autoignition and its development process to the generation of pressures waves were analyzed under several levels of knock intensity. The results made the following points clear. It was observed that end-gas autoignition seemingly progressed in a manner resembling propagation due to the temperature distribution that naturally formed in the combustion chamber. Stronger knock tended to occur as the apparent propagation speed of autoignition increased.
2017-11-15
Journal Article
2017-32-0120
Go Asai, Yusuke Watanabe, Shuntaro Ishiguro, Gen Shibata, Hideyuki Ogawa, Yoshimitsu Kobashi
To extend the operational range of premixed diesel combustion, fuel reformation by piston induced compression of rich homogeneous air-fuel mixtures was conducted in this study. Reformed gas compositions and chemical processes were first simulated with the chemistry dynamics simulation, CHEMKIN Pro, by changing the intake oxygen content, intake air temperature, and compression ratio. A single cylinder diesel engine was utilized to verify the simulation results. With the simulation and experiments, the characteristics of the reformed gas with respect to the reformer cylinder operating condition were obtained. Further, the thermal decomposition and partial oxidation reaction mechanisms of the fuel in extremely low oxygen concentrations were obtained with the characteristics of the gas production at the various reaction temperatures.
2017-11-13
Tech Insights
TI-0002
While all-electric aircraft remain at the bleeding edge of the aviation industry, incorporating technologies like proton exchange membrane fuel cells into existing aircraft can result in considerable auxiliary capability with low environmental impact. However, proper consideration must be given to supporting systems to achieve a reliable balance of plant-especially when those systems interface with existing aircraft architectures. The scope of the BoP is to manage and condition the reactant flows to and from the fuel-cell module and to provide power to system components.
2017-11-07
Technical Paper
2017-36-0109
Haraldo Rehder, Gustavo P. Rehder
Abstract Environmental damage and climate change, air pollution, energy efficiency, fuel consumption and emissions are subjects for studies and legislations worldwide. Brazil must therefore be prepared to follow global trends in energy optimization tests and developments, including Euro 6 equivalent emission legislation. Considering the worldwide tendency for Real Driving Condition Test for heavy vehicles, the authors, using the developed Towing Trailer Prototype provided with an electromagnetic brake, performed fuel consumption on-road tests. For measuring fuel consumption on-road or on testing tracks, the developed system allows initially measurements with an independent auxiliary tank for short distances and measurement with an auxiliary tank connected with the truck tank for long distances. The tests were performed on road in real conditions initially by maximum speeds of 75 km/h.
2017-11-07
Technical Paper
2017-36-0095
Arthur Braga Thiriet, Fabrício José P. Pujatti, Paulo César S. Araújo
Abstract Resistive forces are a great source of fuel consumption in vehicles. In particular, rolling resistance represent the major resistance force at low speeds. It is highly influenced by the inflation pressure of the tire and vertical load over it. In the present work, a computer model is created with the objective of investigating the influence of tire inflation pressure on fuel consumption and rolling resistance force. Pressure is varied and parameters analyzed at different vehicle speeds for two different calculation methods. Results show significant decrease in fuel consumption and rolling resistance force as inflation pressure is augmented.
2017-11-07
Technical Paper
2017-36-0084
Ricardo Gonçalves, Fabio Ferraz
Abstract Currently in Brazilian market we have application of two different fuels in large scale, gasoline with addition of 27% of hydrous ethanol, otherwise known as ethyl alcohol or alcohol and pure hydrous ethanol. These different fuels and their various blends combinations - from 27% (E27) to 100% (E100) of ethanol - make the gases from combustion have different physical characteristics, affecting directly the exhaust system acoustic performance. This study is going to describe the physical differences of the exhaust gases with various blends combination and their respective impact on the exhaust system acoustic performances.
2017-11-07
Technical Paper
2017-36-0147
Clayton B. Zabeu, Luana C. X. Camargos, Luiz Rafael Marinsek, Rafael C. R. Berti, Renan L. Nicola, Rafael Serralvo Neto
Abstract The need to reduce greenhouse gas emissions by the automotive sector has demanded an increase in the efficiency of internal combustion engines as well as the use of renewable fuels, with ethanol being one of the most promising fuels. In SI PFI engines, the quality of the air-fuel mixture formed during the injection event is dependent on several factors, such as: physical-chemical properties of the fuel (density, viscosity, surface tension, latent heat of vaporization), interaction between fuel spray and gas flow / pipe walls / back surfaces the intake valves.
2017-11-07
Technical Paper
2017-36-0142
Fábio Coelho Barbosa
Abstract The aviation industry currently holds a share of 2% global greenhouse gas (GHG) emissions. Although relatively small, estimated demand increase indicates an up to 350% emission rise in 2050, in the so called “no action scenario”. These emissions are injected into the upper atmosphere, with a potentialized stronger greenhouse effect than at ground level. In this context, ambitious emission reduction targets have been proposed into a global commitment, focused into a long term carbon emission reduction strategy, which would lead to net GHG emissions to peak in 2020, and then halves by 2050, based on 2005 levels, while accommodating increased air transport demand. To achieve this challenging goal, a multifaceted approach is required, ranging from technology oriented actions, like revolutionary aerodynamically driven design, new composite lightweight material and engine technology improvement, as well as improved ground and flight operational practices.
2017-11-07
Technical Paper
2017-36-0387
Ciro Galvão, Eduardo Tomanik, Hiroshi Fujita, Eliel Paes, Paulo Morais
Abstract Low viscosity combined with appropriated additive technology is one of the main paths to reduce friction on Internal Combustion Engines. Japan is on the cutting edge of low viscosity oils, having already available SAE 0W-8 in the market. On the other hands, in emergent countries like Brazil, SAE 15W-40 is still used in some passenger cars while the Japanese origin car brands use SAE 0W-20. Lubricant friction additives type also differs depending on the original equipment manufacturer (OEM) origin, and the Japanese ones usually containing high amounts of the Molybdenum type. In this paper, some of the advantages and challenges of using low viscosity oils are discussed and emphasis is given in the friction reduction obtained with the synergic effects of the right choice of additives components type and the material/coating used in the engine parts. Ring-liner rig and floating liner engine tests comparing different oils will be presented.
2017-11-07
Technical Paper
2017-36-0388
Fernanda Pinheiro Martins, Santiago Daniel Martinez Boggio, Pedro Texeira Lacava, Claudia Regina de Andrade, Alexander Penaranda, Maycon Ferreira Silva, Maria Esther Sbampato
Abstract In the last few decades a significant effort has been stablished in the automotive industry as well as in academic community towards increasing the renewable fuels applications in internal combustion engines, such as alcohol and gas derived sources. Meanwhile, turbo charging direct-injection spark-ignition engines have become fundamental features to achieve downsizing purposes, increasing power generation efficiency and attending high restrictive emissions regulations that have being taking place recently. For this study, experimental tests were carried out in a single cylinder research engine considering direct injection (DI) and port fuel injection (PFI) operations with anhydrous ethanol. The aim of this paper is to present a review and conduct further investigation about methodologies applied for imaging post processing considering chemiluminescence technique applied in an optical research engine.
2017-11-07
Technical Paper
2017-36-0389
G. R. Sanchez, T. R. L. Santos, Y. C. Pereira, A. V. N. Dias, F. Malvezzi
Abstract Worldwide, there is a popular charge for equipment and processes that have an ecological responsibility, aiming the preservation of the environment. That charge comes specially in the automotive industry, due to the emission of harmful gases to the health, provoked by the burn of fossil fuel, being directly correlated with the fuel consumption of the vehicle. Although the automotive researches have worked to increase the vehicle autonomy, the driver behavior has influence on the vehicle fuel consumption, due their involvement with vehicle components maintenance. Moreover, nowadays there is a large effort by the automobile industry and their suppliers to use software to simulate real test, aiming to reduce the outdoor test. This work aims to analyses the influence of parameters that can be controlled by the driver on the fuel consumption.
2017-11-07
Technical Paper
2017-36-0247
Fernando de Oliveira Junior, Isaac Gentini, Fernando Lepsch, Alex Siegle, Guilherme Torres Ferreira
Abstract The first generation of heated cold start systems for flex fuel vehicles in Brazil were launched in 2009 and have solved most of the issues around the former gasoline sub-tank concept. This new technological approach focused on concerns like the user experience by having the need to fulfill the sub-tank, on complains related to possible old gasoline left inside, in the complexity of the electro mechanic nozzles and other possible improvements. Some years later, the second generation expanded the initial cold start application to a mature drivability enhancement and further possibility of usage as a support for emission reduction. A leaner electronic control and heat sink concept also represented an alternative to the first generation, and an engineered plastic fuel rail replaced the first metallic concept, which was an option to the initial concerns about the combination of high temperatures and fuel.
2017-11-07
Technical Paper
2017-36-0259
Thiago R. V. Silva, José G. C. Baeta, Nilton A. D. Neto, Augusto C. T. Malaquias, Matheus G. F. Carvalho, Fernando R. Filho
Abstract The current energy and climate world condition presents the need for development of increasingly efficient and sustainable internal combustion engines. In order to meet these requirements, environmental regulatory agencies establish long-term goals of fuel consumption and pollutant gases emissions reduction, which in turn lead the engines to a constant evolution. Thus, this work exploits some recent technologies that tend to minimize the environmental impact of the world’s extensive automotive fleet. Among them, direct injection systems, especially with the use of biofuels, such as ethanol, allow the engine to operate under lean stratified conditions through split-injection. This strategy consists to split several times the fuel injection phase, so that an injection portion can be performed at the intake stroke and the other injection portion at the compression stroke.
2017-11-07
Technical Paper
2017-36-0266
Thiago R. V. Silva, José G. C. Baeta, Nilton A. D. Neto, Augusto C. T. Malaquias, Matheus G. F. Carvalho, Fernando R. Filho
Abstract The abnormal combustion, such as pre-ignition and knock, are deviations from the controlled combustion process under certain operating conditions, which can result in performance losses and possible damage to the engine. In the SI engines, a pre-ignition event can take place when the flame front is started by any hot spot into the combustion chamber before ignition by the spark plug. The objective of this work is to investigate the use of the Stratified Combustion for Pre-Ignition Suppression (SCPIS) in order to reduce this undesirable phenomenon, especially under high load operating conditions. The results were obtained through dynamometric tests on a downsized ethanol SIDI engine, and considered satisfactory in terms of maximizing the fuel conversion efficiency.
2017-11-07
Technical Paper
2017-36-0264
Thiago R. V. Silva, José G. C. Baeta, Nilton A. D. Neto, Augusto C. T. Malaquias, Matheus G. F. Carvalho, Fernando R. Filho
Abstract The downsized ethanol Spark Ignited Direct Injection (SIDI) engine has proven to be one of the most promising concepts to reduce both the fuel consumption and pollutant emissions. In addition to this engine concept, the use of Fully Variable Camshaft Timing (FVCT) can provide the Internal Exhaust Gas Recirculation (I-EGR) into the combustion chamber. The Cooled Exhaust Gas Recirculation (Cooled - EGR) technique, has been adopted in order to reduce the NOx formation rate. However, through the FVCT system, acceptable levels of charge dilution by I-EGR can be achieved resulting in less fuel consumption and pollutant emissions. In this paper, the I-EGR technique has been investigated by carrying out an experimental analysis of a downsized ethanol SIDI engine running on boosted and unboosted conditions. The results at part load operation present a gain on fuel conversion efficiency due to the I-EGR dilution and the use of de-throttling technique.
2017-11-07
Technical Paper
2017-36-0272
Victor Hugo de Castro Lima, Carlos Alberto Gomes Júnior, Márcio Expedito Guzzo, Thiago Rodrigo Vieira da Silva, José Guilherme Coelho Baeta, Fernando Antonio Rodrigues Filho
Abstract The growing demand for more efficient and less polluting engines has lead the scientific community to further develop the road map engine technologies, including direct fuel injection. Direct injection research demands the investigation of spray formation and its characteristics. The present work performs the characterization of the macroscopic parameters of ethanol sprays (E100) produced with a fuel gauge pressure of 80 bar and gauge back pressures of 0, 5 and 10 bar. The sprays analysis was performed using high speed filming by means of Shadowgraph technique. Computational routines of matrix analysis were applied to measure the spray cone angles, penetration and penetration rate. The spray visualization demanded an experimental apparatus composed of a pressurized cylinder with nitrogen, a fuel tank as pressure vessel, an injection driver equipped with a peak and hold module controlled by a MoteC M84, a Phantom V7.3 high speed camera and LEDs for illumination.
2017-11-07
Technical Paper
2017-36-0291
Tiago Sinigaglia, Felipe Lewiski, Mario Eduardo Santos Martins
Abstract Fossil fuels are non-renewable resources of energy, being one of the largest fractions of the greenhouse gases (GHG). Hydrogen is indicated as a fuel with potential to replace fossil fuels in the future, mainly because the combustion products are environmentally friendly, with high specific energy, in comparison with other sources of fuel. However, to use hydrogen as a fuel in internal combustion engines (ICE) or in fuel cell vehicles (FCV), it is necessary to separate it from primary elements (water, biomass, natural gas, etc.). It´s also need to consider storage and transport in order to handle a fuel like hydrogen. All of these phases require energy, which may be from renewable or non-renewable sources, causing environmental impacts. In order to investigate if the hydrogen is economically viable, aspects such as environmental impacts, safety and technological feasibility need to be studied.
2017-11-07
Technical Paper
2017-36-0357
Karsten Wittek, Frank Geiger, Jakob Andert, Mario Martins, Maurício Oliveira
Abstract The possibility to vary compression ratio offers a new degree of freedom that may enable so far not exploited benefits for the combustion process especially for highly boosted spark ignited engines. Numerous approaches to enable a variable compression ratio (VCR) have been tried and tested in the past. Nevertheless, none of these systems reached series production because of several reasons, ranging from too much complexity and moveable parts to deep modification required on existing engine architectures and manufacturing lines. Instead, the approach of a variable length conrod (VCR conrod) could be the solution for integration in almost any type of engine with minor modifications. It is then considered by several OEMs as a promising candidate for midterm series production. This paper shows, firstly, a discussion of the benefits of a variable compression ratio system.
2017-11-07
Technical Paper
2017-36-0360
Raphael Meireles Braga, Marilia Gabriela Vaz, Clarissa de Moraes Martins, Gustavo Hindi, Rudolf Huebner
Abstract The fuel injection in internal combustion engines plays a crucial role in the mixture formation, combustion process and pollutants' emission. Its correct modeling is fundamental to the prediction of an engine performance through a computational fluid dynamics simulation. In the first part of this work a tridimensional numerical simulation of a multi-hole’s injector, using ethanol as fuel, is presented. The numerical simulation results were compared to experimental data from a fuel spray injection bench test in a quiescent vessel. The break up model applied to the simulation was the combined Kelvin-Helmholtz Rayleigh-Taylor, and a sensitivity analysis of the liquid fuel penetration curve, as well on the overall spray shape was performed according to the model constants. Experimental spray images were used to aid the model tuning. The final configuration of the KH-RT model constants that showed best agreement with the measured spray was C3 equal to 0.5, B1, 7 and Cb, 0.
2017-11-07
Technical Paper
2017-36-0359
Santiago Daniel Martinez Boggio, Pedro Texeira Lacava, Maycon Ferreira Silva, Maria Esther Sbampato, Leila Ribeiro Santos, Alexander Peñaranda, Pedro Luiz Curto Risso
Abstract Pressures on vehicle manufacturers to reduce emissions have resulted in an increased interest to improve fuel economy and enable use of fuels developed from renewable sources that can achieve a net reduction in the CO2 output per vehicle. The use of bio-gas fuels in internal combustion engines has become a real alternative to traditional liquid fuels derived from petroleum. To extract the maximum benefits from these emergent fuels through optimized engine design and calibration, a deep understanding of the behavior is necessary. The combustion process of a single cylinder research engine with optical access, four stroke PFI-SI, was experimentally investigated. High spatial resolution cycle resolved digital imaging, in the visible and UV spectral range was used to characterize the flame front propagation.
2017-11-07
Technical Paper
2017-36-0159
Alberto K. Watanabe, Alexandre Carriao, Carlos H. Pascon, Marisa Kikuchi
Abstract The development of fuel systems components are becoming challenging with the increasing use of Biofuels like Biodiesels and Ethanol around the world. Biodiesels are one of the most challenging fuels, once they can have multiple sources, which influences its characteristics, mainly the oxidization stability and peroxide levels. As the fuel characteristics changes along the time, the correct materials selection during the development phase is very important for the fuel system performance during the vehicle lifetime. One of the components most affected by the Biodiesel is the in tank fuel pump system. During the vehicle lifetime, it is exposed to all sorts of fuel and its contaminants and exposed to system stress factors like temperature and voltage variation. The wires insulation in the fuel pump systems are one of the most affected components.
2017-11-07
Technical Paper
2017-36-0162
Paulo César de Ferreira Gomes, Carlos Fernando Mendes, Gustavo Santos Lopes, Erwin Karl Franieck, Alysson Fernandes Teixeira, José Guilherme Coelho Baeta, Nilton Antônio Diniz Netto
Abstract Recently many government Acts (Inova Energia, Inovar-Auto, RenovaBio) [1, 2, 3] have been implemented in order to expand the use of biofuels in Brazil. Besides the fulfillment until 2030 of the commitment assumed at the COP21[4] to reduce in 43% the gas emission contributing to the greenhouse effect, the expansion of the use of biofuels is important to assure regularity in the supply of fuels to the automotive sector in the next 15 years. In this context, it is worth mentioning a special characteristic of the Flex-Fuel engines that equip the majority of the automobiles in Brazil since their launching in 2003. The maximum compression ratio of these engines depends on the knocking characteristics of the gasoline, but usually an intermediate value, nearer to the ideal value for gasoline, is a compromise.
2017-11-07
Technical Paper
2017-36-0167
Alvaro Cesar Garcia, Cleber William Gomes
Abstract The turbocharger has unleashed a new era of highly efficient internal combustion engines and shows the right technology to meet global emissions laws. With a simple concept, the turbocharger can reduce the specific fuel consumption, increase engine power and torque by increasing its volumetric efficiency. By using the energy contained in the exhaust gases, the turbocharger compresses the atmospheric air, increasing its density, so that at the moment of combustion there is a more efficient burning of the fuel injected. The purpose of this paper is to analyze the internal components of the turbocharger and a computer simulation made in Ricardo Software's Waves to analyze differences in fuel consumption, volumetric efficiency, torque and in the power of a turbocharged engine compared to the same engine, but without the turbocharger installed.
2017-11-07
Technical Paper
2017-36-0199
R Lopes, A Carbonara
Abstract Vehicle Fuel Economy and Emission measurements requires road load determination by standardized Coast-down test. Worldwide stablished standards for testing and calculation apply second order polynomial fit models to describe road load. The common approach on road load analysis and validation is by direct comparison of coefficients and corresponding parabolas. This paper discuss an alternative approach (currently used by the USA Environmental Protection Agency) for estimating road load energy loss on standard test driving profile. Combining simple physical concepts on Work with the road load model and the chassis dynamometer driving profile, equations are derived describing the energy loss as a function of road load coefficients on a fuel economy test.
2017-11-07
Technical Paper
2017-36-0208
Rafael L. Sari, Diego Golke, Henrique J. Enzweiler, Kelvin F. Santos, Nina P. G. Salau, Mario E. S. Martins, Fernando M. Pereira
Abstract Hydrous ethanol is pointed out as one of the major alternative fuel for internal combustion engines, because it is environmental friendly (almost zero CO2 emission) and has excellent combustion properties. Recent studies have shown that ethanol-water fuel blends with higher water content (so-called wet ethanol) can reduce the overall costs of ethanol production. The use of wet ethanol results in lower nitrogen oxides emissions at the cost of reduced lower heating value per mass of fuel blend, which may result in less thermal efficiency. On the other hand, the increase in water content improves knock resistance. Thus, this study aims to investigate the effects of mechanical compression ratio variation on a spark ignition engine using ethanol-water fuel blends containing 4, 10, 20 and 30% v/v of water in ethanol. The research was carried out in a SI single cylinder engine, port fuel injected, 0.668 dm3 with the compression ratio modified by spacer rings.
2017-11-07
Technical Paper
2017-36-0215
Felipe V. Lewiski, Edson Bazzo, Mario E. S. Martins, Paulo R. M. Machado, Jácson Antolini, Geovane A. F. Prante, Vitor V. Cogo
Abstract Vegetable oils have been seen as promising surrogates to petroleum diesel in compression ignition internal combustion engines, showing similar performance and combustion characteristics of the fossil fuel. Nevertheless, the use of straight (crude) vegetable oil (SVO) is unfavorable due to its high viscosity, which affects the Sauter Mean Diameter of fuel spray and, consequently, fuel-air mixing process, resulting in incomplete combustion. The SVO heating, as well as transesterification and blending with diesel or additives, are some of the techniques to reduce its viscosity and enable its use. Of these the most simple and direct is the heating and was used in this paper to evaluate the performance and emissions of a diesel engine fueled with preheated soybean oil (PSO) by electrical resistances. The experiments were carried out in a single cylinder four-stroke compression ignition engine with mechanical fuel injection.
2017-11-07
Technical Paper
2017-36-0236
Claudio M. Engler Pinto, Victor Algate, André Carbonara
Abstract The first production ethanol (E100) fueled capable vehicle was launched in Brazil in 1979. In the decade of 1980, most of the vehicles in Brazilian market ran either on gasohol (E22) or on ethanol. By this time, two different engine hardware had been developed: one for gasohol and one for ethanol, the latter with a higher compression ratio assuring a better fuel conversion efficiency. In this period, it was usual to have same vehicle models operating with an E100 / E22 fuel economy ratio (FE in km/l) in the range of 0.75 to 0.80. This range is greater than the E100 / E22 energy content ratio which is approximately 0.70. The customers very well perceived the higher efficiency of the ethanol-fueled vehicle when the low E100 / E22 price ratio at the pump played a major factor for this perception.
2017-11-07
Technical Paper
2017-36-0241
Renato Souza, Carlos Carvalho, Rosalvo Bertolucci
Abstract The identification of fuel blends using software strategies and the oxygen sensor are widely known for flex fuel and naturally aspirated engines in Brazil, since its first launch in 2003. It represents a cost effective alternative to identify the ethanol content in the fuel, which is being used in the combustion, with an accurate performance and reduced complexity. With the introduction of flex fuel vehicles equipped with turbocharger, especially the ones with Direct Injection (DI) technology, an ethanol sensor as an additional product has been used so far to identify the ethanol content in the fuel blend. Such engine types may be more sensitive to fuel mixture deviations, since it works with higher loads, more combustion chamber pressure and an extended temperature range in comparison with the normally aspirated applications. Due to these reasons, worst-case scenarios with high ethanol content deviation could cause damage to the engine and exhaust hardware.
2017-11-07
Technical Paper
2017-36-0110
Giovanne Davanço Cosme, Juliana Soares Leite Martins, Charles Correa Conconi
Abstract Absorbent blankets are used to control engine and diesel oil leaks, which in turn are the main problems encountered in the automotive industry, and may lead to contamination in groundwater, rivers sheets. In order to meet increasingly restrictive environmental requirements, as well as to mitigate the environmental impacts that may be caused by spills or leaks, it is necessary to use efficient absorbent blankets, as well as their composition. To evaluate efficiency and certify the choice of blanket, a simple methodology has been developed that can have results quickly. This work shows a methodology that uses equipment normally found in the laboratory, such as Analytical balance with three decimal precision, Petri dish, Becker, Buchner funnel.
Viewing 1 to 30 of 16692