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This work showed the use of alternative fuels as a means of generating energy using biodiesel based on frying oil through an evaluation and simulation of the fuel flow in the injectors of a MEP engine. With the application of the experimental method, tests were carried out on normal diesel, biodiesel with mixtures B10, B20 and B100 in the mechanical injectors to observe their opening pressure, closing time, spray angle and their dripping. With the data obtained from the tests in the laboratory, the statistical method was used to verify if they were in the usual operating range of the injectors to proceed with the simulation in ANSYS software, evaluating the behavior of the fluid inside the injector, in addition to obtain values of pressures and velocities in the flow of the fluid within it. In this way, alternatives were evaluated and proposed in the use of biodiesel as an alternative fuel, choosing the geometry of 5 outlets because the pressure remained constant with the use of diesel fuel and the frying oil biofuel, with all the combinations, which which indicated that a variation was necessary and not other complementary accessories on the engine. Keywords: Injectors, MEP engine, biofuel, diesel. Resumen Este trabajo mostró el uso de combustibles alternativos como medio de generación de energía usando biodiesel a base de aceite de frituras mediante una evaluación y simulación del flujo de combustible en los inyectores de un motor MEP. Con la aplicación del método experimental se realizó pruebas en el diésel normal, biodiesel con mezclas B10, B20 y B100 en los inyectores mecánicos para observar su presión de apertura, tiempo de cierre, ángulo de pulverización y el goteo de los mismos. Con los datos obtenidos de las pruebas en el laboratorio, se empleó el método estadístico para verificar si se encontraban en el rango habitual de funcionamiento de los inyectores para proceder a la simulación en software ANSYS, evaluando el comportamiento del fluido dentro del inyector, además de obtener valores de presiones y velocidades en el flujo del fluido dentro del mismo. De tal forma, se evaluó y propuso alternativas en el uso del biodiesel como combustible alternativo, escogiendo la geometría de 5 salidas debido que la presión permaneció constante con el uso del combustible diésel y el biocombustible de aceite de frituras, con todas las combinaciones, lo cual indicó que era necesario una variación y no otros accesorios complementarios en el motor. Palabras Clave: Inyectores, motor MEP, biocombustible, diésel.

In diesel engines, the electromechanical fuel control (EFC) actuator plays a vital role to regulate the fuel flow rate and pressure. It uses electrical energy to actuate the fuel valve, usually mechanical valve and control fuel pressure injected into diesel engine. The rotary and linear actuators are most common in diesel engine and selected based on space constraints and its reliability. As EFC actuator plays critical fuel controlling function in engine, the issues with EFC during engine operation could cause engine dysfunction. This paper studies the major issues observed with EFC actuators which has led to engine operation failures in genset application.

The cost of fuel and its availability are among the most major concerns for aircrafts and the aviation industry overall. Environmental difficulties with chemical pollutant emissions emitted by aviation machines are also connected to fuel consumption. As a result, it is crucial to examine factors that affect the overall fuel usage and consumption in the airport-based aviation industry. Several variables were investigated related to the total fuel consumed, such as dry operating weight (DOW) (KG), zero-fuel weight (ZFW), take-off weight (TOW), air distance (AIR DIST) (KM), and ground distance (GDN DIST). Analysis of the correlation between total fuel consumed as well as the extra fuel and selected variables was conducted. The results showed that the most positively associated factors with the total used fuel were the air distance (r2 = 0.86, p &lt, 0.01), ground distance (r2 = 0.78, p &lt, 0.01), TOW (r2 = 0.68, p &lt, 0.01), and flight time (r2 = 0.68, p &lt, 0.01). There was also a strong positive association between the average fuel flow (FF) and actual TOW (r2 = 0.74, p &lt, 0.01) as well as ZFW (r2 = 0.61, p &lt, 0.01). The generalized linear model (GLM) was utilized to assess the predictions of total energy usage after evaluating important outliers, stability of the homogeneity of variance, and the normalization of the parameter estimation. The results of multiple linear regression revealed that the most significant predictors of the total consumed fuel were the actual ZFW (p &lt, 0.01), actual TOW (p &lt, 0.01), and actual average FF (p &lt, 0.05). The results interestingly confirmed that wind speed has some consequences and effects on arrival fuel usage. The result reflects that thermal and hydrodynamic economies impact on the flying fuel economy. The research has various implications for both scholars and practitioners of aviation industry.

Portable Fuel Containers (PFCs) made for consumer use can, under unusual circumstances, develop a flammable atmosphere in the container headspace. In order to prevent an inadvertent ignition from causing flame propagation into this headspace and a subsequent explosion or flame jetting, PFC manufacturers are developing prototype Flame Mitigation Devices (FMDs) for installation in the PFC. A test method is described in this paper to determine if the installed FMD will indeed prevent flame entry into the PFC in a high-challenge flame propagation scenario. The method entails the use of a butane-air mixture ignited in a 5 cm diameter, 12 cm long tube attached to either the container neck or a spout on the container neck. Two concept FMD designs have successfully prevented repeated attempts at flame propagation into the PFC and have also produced encouraging results in tests for fuel flow restriction, duel dispensing nozzle friction, and prolonged fuel exposure. Versions of these tests are currently being promulgated in a draft ASTM standard on PFC FMDs.

Solid oxide fuel cell (SOFC) plant is considered a most important type in the field of fuel cells, which gives control difficulties such as fuel flow constraints, load disturbance, system nonlinearities, and parameter uncertainties. However, due to these difficulties, the voltage control of SOFC plant is extremely difficult. In this paper, a new intelligent proportional integral-adaptive sliding mode control (iPI-ASMC) with anti-windup compensator is proposed to control the output voltage of SOFC plant to keep up with the rated voltage. The referred iPI-ASMC is made of three sub-components: (i) an extended state observer (ESO)-based-intelligent proportional-integral to estimate the unknown dynamic, (ii) an adaptive sliding mode control is added to compensate the estimation error of unknown dynamic, and (iii) an anti-windup compensator based on back-calculation is used to deal with saturation problem which is caused by input constraints. Moreover, the effectiveness and efficiency of the proposed iPI-ASMC strategy is demonstrated by comparing with some other approaches such as conventional proportional integral-derivative (PID) controller, intelligent proportional-integral (iPI) and fuzzy PID controller. Corresponding simulation results show that the proposed iPI-ASMC approach provides better dynamic responses and outperforms to compared methods in term of settling time, peak overshoots, integral absolute error (IAE), integral square error (ISE), and integral time absolute error (ITAE).

The focus of this paper is on small low-cost turbojet engines equipped with a gear-type fuel pump rather than a more traditional fuel metering unit. The incorporation of such type of fuel flow actuation devices introduce additional nonlinearities into the system and therefore make traditional modeling and system identification methods difficult to apply. In this paper, we propose a nonlinear fast engine model structure that can be used for various applications, including identification, modeling and simulation, and controller design of such sub-class turbojet engines. A high-fidelity turbojet engine model including its nonlinear gear-type fuel pump is developed, which is later used to generate the fast engine model. The parameters of the fast engine model are estimated using regression analysis. The identification procedure is also applied to real engine test data to verify the proposed approach.

The paper presents a numerical study (Eulerian multiphase approach) on the influence of physical characteristics of different fuels (density and dynamic viscosity) on the fuel flow pattern at the injection nozzle exit considering different fuels and operating parameters of a diesel engine (fuel temperature and compression ratio). A new term, Nozzle Uniformity Coefficient (NUC) was introduced to define the fluid flow pattern at the injection nozzle exit and to correlate its value with a further development of the spray in the combustion chamber. The results of the analysis show that the structure of the fluid flow pattern is the most homogeneous in the case of low fuel temperatures and low back pressures. Fuel velocities have an immediate effect on the spray development, the air-fuel mixing process, and the depth of jet penetration into the combustion chamber. The average values of biodiesel fuel velocities are lower compared to those of diesel fuel. In view of the increasing use of fuels from renewable sources (biofuels), a logical conclusion is that it is necessary to correlate the injection system components with their physicochemical properties.

The pyrolysis reactions within a self-made jet pyrolysis reactor were simulated using FLUENT software. The effects of process parameters and reactor structural parameters on the pyrolysis reaction efficiency were studied. Within certain ranges, the CeO2 yield can be improved by reducing the inlet fuel flow rate or by increasing the CeCl3 concentration. To ensure two-phase mixing homogeneity and reaction efficiency inside the reactor, the optimized value of the diameter ratio of the drainage pipe to the throat mouth is 10/5, the angle between the drainage pipe and the throat mouth is 90°, and the drainage pipe diameter is 10 mm.

Deposits, which form within various parts of internal combustion engines, can affect normal engine operation and result in diverse negative effects. Versatile research over the last decades revealed that the formation and reduction of deposits is the result of a complex interaction between the physical boundary conditions at the place of interest and of the fuel properties. To appropriately catch this complexity, an abstract, generalized kinetic model for deposit formation and reduction mechanisms is developed within this publication. It accounts both for the chemical and physical properties of the fuel mixture on a single component basis and for the physical boundary conditions at the site of interest. Due to an included explicit time dependence, it is also able to describe the effect of boundary condition changes and hence dynamic engine operation. In the second part of this publication the model is applied to the concrete case of internal deposit formation of a GDI injector during continuous engine operation, where the fuel flow drift caused thereby is used as the measure for the deposit amount. The deposit formation tendencies within the engine map, i.e. various engine speed and load points, are investigated and the results are interpreted by evaluating the impact of the operation point changes on the deposit kinetics. In a last step, selected desposit formation and reduction phenomenons during engine operation are discussed, which show the necessity for a model with a component basis of both fuel and deposit composition.

In this study, the effects of the flight-path angle (FPA) ranging between 1.0 and 4.5 deg during a continuous descent approach, on certain fuel-related parameters such as fuel flow, fuel burn per 1000 ft of altitude, and specific range, are investigated. The dataset, obtained from Turkish Airlines, includes 4384 eligible flight data records of narrow-bodied commercial aircraft performing 9351 domestic flights between 30 city pairs, across Turkey. The results indicate that the fuel flow is a strong linear function of FPA up to 2.5-3.0 deg for all of the aircraft types, whereas the effect diminishes above 3.0 deg. There is a monotonic decrease of the fuel burn per 1000 ft of altitude with an increase in the FPA, with the trend being stronger than that for fuel flow. Even though the fuel consumption of the descent flight significantly decreases with steeper FPAs, the effect of the FPA on the total fuel consumption of the flight seems not as straightforward as it does when considering only the descent phase. A case study based on this model indicates a U-shaped pattern for total fuel burn with an increase in the FPA, in which the highest fuel saving relative to 1.0 deg of the FPA is calculated to be 14.0% (191 kg) at 2.5 deg of the FPA.

This paper aimed to evaluate the effects of air and fuel supercharge in an agricultural engine. Variables analyzed were torque, power and specific fuel consumption. Dynamometric experiments were carried out by means of the power take-off of an agricultural tractor. The experiment was conducted in a laboratory, with a completely randomized design in a bi-factorial arrangement, with three repetitions, six engine configurations being evaluated (Natural aspiration; Natural aspiration + Service; Turbocharged; Turbocharged + Service; Turbocharged + Intercooler; Turbocharged + Service + Intercooler) and 10 engine speeds (1,200; 1,300; 1,400; 1,500; 1,600; 1,700; 1,800; 1,900; 2,000 e 2,100 rpm). Results indicated that only the addition of the turbocharger does not increase the torque and power of the engine. The increase in fuel flow increases engine performance for any of the evaluated configurations. Turbocharged + Service and Turbocharged + Service + Intercooler configurations reduced specific fuel consumption by up to 10% and increased torque and power by approximately 30%, in relation to the original configuration (Natural aspiration). This paper aimed to evaluate the effects of air and fuel supercharging in an agricultural engine. The analyzed variables consisted of torque, power, and specific fuel consumption. Tests were carried out using a dynamometer through the power take-off of an agricultural tractor. The experiment was carried out at a laboratory in a completely randomized design arranged under a two-factorial scheme, with three replications. Six engine configurations (natural aspiration, natural aspiration + service, turbocharger, turbocharger + service, turbocharger + intercooler, and turbocharger + service + intercooler) and 10 engine speeds (1,200, 1,300, 1,400, 1,500, 1,600, 1,700, 1,800, 1,900, 2,000, and 2,100 rpm) were evaluated. The turbocharger alone did not increase engine torque and power. The increase in fuel flow enhanced engine performance for the evaluated configurations. Turbocharger + service and turbocharger + service + intercooler configurations reduced specific fuel consumption by up to 10% and increased torque and power by approximately 30% compared to the original configuration (natural aspiration).

In this paper, the publicly available dataset for the Combined Diesel-Electric and Gas (CODLAG) propulsion system was used to obtain symbolic expressions for estimation of fuel flow, ship speed, starboard propeller torque, port propeller torque, and total propeller torque using genetic programming (GP) algorithm. The dataset consists of 11,934 samples that were divided into training and testing portions in an 80:20 ratio. The training portion of the dataset which consisted of 9548 samples was used to train the GP algorithm to obtain symbolic expressions for estimation of fuel flow, ship speed, starboard propeller, port propeller, and total propeller torque, respectively. After the symbolic expressions were obtained the testing portion of the dataset which consisted of 2386 samples was used to measure estimation performance in terms of coefficient of correlation (R2) and Mean Absolute Error (MAE) metric, respectively. Based on the estimation performance in each case three best symbolic expressions were selected with and without decay state coefficients. From the conducted investigation, the highest R2 and lowest MAE values were achieved with symbolic expressions for the estimation of fuel flow, ship speed, starboard propeller torque, port propeller torque, and total propeller torque without decay state coefficients while symbolic expressions with decay state coefficients have slightly lower estimation performance.

In this paper we propose a mathematical model for the fuel consumption analysis during aircraft cruise. A closed-form formula that expresses the aircraft’s weight variation over time, and hence, the fuel flow rate, is obtained as a result. Furthermore, a closed-form expression of the aircraft’s main performance parameters is also obtained. We compare the values of such parameters computed by using the Piano-X software and computed by using our mathematical model. Simulation results confirm that our mathematical model provides results very close to reality. Finally, the closed-form formula of the fuel flow rate provided by our model is used to improve the calculation of the carbon dioxide emissions for four example routes, which, unlike here, are usually obtained under the assumption of a constant value of the fuel flow rate.

A billets reheating furnace simulator was used to identify the variables that must be measured with more accurate devices and methods to estimate the furnace's energy efficiency when real energy audits are performed. For this purpose, experiments were statistically designed, and easy-to-implement data analysis methods were employed. The results analysis shows that the variables with practical and statistically significant effect on energy efficiency are the percentage of O2 in the combustion gases, the fuel flow in the burners, and the combustion air temperature. A confirmatory experiment validated the results analysis and points out that Design of Experiments is a tool that cannot be ignored by those who perform energy audits or have the responsibility to combat energy waste in energy-intensive manufacturing industries.

A billets reheating furnace simulator was used to identify the variables that must be measured with more accurate devices and methods to estimate the furnace's energy efficiency when real energy audits are performed. For this purpose, experiments were statistically designed, and easy-to-implement data analysis methods were employed. The results analysis shows that the variables with practical and statistically significant effect on energy efficiency are the percentage of O 2 in the combustion gases, the fuel flow in the burners, and the combustion air temperature. A confirmatory experiment validated the results analysis and points out that Design of Experiments is a tool that cannot be ignored by those who perform energy audits or have the responsibility to combat energy waste in energy-intensive manufacturing industries.

In this experimental case, a vessel G/T was run with marine fuel (MF)/aspires oil methyl ester (AME) mixtures. The blends tested were marine fuel (MF), 50 % of aspire oil methyl ester, 100 % of aspire oil methyl ester (AME), and 100 % of MF by volume. The G/T was operated at 4 loads, 20 %, 60 %, 80 % and 100 %. Turbine power generation and emissions performance were tested. The results that AME content in the fuel mixture increased, the fuel flow rate increased to maintain the constant speed operation and equivalence ratio reduced. The results of tested that turbine can operate with AME blends in MF without any modification. Exhaust gas temperatures reduced with increasing AME content. Higher AME blends resulted in lower CO2, CO emissions while NOx emissions increasing. Finally, various energetic performance parameters of the engine were evaluated and compared with each other. This study shows that a turbine engine can be operated successfully with marine fuel (MF) and aspire oil methyl ester (AME) mixtures.

This study aims to visualize the non-premixed flames in a radial flow burner equipped with swirl vanes and to analyze the stability of flames. The study was carried out using concentric pipes, an air pipe 2 inch in diameter and a fuel pipe 6 mm in diameter. Fuel was injected through 3 holes with diameter of 1.5 mm. The fuel used is LPG and the air is supplied from a blower with a speed range of 3.8-6.6 m/s. The air passed a swirl vane with angles O=10°, 30°, 50°. The stability limits of the flame at fixed air velocities were obtained by increasing the fuel velocity until the flame blowed out. The fuel velocity were then plotted into a flame stability diagram. Furthermore, structures of the flame were visualized from ignition until the flame blows out using video camera with 240 fps. The results show that in general larger angle of the swirl vane increases levels of flame stability. At relatively low air speeds, the swirl with O=50° shows the broadest stability limits compared to O=10° and 30°. While at higher air velocity the stable flame area of the swirl with O=50° is narrower compared to O=30°. At the blade angle O=10° and O=30 ° increase in air velocity causes an expansion in flame stability, whereas at O=50° increase in air velocity causes a decrease in flame stability.

On-wing washing for civil aviation engine is an important approach to improve the Exhaust Gas Temperature Margin (EGTM), and to reduce the fuel consumption as well as the resultant aviation emission. In view of the fuel flow reduction achieved by on-wing washing, this study proposes an estimation method of engine performance improvement due to washing according to fleet fuel consumption savings and engine washing costs. Finally, the engine washing interval of a fleet can be optimized based on the proposed performance assessment method of on-wing washing. A case study of one airline fleet of 200 CFM56 Engines demonstrates the effectiveness of the proposed method. The results show that the optimal washing interval is 3 times a year, and that an average annual cost savings of 20.15 million dollars can be achieved by reducing 5471 ton fuel consumption and 17,250 ton CO 2 emission.

En Honduras en el 2106 se presentó un problema de aprovechamiento de madera de pino afectada por el Dendroctunus Frontalis, el cual afectó a 389.024.38 ha de pino. Por tal motivo es necesario una solución viable a dicho problema, por lo cual se propone el estudio de ubicación de dos escenarios para el manejo de la biomasa. En el Escenario 1 se desea instalar una planta con capacidad de 50MW y para el Escenario 2 se instala zonificado dos plantas de potencia una de 35 MW y otra de 25 MW para verificar, cuál de las dos soluciones genera un costo unitario de Kilowatio-hora más bajo. En este caso, se evaluaron cuatro tipos de tecnologías de plantas de potencia para recudir al máximo el flujo de combustible en cada escenario. En este caso el Escenario 2 nos presenta los mejores valores de costo unitarios de kilowatio-hora siendo estos en la planta de potencia CR3REG2REC para la número 1 con capacidad de 35 MW netos y en la planta de potencia CR3REG2REC número 2 con capacidad de 25 MW netos en US$ 0.0543/kWh y 0.0799 US$/kWH respectivamente.

The Fuel_LF-RTO strategy is real-time optimization (RTO) strategy proposed here to find the optimal values of fueling for the polymer electrolyte membrane fuel cell hybrid power sources under unknown load profile, which is the case of fuel cell vehicle. The proposed optimization strategy is based on global extremum seeking (GES) algorithm and load-following (LF) control for air and fuel flows. The results show the performance obtained with Fuel_LF-RTO strategy in comparison with the Static Feed-Forward strategy. The performance was estimated for constant and variable load. The FC system efficiency and the fuel consumption efficiency for maximum load of 8 kW can increase with up to 1.88% and 11.26 W lpm(-1) in comparison with the sFF RTO strategy. Also, the fuel economy is 27.36 L during the 8 kW/12 s constant load cycle, which means an economy of 136.8 lpm. This performance is highlighted for constant load in range 2 to 8 kW, which represents 0.33% and 1.25% from nominal power of the 6 kW FC stack used in this study. Also, the performance was estimate for variable load considering the fuel economy, which can be up to 21.86 l during the 6.25 kW/12 s pulsed load cycle.

This paper describes the development of an optimization-based cooperative planning system for the efficient routing and scheduling of extended flight formations. This study considers the use of formation flight as a means to reduce the overall fuel consumption in long-haul airline operations. It elaborates on the operational implementation of formation flight, particularly focusing on the formation flight routing. A completely decentralized approach is presented, in the sense that formation flight is not planned pre-flight and is not subjected to any predefined routing restrictions. A greedy communication scheme is defined through which all participating aircraft are allowed to communicate with neighboring aircraft in order to establish flight formations in flight. A constraint on the formation-flight-induced additional flight time is introduced in order to suppress the occurrence of large detours in the assembly of flight formations. A transatlantic case study is presented that considers 347 eastbound flights. Assuming a 10% fuel flow reduction for any trailing aircraft in a formation, the overall network-wide fuel savings were estimated at 4.3% at the expense of an additional flight time of 10.3 min per flight on average. In this transatlantic long-haul scenario, a formation flight usage rate of 73% was realized.

Internal deposit formation in the injector nozzle can both restrict the fuel flow and alter the spray characteristics of the injectors, which will lead to a loss in power and fuel economy, as well ...

Studies have shown that using higher operational capacity harvesters render less fuel consumption per harvested area and, as a result, less operating expenses. This paper aims to obtain the effective fuel consumption per hour of the CASE IH A4000 harvester during the mechanical harvest of raw sugar cane. The study took place in a sugar cane plantation with mechanical harvest in an area belonging to a producer for Coagro (Cooperativa Agroindustrial do Estado do Rio de Janeiro Ltda.) (Agroindustrial Cooperative of the State of Rio de Janeiro), in the municipality of Campos dos Goytacazes, Rio de Janeiro/Brazil. The variety of sugar cane was evaluated at RB867515 in its third cut. The system of automatic data acquisition was built from a volumetric flow sensor to determine the fuel flow, in addition to a data collector (Datalogger) and a global positioning system (GPS) device. To determine the fuel consumption per hour, data from the fuel flow sensor were used. The consumption per hour of fuel was 33.9 L.h-1. The effective consumption was estimated in 1.84 L. ton-1. The consumption per hour and the effective consumption of the CASE IH A4000 were more than double of what the manufacturers stipulated, which means, the consumption is much higher than desirable. Los trabajos realizados han demostrado que la utilización de cosechadoras de mayores capacidades operativas ha proporcionado menores consumos de combustibles por área cosechada y, consecuentemente menores costos operacionales. Este trabajo tuvo como objetivo la obtención del consumo horario y efectivo de combustible de la cosechadora CASE IH A4000 durante operación de cosecha mecanizada de caña cruda. El estudio fue realizado en una planta de caña de azúcar sistematizada para la cosecha mecanizada en área perteneciente a un cooperado de Coagro (Cooperativa Agroindustrial do Estado do Rio de Janeiro Ltda.) en el municipio de Campos dos Goytacazes, Brasil. La variedad de caña de azúcar evaluada fue la RB867515 en su tercer corte. El sistema de adquisición automática de datos está constituido por un sensor de flujo volumétrico para determinar el flujo de combustible, además de un colector de datos (Datalogger) y un sistema de posicionamiento global (GPS). Para determinar el consumo horario de combustible, se utilizaron los datos obtenidos por el sensor de flujo de combustible. El consumo de horas de combustible fue 33,9 L.h-1. El consumo efectivo se estima en 1,84 L. ton-1. El consumo horario de combustible y el consumo efectivo de la cosechadora CASE IH A4000 fueron mayores que el doble de lo estipulado por los fabricantes de la máquina, significando que el consumo está mucho más allá de lo deseable. Trabalhos realizados têm mostrado que a utilização de colhedoras de maiores capacidades operacionais tem proporcionado menores consumos de combustíveis por área colhida e, consequentemente, menores custos operacionais. Este trabalho teve como objetivo a obtenção do consumo horário e efetivo de combustível da colhedora CASE IH A4000 durante operação de colheita mecanizada de cana crua. O estudo foi realizado em uma lavoura de cana-de-açúcar sistematizada para a colheita mecanizada em área pertencente a um cooperado da Coagro (Cooperativa Agroindustrial do Estado do Rio de Janeiro Ltda.) no município de Campos dos Goytacazes/RJ. A variedade de cana-de-açúcar avaliada foi a RB867515 em seu terceiro corte. O sistema de aquisição automática de dados foi constituído de um sensor de fluxo volumétrico para determinação do fluxo de combustível, além de um coletor de dados (Datalogger) e de um sistema de posicionamento global (GPS). Para determinar o consumo horário de combustível, foram utilizados os dados obtidos pelo sensor de fluxo de combustível. O consumo horário de combustível foi 33,9 L.h-1. O consumo efetivo foi estimado em 1,84 L. ton-1. O consumo horário de combustível e o consumo efetivo da colhedora CASE IH A4000 foram maiores que o dobro do estipulado pelos fabricantes da máquina, significando que o consumo está muito além do desejável.

The fuel flow in the working chamber of the common rail fuel injector, which is a submerged jet flow, determines the needle movement and causes great effects on the fuel injection performance. This work presents an experimental investigation on the submerged jet flow characteristics of a cylindrical orifice under conditions of varied boundary pressures. A full-scale optical test rig is set up to examine the submerged flow of the cylindrical orifice based on a fuel pump test bench. The optical experimental results reveal that the inner cylindrical orifice flow induces cavitation and causes influences on the submerged jet flow. As the inner cavitation is at the cylindrical orifice outlet, the cylindrical orifice discharge coefficient declines but the mass flow rate becomes choking. The test results also show the boundary pressures (the inlet and outlet pressures) of the cylindrical orifice have great influences on the impingement force of the submerged jet flow. The development process of the impingement force is divided into two periods: the stable period and the fluctuation period. Moreover, the impingement force increases quadratically with the increase in the mass flow rate. Once the choking flow happens, it is useless to increase the jet impingement force by improving the inlet pressure.

This paper focuses on the development of a real-time furnace-balancing scheme for a reformer at a centralized hydrogen facility using steam methane reforming (SMR) technology so that the reformer fuel input can be optimized in real-time to increase the plant throughput and to reject operational disturbances associated with flow control valves. Initially, the framework for the furnace-balancing scheme, the statistical-based model identification and the valve-to-flow-rate converter developed in Tran et al., 2017a , Tran et al., 2018 are integrated with a heuristic search algorithm to create a real-time balancing procedure, which recursively calculates different total fuel flow rates of which the respective spatial distribution to burners is optimized until key operational specifications, e.g., the reformer throughput is maximized, and the outer tube wall temperature (OTWT) along the reforming tube length of all reforming tubes must not exceed the design temperature of the reforming tube wall, are satisfied. Subsequently, a com;1;putational fluid dynamic (CFD) model of the reformer developed in Tran et al. (2017b) is used to represent the on-line unit at the SMR-based hydrogen facility and is used to characterize the previously unstudied dynamic behavior of the reformer, based on which we develop an optimal strategy to implement the optimized total fuel flow rate to maximize the reformer throughput. Finally, a case study in which the balancing procedure is implemented on the reformer initially operated under the nominal reformer input is proposed, and the results are used to demonstrate that the furnace-balancing scheme successfully determines the optimized reformer fuel input to increase the reformer throughput while meeting the OTWT limits.

The paper deals with the issue of determining the geometry of fuel spray generated by the outward-opening type of injectors. The design of the outward-opening type injector is the reason for the initial fuel flow taking a circular shape (an empty cone). With increasing pressure of the injected fuel this geometry changes into a square one. The aim of the research was to determine the conditions of these changes and to propose how to define the geometry in the form of an indicator z (accepting positive values – for circular geometry, and negative values – for square geometry) as well as to generalize the equation zeq making it possible to determine the indicator of the fuel spray geometric structure changes. The defined indicator z shows that fuel injection pressure exceeding 15 MPa plays an important role in changing the geometric structure of the fuel spray. The back pressure of the medium into which the fuel is injected does not affect the determined value of the indicator. Additionally, an indicator of variation of radial penetration of the fuel spray CoV(Sr) and the indicator of linear to radial fuel spray penetration Sl/Sr-av were determined, which only under certain conditions can replace the z indicator.

WOS: 000429187500024, PubMed ID: 29414344, In this study, the effects of descent flight path angle (between 1.25 degrees and 4.25 degrees) on aircraft gaseous emissions (carbon monoxide, total hydrocarbons and nitrogen oxides) are explored using actual flight data from aircraft flight data recording system and emissions indices from the International Civil Aviation Organization. All emissions parameters are corrected to flight conditions using Boeing Fuel Flow Method2, where the ambient air pressure, temperature and humidity data are obtained from long-term radiosonde data measured close to the arrival airport. The main findings highlight that the higher the flight path angle, the higher the emission indices of CO and HC, whereas the lower the emissions index of NOx and fuel consumption. Furthermore, during a descent, a heavier aircraft tends to emit less CO and HC, and more NOx. For a five-tonne aircraft mass increase, the average change in emissions indices are found to be -4.1% and -5.7% (CO), -5.4% and -8.2% (HC), and +1.1% and +1.6% (NOx) for high and low flight path angle groups, respectively. The average emissions indices for CO, HC and NOx during descent are calculated to be 24.5, 1.7 and 5.6 g/kg of fuel, whereas the average emissions for descending from 32,000 ft (9.7 km) and 24,000 ft (7.3 km) are calculated to be 7-8 kg (CO), similar to 0.5 kg (HC) and similar to 3 kg (NOx)

Combined cycle gas turbine (CCGT) power plants must often run at part-load conditions, as the electricity demand varies constantly. We present a method and necessary correlations for simulating the part-load operation of a typical CCGT plant in a commercial simulator (e.g. GateCycle). We show that assuming constant values for some equipment parameters (e.g. efficiencies) and ignoring the operating maps of key equipment can overestimate plant performance significantly at part-loads. Furthermore, a rise in the ambient temperature lowers the plant capacity, but increases the plant efficiency. Then, we propose a simulation-based optimization approach that yields an optimal operating strategy to maximize the overall plant efficiency for any part-load. Our strategy forms a basis for evaluating the two widely used operating policies (fuel flow control or FFC and inlet guide vane control or IGVC). Our proposed strategy increases the plant efficiency by as much as 2.63% (absolute) over FFC and 0.93% over IGVC. This work highlights the need for integrating the two cycles (gas turbine and steam) to optimize the plant performance. We find that FFC seems to prioritize the gas turbine and IGVC tends to prioritize the steam cycle, while our proposed strategy strikes an optimal balance between the two.

The ASEAN's legislation has become more regulatory towards electric vehicles for automotive manufacturers to ensure the environment is preserved better for future generations. The ASEAN roadmap 2025 requirement in optimizing a conventional vehicle's fuel consumption is implemented with hybrid technology in targeting the automotive industry worldwide to achieve energy-efficient vehicles. This research aims to develop a vehicle model via 1D simulation cycle and implement the 48V mild hybrid to lower vehicle fuel consumption considering perspective in drive cycles data. The vehicle model used in this research is a D-segment vehicle powered by a 1.8L TGDI engine. The base model will be created using a GT Suite software where data is compared and analyzed with actual vehicle measurement. There will be two models produced; with and without Belt-Alternator-Starter (BAS) system. They will be further investigated for their functions based on NEDC and RDC drive cycles for fuel consumption. However, implementing the add-on technology from this simulation improved overall vehicle fuel consumption by 7.7% in NEDC and 1.7% in RDC. The results obtained for the optimization of the vehicle have shown difference by the results of each engine characteristics such as engine fuel flow rate, speed, torque, the BAS functions, and state of charge. The research proposes its findings to understand the practical usage of 48V mild hybrid system in fuel reduction and provide reliable proof to use as a reference for initiative studies.

This paper discloses a new algorithm, called sustainable supersonic fuel flow method, to complement the conceptual design of future supersonic aircraft with pollutant and greenhouse gases emissions estimation. Starting from already existing algorithms currently used to assess the environmental impact of already developed and operating aircraft, the authors suggest revisions to improve the formulations, thus extending their application. Specifically, this paper has two objectives: to support the design of future supersonic aircraft and to evaluate the impact of the exploitation of more sustainable aviation fuels, with special focus on biofuels and biofuel blends, since the conceptual design stage. The core of the algorithm developed to predict in-flight emissions of a supersonic aircraft has been validated with public data of Concorde flight experiments. In addition, corrective factors accounting for the most recently developed and certified biofuels have been included in the formulation.