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In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.

The study aims to determine the the optimal value of output parameters of a variable compression ratio (CR) diesel engine are investigated at different loads, CR and fuel modes of operation experimentally. The output parameters of a variable compression ratio (CR) diesel engine are investigated at different loads, CR and fuel modes of operation experimentally. The performance parameters like brake thermal efficiency (BTE) and brake specific energy consumption (BSEC), whereas CO emission, HC emission, CO₂ emission, NO_x emission, exhaust gas temperature (EGT) and opacity are the emission parameters measured during the test. Tests are conducted for 2, 6 and 10 kg of load, 16.5 and 17.5 of CR.

In this investigation, the first engine was fueled with 100% diesel and 100% Calophyllum inophyllum oil in single-fuel mode. Then Calophyllum inophyllum oil with producer gas was fed to the engine. Calophyllum inophyllum oil offers lower BTE, CO and HC emissions, opacity and higher EGT, BSEC, CO₂ emission and NO_x emissions compared to diesel fuel in both fuel modes of operation observed. The performance optimization using the Taguchi approach is carried out to determine the optimal input parameters for maximum performance and minimum emissions for the test engine. The optimized value of the input parameters is then fed into the prediction techniques, such as the artificial neural network (ANN).

From multiple response optimization, the minimum emissions of 0.58% of CO, 42% of HC, 191 ppm NO_x and maximum BTE of 21.56% for 16.5 CR, 10 kg load and dual fuel mode of operation are determined. Based on generated errors, the ANN is also ranked for precision. The proposed ANN model provides better prediction with minimum experimental data sets. The values of the R² correlation coefficient are 1, 0.95552, 0.94367 and 0.97789 for training, validation, testing and all, respectively. The said biodiesel may be used as a substitute for conventional diesel fuel.

The blend of Calophyllum inophyllum oil-producer gas is used to run the diesel engine. Performance and emission analysis has been carried out, compared, optimized and validated.

This study aims to investigate the aviation, energetic, exergetic, environmental, sustainability and exergoeconomic performances of a micro turbojet engine used in unmanned aerial vehicles at four different modes.

The engine data were collected from engine test cell. The engine performance calculations were performed for four different operation modes.

According to the results, maximum energy and exergy efficiency were acquired as 19.19% and 18.079% at Mode 4. Total cost rate was calculated as 6.757 $/h at Mode-1, which varied to 10.131 $/h at Mode-4. Exergy cost of engine power was observed as 0.249 $/MJ at Mode-1, which decreased to 0.088 $/MJ at Mode-4 after a careful exergoeconomic analysis.

The novelty of this work is the capability to serve as a guide for similar systems with a detailed approach in the thermodynamic, thermoeconomic and environmental assessments by prioritizing efficiency, fuel consumption and cost formation. This investigation intends to establish a design of the opportunities and benefits that the thermodynamic approach provides to turbojet engine systems.

The distribution sector has been hard hit by the energy/ecology crisis. Higher fuel costs coupled with reduced availability of many energy sources have adversely affected distribution activities. Growing levels of pollution have caused global concern. As a part of the physical distribution activity, the transportation modes have been particularly vulnerable to the energy/ecology crisis because they rely so heavily on energy resources. It is important that those involved in physical distribution understand the distribution‐energy/ecology interface. Recognition of the effects that the energy/ecology crisis has had, and will have, on distribution is an integral part of logistics planning and control. The energy/ecology crisis will not go away and it behoves the physical distribution manager, educator and public policy maker to: (1) Understand the Problem, (2) Recognise how the problem pertains to him directly and/or indirectly, and (3) Determine how he and others will react to the problem in the future.

This paper addressed some critical issues in the development of hybrid electric powertrains for aircraft and propose a design methodology based on multi-objective optimization algorithms and mission-based simulations.

Scalable models were used for the main components of the powertrain, namely, the (two stroke diesel) engine, the (lithium) batteries and the (permanent magnet) motor. The optimization was performed with the NSGA-II genetic algorithm coupled with an in-house MATLAB tool. The input parameters were the size of engine, the hybridization degree and the specification of the battery (typology, nominal capacity, bus voltage, etc.). The outputs were electric endurance, additional volume, performance parameters and fuel consumption over a specified mission.

Electric endurance was below 30 min in the two test cases (unmanned aerial vehicles [UAVs]) but, thanks to the recharging of the batteries on-board, the total electric time was higher. Fuel consumption was very high for the largest UAV, while an improvement of 11 per cent with respect to a conventional configuration was obtained for the smallest one.

The research used a simplified approach for flight mechanics. Some components were not sized in the proposed test cases.

The results of the test cases stressed the importance of improving energy density and power density of the electric path.

The proposed methodology is aimed at minimizing the environmental impact of aircraft.

The proposed methodology was obtained from the automotive field with several original contributions to account for the aircraft application.

More stringent emission standards are being promulgated all over the world for regulating and decreasing the levels of emission more so caused from on-road vehicles and engines and for improving the air quality problems.

In this study, an attempt has been made to experimentally analyze the performance and emission characteristics of the premixed charge compression ignition (PCCI) mode assisted by a pilot injector.

The results indicate that brake thermal efficiency marginally decreases, and specific fuel consumption increases in all PCCI modes, and HC, CO emissions are higher in the case PCCI modes and oxides of nitrogen and soot levels are considerably reduced in the case of diesel PCCI-biodiesel and petrol PCCI-biodiesel modes.

As obtaining very lean homogenous mixture is hard, it becomes difficult to sustain PCCI mode over the operating range of varying speeds and loads to effectively control the PCCI combustion over the operating range.

Being a responsible human being, we all have the responsibility in keeping this world cleaner, free from all sort of pollution. In this regard, the concept of waste recycling and energy recovery plays a vital role in the development of any economy. This has led to resource conservation and pollution reduction.

The present work Jatropha oil methyl ester (JOME) was chosen as fuels for PCCI mode. Investigations were carried out with blends of JOME with diesel in PCCI combustion mode to evaluate the performance, combustion and emission characteristics of these fuels.

TO deliver a lecture in commemoration of the Wright Brothers before the Institute of Aeronautical Sciences is a great honour of which I am deeply aware: this honour one feels is due not solely to the technical situation but to somemore subtle link between the Institute and the Royal Aeronautical Society and our two countries.

Over past decades, the fossil fuel reserves in the world have been decreasing at an alarming rate and a lack of crude oil is expected in the early decades of this century. Also, the eco-neutral pollutants such as carbon monoxide (CO), oxides of nitrigen (NOx) and unburnt hydrocarbons (UHC) are also increasing. This calls for innovative research in non-conventional fuels to replace fossil fuels. Hydrogen is one such fuel which has an exceptional combustion property and appears to be proving itself as the best transportation fuel of the future. On the other hand, compressed natural gas(CNG) has already been credited as a remarkable fuel for its better emission characteristics and has been implemented as a transportation fuel in metros. Therefore, the use of hydrogen blended with natural gas seems to be a viable alternative to pure fossil fuels because of the expected reduction of the total pollutants and increase of efficiency. This paper aims to investigate this issue.

In the present experimental investigation, 10 and 20 per cent of hydrogen–CNG mixture(HCNG) by mass of fuel is inducted into the combustion chamber in conjunction with air in HCNG–diesel dual fuel mode. The variation in injection opening pressure is assessed to optimize the performance and emission characteristics.

Experiments were conducted at three different injection opening pressures, i.e. 200, 220 and 240 bar, at full-load condition and the performance characteristics were calculated. The effect of injection operating pressure(IOP) on emissions were measured and compared with pure diesel mode.

Brake thermal efficiency (BTE) was increased by 1.2 per cent at 220 bar. Minimum BSFC of 0.2302 kg/kWh, 0.2114 kg/kWh was noticed for 220 bar with a changing ratio of 20 per cent of HCNG. It was noticed that CO and UHC decreased with variation in IOP and HCNG content in the blend. However, there was an increase in NOx emissions.