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Microscopic traffic simulators that simulate realistic traffic flow are crucial in studying, understanding and evaluating the fuel usage and mobility effects of having a higher number of autonomous vehicles (AVs) in traffic under realistic mixed traffic conditions including both autonomous and non-autonomous vehicles. In this paper, L4-L5 AVs with varying penetration rates in total traffic flow were simulated using the microscopic traffic simulator Vissim on urban, mixed and freeway roadways. The roadways used in these simulations were replicas of real roadways in and around Columbus, Ohio, including an AV shuttle routes in operation. The road-specific information regarding each roadway, such as the number of traffic lights and positions, number of STOP signs and positions, and speed limits, were gathered using OpenStreetMap with SUMO. In simulating L4-L5 AVs, the All-Knowing CoEXist AV and a vehicle with Wiedemann 74 driver were taken to represent AV and non-AV driving, respectively. Then, the driving behaviors, such as headway time and car following, desired acceleration and deceleration profiles of AV, and non-AV car following and lane change models were modified. The effect of having varying penetration rates of L4-L5 AVs were then evaluated using criteria such as average fuel consumption, existence of queues and their average/maximum length, total number of vehicles in the simulation, average delay experience by all vehicles, total number of stops experienced by all vehicles, and total emission of CO, NOx and volatile organic compounds (VOC) from the vehicles in the simulation. The results show that while increasing penetration rates of L4-L5 AVs generally improve overall fuel efficiency and mobility of the traffic network, there were also cases when the opposite trend was observed.

The increasing demands in modern combustion engines for low emissions and low fuel consumption improved methods for the cycle of combustion. The Beare Heads is a recent 6-hour version of the Beare Heads, recognized also as Malcolm Beare model. Beare Heads uses pistons and harbours such as a 2-hour motor and replacements for the overlap valve system of 4-hour motors. The four-stroke engine, block as well as shaft remain intact. The six-time engine was a mix of two-hit and four-hit technologies. Six Stroke is a six-stroke engine that uses two energy strokes. The six-time engine including external combustion as well as internal dual stream is the same as the real interior combustion engine, according to its mechanical design. Air heating system as well as a combustion chambers, each separate of the cylinder, are two extra chambers throughout the thermodynamic cycles. The six-stroke is heat efficient, since the power pulse pressure changes are larger than for the injection process as well as compression strokes. The major benefits of six-stroke engines included lowering fuel consumption by 40 percent, reducing emissions, versatility for multi-fuel service by 2 power strokes over the six-stroke cycles.

In the scope of the rapid technological advancements, nanoparticles (NPs) have gained prominence due to their excellent and tunable biological, and physicochemical properties. Nowadays, different methods are used for their synthesis. In particular, the green synthesis of metal precursors for the synthesis of NPs, represents a cost-effective, environmentally friendly, and hazardous chemical-free method for developing a large variety of NPs. By exploiting plant extracts, the production rate of NPs is relatively faster. Due to fossil reserves and high fuel consumption, renewable and clean energy materials are urgently needed to improve environmental sustainability. With outstanding electrochemical and physicochemical characteristics, molybdenum-based NPs (Mo-NPs) are gaining increasing attention in the fields of energy conversion and storage. Considering the significance of Mo-NPs synthesized from greener routes and their energy applications, it is necessary to review recent trends and developments in this field. This review summarizes important research studies and future research guidelines for the preparation of Mo-NPs through green routes and their applications to meet global energy and environmental demands. Moreover, future research directions are also highlighted to achieve sustainable greener precursors and Mo-NPs based energy storage devices.

We examine how behavioral adjustments by regulated vessels affect welfare outcomes of a local fuel sulfur standard targeting particulate matter pollution from maritime transport. Our analysis combines one-minute scale data of vessel locations with location-specific marginal damages to obtain voyage-level measures of welfare outcomes. Exploiting the introduction of California's Ocean-Going Vessel Fuel Rule, we find sharp reductions in fuel consumption in the regulated area and a considerable emission spillover in unregulated waters. Despite these adjustments, the rule generates net benefits of close to $1 billion over 29 months because the emission spillovers occur in low marginal damage areas.

The logistics of maintaining a fuel supply is a significant consideration for the military. Members of the North American Treaty Organization (NATO) prefer to use a single fuel to avoid problems with fuel transport and storage. Thus, we chose the kerosene-based F-34 jet fuel as the “single fuel” for testing on a land-based vehicle. We examined the feasibility of using F-34 jet fuel in a diesel engine and compared the performance of the jet fuel with a conventional F-54 diesel fuel. We compared the power and torque characteristics of an M52 diesel engine, as well as fuel consumption as a function of engine speed and torque using F-34 jet fuel and F-54 diesel fuel. Moreover, wear of the fuel pumps in Magirus Unimog and MAN trucks was measured during long-term tests operating with F-34 and F-54 fuels, respectively. We found that there was no obvious difference in engine power and torque using F-34 or F-54 fuel.

Aircraft taxiing in large airports is often delayed by traffic conflicts. The increased fuel consumption and pollutant emission lower the efficiency of airport surface operation and bring potential...

Recent studies have concentrated on environmental and economic impacts of ships. In this regard, fuel and C O 2 emission is considered as one of the important factors for such impacts. In particular, the sailing speed of the vessels affects the fuel consumption and therefore the emission directly. In this study, we consider a speed optimization problem in inland waterway, which is characterized by stochastic waiting times at the lock caused by uncertainty in lock processing time estimations of other vessels. The objective is to minimize fuel consumption of an approaching ship, such that it traverses the river segment in a set deadline. We introduce a mathematical model for this problem and evaluate the effectiveness and attractiveness of two solution approaches: an optimal solution and a simple heuristic. This creates intuitive guidelines for skippers based on information provision to select an appropriate speed decision approach to minimize the total expected fuel consumption and C O 2 emission of inland waterway transportation.

Jaggery, an unrefined sweetener is prepared by continuous heating of fresh sugarcane juice in different types and capacities of old indigenous and modified plants. The old indigenous plants manufactured by the rural people without any technological advancements have very high fuel consumption (about 3 kg/kg to 4 kg/kg of jaggery produced) and low heat utilization efficiency (15% to 29%). Number of modifications have been suggested by the researchers for the optimization and improvement in the performance parameters of jaggery making processes and plants. The implementation of fins at the external bottom of pans, preheater and economiser in the chimney, efficiency booster in the furnace, freeze pre-concentration system, forced draft through the plant and controlled fuel feeding in the furnace are reported to improve the thermal efficiency in the range of 25% to 50% and reduce the bagasse consumption in the range of 1.75 kg/kg to 2.75 kg/kg of jaggery prepared. The recently published article adopting novel techniques of internal preheating of sugarcane juice in the gutter pan and automatic supply of bagasse in the furnace of a two pan jaggery making plant is claimed to improve the heat utilization efficiency up to 65% and reduce the fuel consumption up to 1.50 kg/kg of jaggery produced with an affordable investment. The present paper summarizes the various technological up-gradations adopted and tested by the researchers for the enhancement of various output parameters of jaggery making units.

The industrial sector is one of the biggest oil consumers in Cyprus, corresponding to 20% of the fuel consumption. A parabolic trough collector (PTC) system seems the best option to produce clean thermal energy at higher temperatures than those that can be achieved from the already widely used flat plate collectors on the island. This paper presents a simulation model built to investigate the performance of the first industrial PTC system in Cyprus, installed at the Cyprus biggest soft drinks factory. The simulation model is built in TRNSYS and is validated using data from the real PTC system installed at the factory. The results show a very good fitting between the operating parameters and the power output of the Solar Field (SF), Concrete Thermal Storage System (CTES), and the Steam Generator (SG). The average percentage relative error of the system's contribution to the process is less than 6.32% for the daily steam production and during a week did not exceed 6.45%. The novelty of this study is the development of a design tool that can be used by potential interested industries to identify the suitable system that fits their needs. All data are provided in the form of graphs and allow anyone to use as input data the thermal energy demand and required steam temperature of the industry to retrieve information about the size of a suitable system which satisfies these requirements depending on each case. The payback period for all cases examined varies from 2 to 6 years, depending on the size of the system.

In this paper, role of heavy duty vehicles in contributing pollution is addressed with identified areas of improvement for enhancing their existing fuel efficiency. Potentials of thermo-electric generator (TEG), piezoelectric generator and regenerative braking are studied. It is suggested to develop integrated solution having all three technologies to harvest the waste energy through various means. This solution brings the individual little energy harvested through the three discussed solutions together and supply back the significant amount of energy back to the HDV’s. Combined energy harvest is suggested to optimize the cost involved and reduce the losses as well as maintenance expenses by indirectly increasing the life of associated components of the vehicles. These technologies have several limitations related to efficiency and materials which may further get improvised with the research in future.

Concern over growing fossil fuel depletion has led to the search for renewable fuels with efficiencies comparable to those seen today for conventional fuels. The present article discusses the potential and opportunities to be used in various applications for alternative fuels. The properties of these fuels and their fuel efficiency are discussed in detail. Vegetable oils provide a very positive scenario for fossil fuels to be used as alternatives. The use of biodiesel leads to a major reduction of unburned hydrocarbons, carbon Monoxide, particulate matter and nitrogen oxides in traditional diesel engines. Different alternative fuels have been compared to traditional fuels and it is clear that the use of these fuels can be greatly reduced by the use of blended fuels. Many alternative fuels have properties close to those of conventional fuels, so it is already well known the technologies needed to deal with them. Hydrogen is an exception, and its ignition characteristics differ considerably from those of conventional fuels. Therefore, difficulties in the storage, transport and use of hydrogen as a fuel are important. Therefore, difficulties are essential in storing, transporting and using hydrogen as fuel. There is also discussion of other technologies, such as alternate routes to conventional fuel alternatives, such as CTL. The discussion on emulsified oils, including the use of oxygenates, eventually took place.

The growing price of fossil oils, the gradual decline of petroleum supplies and the unsustainable emissions of motor vehicles led researchers to look for substitute fuel, such as waste lubricant oil and waste transformation oil (WTO). In power transformers, welding transformers, and electromotive systems, a significant volume of transformer oil is used as a coolant. The electrical transformer is an integral part of electrical power transmission and distribution equipment used in smaller, intermediate and larger electrical distribution stations. The efficiency and lifespan of an electrical transformer depend upon the transformer’s efficient cooling and insulation. During the working of a transformer, transformer oil is exposed to electrical and thermal stress due to which it started to degrade after some time. Thus a huge amount of degraded transformer oil is rejected as waste. The paper details the utility of waste transformer oil by using simple batch distillation operation at atmospheric pressure by analyzing the physiochemical properties of the product. The treated transformer oil is further tested in the diesel engine to examine fuel efficiency. Diesel engine runs were performed with various combinations of blends consists of diesel fuel and treated transformer oil. Results reveal that brake thermal efficiency of the blends found at 10%, 20%, 30% and 40% is 28.19%, 27.52% 26.21% and 25.98% respectively. The brake specific fuel consumption of blends at 10%, 20%, 30% and 40% is 0.29 KJ/Kwhr, 0.30 KJ/Kwhr 0.31 KJ/Kwhr and 0.315 KJ/Kwhr respectively.

The European transportation sector employs 10 million people and accounts for 4.6 % of the European Union GDP. Due to climate change, this workforce is increasingly affected by high temperatures and radiant loads, particularly during summer. They rely on air conditioning (AC) to minimize heat inside the truck cabins, increasing fuel consumption and tailpipe emissions. Because sustainable transportation is crucial for climate change mitigation, we developed a numerical investigation on the dynamic thermal exchanges of cabins of heavy-duty trucks in realistic conditions of a summer workday, to quantify the potential impact of interventions in the glazing and paint optical properties, over the truck AC loads. We observed that the changes in air temperature and solar irradiation throughout the workday imply substantial variations in the truck���s AC loads and, consequently, in its fuel consumption and tailpipe emissions. Furthermore, windshields and side windows with transmissivity of 0.33 instead of typical 0.79 and 0.84, respectively, can reduce AC loads by up to 16 %. External paints with reflectivity of 0.70 instead of 0.04 can reduce the AC loads by up to 30 %, whereas cumulative changes to glazing and paint can reduce the AC load by up to 40 %. These interventions can lower fuel consumption and emissions by up to 0.4 %. These results show that important improvements in fuel efficiency and tailpipe emissions are possible, if the research community, policy makers and industry stakeholders successfully promote the adaptation of the European transportation fleet.

This paper investigated the techno-economic viability assessment of solar PV/wind/diesel generator (DG)/battery hybrid energy systems (HES) for powering an isolated rural health clinic in northern Nigeria. HOMER–software tool developed by the US National Renewable Energy Laboratory (NREL) has been utilized for the techno-economic assessment of the proposed HES. The results of the simulation reveal that PV/DG/battery HES with 5.43 kW PV, 2 kW DG, 3.06 kW power converter, and 10 units of batteries emerged as the optimum system and most preferable with the minimum Net Present Cost (NPC) of $16,457 and Cost of Energy (COE) of $0.259/kWh compared to other system cases. The outcome also shows that the optimized solution is environmentally friendly as it presented an acceptable carbon dioxide emission of 1304 kg/year, which was about 80% and 82.5% less than that of system case 3 (DG/battery) and system case 5 (DG-Only). To have a good understanding of the operation of various system configurations considered, details of the system’s battery storage status and power flow are discussed via the energy balance of the various system configurations. This analysis shows operating cost, fuel cost, COE, fuel consumption, and renewable fraction are sensitive to the variation in all the considered sensitivity parameters.

Many biomass power plants are not flexible, using only one fuel type, and have high CO2 emissions. In this study, a new methodology to assess the multi-biomass utilization for a power plant is proposed. The results provide that the proportions of mixed biomass residues in different regions of Thailand are appropriate with lower chloride content and slagging inclination than the standard specification. However, high alkali metal oxides in biomass in the southern region lead to high fouling inclination with high fly ash deposition. The electricity production using multi-biomass fuel is more efficient with lower fuel consumption than that with single-type biomass. To generate 103.43 MW electricity production, 107.89 t h−1 consumption of mixed biomass fuels in the central is lower than that with multi-biomass in other regions. However, it generates a maximum of 12.5 mol% CO2 in exhaust gases which can be captured by suitable amine-based absorbents with 90.82% efficiency.

In this study, a new hybrid solar preheating intercooled gas turbine (SP-IcGT), is presented, in which a parabolic trough solar technology is used to preheat the compressed air before entering the combustor. The performance of the new hybrid gas turbine was evaluated and compared with the conventional hybrid solar preheating gas turbine (SP-GT). Several performance indicators were used in the analysis under Guangzhou (China) weather data. It is observed that the SP-IcGT is superior to the SP-GT system as it can boost the fuel-based efficiency by 19.35% versus 0.26% for the SP-GT system. In addition, the SP-IcGT has a much lower specific fuel consumption (about 7017 kJ/kWh) compared with the 10362 kJ/kWh for SP-GT. The highest fuel-based efficiency of 51.4% is obtained for the SP-IcGT with 47.4% improvement over the SP-GT, which exhibits a levelized electricity cost of 4.58 US/kWh. Meanwhile, fuel consumption and greenhouse gas emissions can be reduced greatly by integrating solar energy with the intercooled gas turbine. The SP-IcGT is more economical than applying carbon capture to the equivalent conventional gas turbine plant combined while achieving the same reduction of CO2 emissions. Overall, the SP-IcGT is an attractive system under different climates.

The source of electricity supply in isolated areas is commonly from diesel or other fossil fuel-based generation systems. However, the increasing cost and harmful emissions of these fuels have led researchers to seek alternative solutions in providing electricity. Hence, harnessing renewable resources can be a favourable solution in lowering the dependency on fossil fuels. The Strait of Malacca is blessed with tidal current energy, a research was conducted to design a hybrid renewable energy system (HRES) that consists of tidal current and solar energy as its sources along with backup power such as generators to support the electrical demand of a lighthouse. A simulation method is used to determine and compare the optimal configuration of the HRES with the diesel generator-based system. An evaluation of all possible scenarios of standalone systems was carried out by considering the amount of fuel consumption and pollutant emittance, capacity shortage, excess electricity production, unmet energy and renewable fraction parameters of each system scenario. From the findings, the hybrid energy system of Scenario A that consists of tidal turbines, PVs, generator, battery, and converter produces better results where the diesel fuel consumption can be reduced up to 84% in comparison with the standalone generator-based system.

The contribution of the tire-road slip of traction wheels to the total resistance opposing the motion of a light-duty commercial vehicle has been investigated through the simulation of several homologation and custom driving cycles. The calculation of the contribution of the tire slip losses was based on the estimation of the longitudinal tire slip, by means of Pacejka’s MF5.2 tire model. In this work, the computational steps required to evaluate this contribution were implemented in a previously developed fuel consumption simulation tool. Simulations were performed under several vehicle loading conditions and tire inflation pressures on traction and non-traction wheels, and considering different tire-road adherence conditions, in order to obtain a characterization of the tire slip losses over a wide range of working conditions. An analysis of the results shows that, although the contribution of tire slip losses to the total vehicle energy demand and fuel consumption may be relevant – especially under low-load, low adherence conditions – the sensitivity of the average on-cycle vehicle energy/fuel consumption to changes in the tire inflation pressure is only affected slightly by tire slip losses. Therefore, tire slip losses can be neglected in practice, when the aim of a simulation is to optimize the tire pressure to achieve average vehicle working conditions over a driving cycle.

With incessant increases in fuel prices worldwide and concerns for environmental pollution, the need for alternative sources of energy is becoming urgent. In this study, the potential of grape seed oil for biodiesel as an alternative fuel was evaluated. Refined grape seed oil was bought in liquid form and then subjected to an alkali-catalyzed transesterification process for biodiesel production. The physicochemical properties of the resulting biodiesel—namely, viscosity, cetane number, and heating value—were investigated. The biodiesel was blended with a conventional diesel in various proportions and combusted in a four-cylinder, four-stroke compression ignition (diesel) engine under two loading conditions. Experimental results revealed that the blend ratio of B70 (70% GS biodiesel and 30% conventional diesel) gave the best overall engine performance in terms of maximum power, minimum emissions, and fuel consumption. Furthermore, a novel neural network technique called extreme learning machine was adopted to investigate the optimal blend ratio using the dataset obtained from the experimental results. The results also indicate that the best choice of biodiesel blend ratio is approximately B73.67 (73.67% GS biodiesel and 26.33% conventional diesel). The study shows that grape seed oil could serve as a reliable source of production of quality biodiesel fuels, which could be used as an alternative to conventional diesel fuels.

Fuel is something that is very important in everyday life. Almost every human being needs fuel to meet their needs and support their activities, for example cooking in household needs. Currently, fossil fuels or fuel oil (BBM) are still widely used to meet demand, however, it should be noted that fossil fuels or fuel oil (BBM) are non-renewable natural resources. The biomass rocket stove is one of the modern stove innovations that uses biomass energy as the main energy source. Rocket stoves are designed to increase fuel efficiency with thermal efficiency, a combination of the increased combustion efficiency and heat transfer associated with burning briquette fuel. The purpose of this research is to design and manufacture rocket stove fired with coconut and bamboo biomass for household needs as well as developing methods and equipment for performance testing of rocket stoves. In this study, several steps were carried out, including designing a rocket furnace, selecting biomass fuel and testing the performance of a rocket furnace. From the design of the biomass stove, it is noteworthy that the design with two holes makes the combustion air easily enters and makes combustion in the furnace more perfect and efficient. Water boiling test using three types of solid fuels with the cold start condition suggested that the highest thermal efficiency was coconut fronds with a value of 38% and the lowest thermal efficiency was found from coconut shell combustion, i.e. 22%. During hot start test, the highest thermal efficiency was obtained from coconut fronds firing with a value of 41%. Moreover, with simmer water boiling test method, firing the rocket stove with coconut fronds showed the highest thermal efficiency with a value of 37%. Keywords: Rocket Stoves, Coconut Fronds and Shells, Bamboo, Thermal Efficiency, .Water Boiling Tests.

Traffic as the main source of urban air pollution created severe problems for human health and sustainability. To propose a bottom-up method in emissions reduction, accurate emission inventories of vehicles in a medium-sized city are developed. Traffic emission factors were obtained using traffic flow data, traffic control cameras, and International Vehicle Emission (IVE) model to calculate CO, VOCs, NOx, SOx, and PM of passenger cars, taxis, and urban buses emission inventory. Annual overall emissions of CO, VOCs, NOx, SOx, and PM pollutants, respectively, are 346, 20.9, 25, 44.4, and 0.5 kt/year. VOC and CO emissions in the start-up phase are in the scale of the running phase, while NOx, SOx, and PM allocate much less than the running phase. The highest emission value of SOx and PM occurs in arterials while CO, VOC, and NOx in highways. Eight renovation scenarios have been designed to evaluate their environmental and economic efficiency. Two scenarios entitled "renovation of carbureted, Euro 1 and Euro 2 LDV" and "renovation of high mileage Euro 1 and Euro 2 standard urban buses" showed the highest decrease in pollution emission and pollution social costs. For these two important scenarios, implementation costs were calculated at 477 and 46 M$, while social costs decrease are calculated to be 172.6 and 77.5 M$, respectively. Renovation of vehicles could benefit both the government and society by reducing fuel consumption and pollutant emission. The emission mitigation scenarios considering mobile sources could be a guide for adopting policies in developing countries. Governmental and social cost-share and governmental and social repayment because of fuel-saving costs have also been calculated.

The use of biofuels in vehicles becomes more advantageous than the consumption of fossil fuels, mainly because it uses renewable sources of energy. Recently there are some concerns about biodiesel sources, and hydrotreated vegetable oils (HVO) appear as a possible advanced solution. To understand the effect that the implementation of the new and old European type-approval test cycles (NEDC e WLTP) has on the results of these fuels considering pollutant emissions and fuel consumption results, a EURO V vehicle was subject to these cycles and also to engine performance evaluation tests. For this analysis, the fuels considered were: B0 (pure diesel), B7 (7% of biodiesel), B15 (15% of biodiesel), B100 (pure biodiesel), and HVO15 (15% of HVO). The findings lead to the conclusion that completely replacing fossil fuels with biofuels is not the most cost-effective approach. No significant differences were observed considering the two homologation cycles, the oldest (NEDC) and the actual (WLTP) and the use of HVO also does not present any relevant differences concerning the fuel consumption differences to B0 (+0.58% NEDC and +0.05%WLTP), comparing well with biodiesel behavior (−1.74% NEDC and −0.69%WLTP for B7 and +1.48% NEDC and 1.89% WLTP for B15). Considering the power of the engine obtained with the fuels, the differences are almost negligible, revealing variations smaller than 2% for B7, B15, and HVO15.

The basic criterion In using alternative fuels, specifically ethanol blends, consists in its pro-ecological properties. However, like in the case of conventional hydrocarbon fuels, the use of blended ethanol in combustion engines can result in formation of harmful engine deposits. The addition of DCA (Deposit Control Additive) type fuel improvers is the most effective approach to prevent harmful deposit formation. However, such additives, although widely used in engine petrol types, are usually not fully compatible and hence effective in the case of ethanol fuels. Because of this, an effective DCA was developed under the carried out project, dedicated to ethanol fuels. The project was aimed at carrying out a comparative assessment of the impact of the developed DCA additive to ethanol fuels on engine emission and fuel consumption. Using a chassis dynamometer test with exhaust gas analyzers and Fourier-transform infrared spectroscopy, regulated emissions of CO, NMHC, HC, THC, NOx and PM, PN were investigated, as well as CO2, and unregulated emissions of CH4, HCHO, MeCHO, NH3, ETOH. This allowed evaluating, whether the use in ethanol fuels of a new DCA, of effectiveness confirmed in tests, creates a threat in the field of increased emission of a combustion engine supplied with so improved fuel.

As an emerging technology improving fuel consumption, active grille shutter (AGS) has been applied in engine cooling system. For the reason of unreasonable matching method of grille opening and cooling fan, the problem of engine overcooling is widespread. As components with similar function of adjusting cooling air flow, the AGS and the cooling fan are separated from each other in parameter matching and operation which reduce cooling efficiency and fuel economy. To achieve precise cooling and improve fuel economy, a joint control strategy for AGS and cooling fan was proposed by using computational fluid dynamics. In order to verify the feasibility of the strategy, the fuel economy tests were carried out at 0 km/h, 90 km/h and 120 km/h, respectively. The results showed that the fuel consumption under the three working conditions was reduced by 0.01 L/100 km, 0.07 L/100 km and 0.13 L/100 km, respectively, indicating that the proposed strategy can significantly reduce fuel consumption.

Restricted resources of fossil fuels together with exhaust-gas emissions dilemma led to looking for the promising solutions to increase the engine’s efficiency and decrease the fuel consumption. Substituting the biodiesel instead of diesel oil as well as using additives, have been introduced as reliable solutions to increase the engine efficiency and reduce the emissions. In this experimental work, the various concentrations of cerium oxide nano-particles (i.e. 60 ppm, 90 ppm and 120 ppm) were added to diesel/biodiesel fuel blend and their effects on energy and exergy efficiency are examined on the single cylinder in-direct injection diesel engine. Results revealed that B0W5N60 (diesel containing 5% water and 60 ppm NPs) has 2.5% higher brake thermal efficiency compared to pure diesel. Also, B0W5N90 and B0W5N120 lead to 3.8% and 4.7% improvement in brake thermal efficiency compared to diesel, respectively. By adding the nano-particles into the fuel samples, brake specific fuel consumption is enhanced; Results indicated that brake specific fuel consumption of B0W5N120 and B5W5N90 are 1.05% and 0.42% lower than that of B5W5N60, respectively. Increasing the nano-particles concentration has the increasingly effect on the exergy efficiency for all amounts of biodiesel. For B0 fueling cases, the maximum exergy efficiency of the engine belongs to the B0W5N120 (36.6%) while minimum amount is assigned to the B0W15N60 (31%).

A CCHP is modeled here, which is operated based on thermal energy provision because the target consumer demands more heat and cooling than electricity. The main components of the CCHP system are a PEMFC as the main generator, absorption chiller, electric chiller, and auxiliary boiler. The fuel consumption, cost, and carbon release improvements compared to a separated generation system (SGS) are maximized in this system using the proposed modified mayfly algorithm. The system design and operation are optimized in two different stages. A hotel building has been chosen as the case study to demonstrate the effectiveness of the proposed CCHP system and optimization in comparison to the traditional mayfly algorithm (MA) and genetic algorithm (GA). The proposed optimization algorithm has performed 8.15% and 10.06% better compared to MA and GA, respectively. It also reached its solution in far shorter time. The optimum size of PEMDC and share of auxiliary chiller (AC) in cooling provision is determined to be 548 kW and 43.1%, respectively. It is shown that improvement achieved by using the AC in the CCHP is increased by 23.21% compared to a CCHP without one. Furthermore, the AC make the improvement of CCHP more constant and robust to load variation. Moreover, the sensitivity of the optimum operation condition of the CCHP against the electricity and fuel price changes and share of the AC in supplying the cooling demand are studied to provide the system operators with the necessary tools needed to optimally handle price changes.

The low-sweep transonic natural laminar flow wing with shock control bumps, namely, LS-NLF-SCB wing, has a promising potential to be applied to future narrow-body commercial aircraft due to its adv...

This paper presents a conceptual study of a regional aircraft with a turboelectric propulsion system and boundary-layer ingestion. The aircraft has an additional electric propulsor installed at the...

Owing to enormous increase in the automobile population, traditional petroleum fuels for internal combustion engines will be usable only for a few years. Moreover, by releasing toxic emissions into the atmosphere at higher levels these fuels create severe environmental problems. In general, Carbon-monoxide (CO), Unburnt hydrocarbons (UHC), and smoke are emissions emitted by engines. The pollution of the environment can be controlled by replacing petroleum fuel with the use of alternative fuels like acetylene gas, hydrogen, CNG, LPG etc. In this current research, an experimental investigation was carried out in Compression Ignition engine using acetylene fuel, further enhancing the performance and emission properties by using diethyl ether (DEE) and ethanol as oxygenated fuel. In view of the performance and outflow (emission) parameters optimizing valve of acetylene gas as 12 lpm with oxygenated fuels, the performance and outflow characteristics were improved. The findings show an enhancement in brake thermal-efficiency of up to 3 to 4%, a decrease in exhaust temperature and emissions like CO, UHC and smoke of up to 40%, 20%–30% and 10%–35% respectively, there is decrease in fuel consumption of 10%–30%. It was found that ethanol is better than diethyl ether and diesel fuels when used as an oxygenated fuel with acetylene gas. In view of the performance and emission parameters, the best oxygenated fuel is ethanol and the optimize blend for diesel engine is E15+A12.

Currently micro/nano satellites have become the protagonists in most formation flying missions, and there is an urgent demand to propose a reliable approach for quick fuel estimation of multiple-impulsive scheme on-board to achieve formation reconfiguration problems. This paper presents an optimal control approach based on multiple impulses for satellite formation in-plane reconfiguration issue in near circular orbit. Based on initial small deviation in the cylindrical coordinates system, a relative orbit motion expression is investigated, and a time-varying propagate system without perturbation is presented in this paper, which is suitable to calculate the solution of relative orbital maneuver by multiple impulses. The formation reconfiguration problem of this relative orbit motion is considered, and orbital motion equations with initial deviations are presented for relative orbital transfer calculation. Through different combinations of method from normal four-impulsive solution, the optimal three-impulsive method for relative orbital transfer in plane is obtained by analysis solution based on graphical and numerical way. In the end of paper, the effectivity and optimality of method is validated, and fuel consumption is analyzed through simulations of assumptive different formation reconfiguration missions.

The paper analyzes the energy consumption of an energy-independent house in two different situations, namely when the exterior insulation is installed and, respectively, in its absence. The result of the analysis was used to assess the reduction of fuel consumption and greenhouse gas emissions of the auxiliary heating system, namely a biomass boiler. The home’s heating system consists of a Stirling cogeneration system with biogas, which produces 3 kW of electricity and 9 kW of heat, and a 50 kW biomass boiler. The biomass boiler must provide the additional heat necessary to cover the consumption of the house when the Stirling engine is running and respectively ensure the coverage of the complete heat consumption of the building when the Stirling engine is in standby mode. The analysis showed that the installation of external insulation on the building walls will reduce energy consumption by 13%–16%, depending on the variation of the outside air temperature.

Internal combustion engine vehicles are a key factorin the actual economy and is expected to continue the growth indemand for vehicles using gasoline. Gasoline, like other fossil fuels,is a non-renewable resource whose reserves are constantlydeclining. Due to this reason, to improve the efficiency and toreduce emissions is of great importance for energy reserves andenvironmental protection. There are vehicles with hybrid systems and other technologies that reduce fuel consumption andpollutants generation, however most of the vehicles do not have or they are not compatible with the new technologies. This work proposes to enrich gasoline by adding hydrogen to the mixture of fuel and oxygen in order to improve combustion and reducepollutants. Hydrogen is regarded as a promising alternative fuel for internal combustion engines, which unlike fossil fuels, it can be generated by renewable energy. On the internet there is a set of experiments with alkaline electrolyser, generating oxyhydrogen for fuel enrichment. However, the design and development of a control system, specifically designed for the dynamic performanceof an electrolyser, is not commonly found in the scientificliterature. The main approach of this paper is to design and build a power conditioning stage based on synchronous buck converteris used to provide supply power to an alkaline electrolyzer thatproduces hydrogen and oxygen with up to 99 % purify.

Application of diesel fueled partially premixed compression ignition (PPCI) engines are limited due to its excessive pressure rise rate at high load. Multiple premixed compression ignition (MPCI) engines fueled with low octane number gasoline (LON) has the potential to operate at both low and high load, while effects of split injection strategy on performance of such engines have not been discovered yet. In the present study, comparisons of LON and commercial diesel are first conducted in a heavy-duty single cylinder engine. Then, pilot injection timing and main injection timing are varied individually to reveal their effects on the combustion, emission, and economic performance of the MPCI engine. Comparing with diesel, MPCI engines with LON merits a low pollutants emission due to the long ignition delay and good volatility of LON. Split injection strategy can reduce the NO x and PM emissions simultaneously for MPCI engine with LON, and also reduce fuel consumption.

Water injection in internal combustion engines is mainly used for additional cooling of the combustion chamber and knock suppression. The main advantages of the water injection are the potential for the enhancement of the performance of the engine. Studies conducted so far have aimed to track engine performance at maximum load and fuel consumption (brake-specific fuel consumption BSFC). Specialized literature is less consistent as regards to the injection of water at medium and low loads. This work monitors the effects of water injection at medium loads and the evolution processes of the four-strokes in the engine with and without water injection. A side-valve, air cooled natural aspirated engine with water and fuel injections in the intake manifold was used for this study. The work during expansion was increased, but this trend was reversed by the higher loads required during intake, compression and exhaust strokes, leading to a reduction in the indicated efficiency when water was injected.

This article analyzes the losses, efficiency and fuel consumption of the generating units during the process of producing active and reactive energy. It presents a proposal for tests to determine the losses of the generating units already installed in the plants, proved by the actual application in a hydroelectric generating unit and in a thermoelectric generating unit. The result obtained in the study is a general equation of losses as a function of the simultaneous generation of active and reactive power that were determined through the variations of the armature and field currents and the terminal voltage of the generating unit, which can be represented by a three-dimensional graph showing total losses at all possible operating points. Losses have a direct influence on the efficiency of each component of the generating unit, directly influencing fuel consumption at the many allowable operating points. The study also showed the fuel consumption and loss curves in real hydroelectric and thermoelectric generating units installed in Brazil. With the determination of efficiency at each point of operation, it allows determining a weighting factor based on the value of the active and reactive energy generated, culminating in the proposition of an index that reflects the total production cost of each generator for an entire power plant. This makes it possible to divide the requested active and reactive energy in detail between less expensive generating units of the same hydro or thermal generating plant

This work presents the results of a study to optimize the production of electricity, by hybrid system Photovoltaic – Diesel – Batteries, to power the village of Kalakala in the north of Côte d'Ivoire. The study site is an isolated rural community, powered by a diesel generator. It is located in northern Côte d'Ivoire. HOMER software has been used for system simulation and optimization. The result of this study is then compared to those of PV - Batteries and diesel alone systems. From the results of the simulations, it appears that the optimal combination of the hybrid system includes a diesel generator of 50 kW, a photovoltaic field of 46 kW, 10 batteries of 48V and a converter of 100 kW. With a photovoltaic penetration rate of 52.7%, this system, compared to the photovoltaic - batteries system, reduces the photovoltaic field by 56%, the number of batteries by 61.5% and increases battery life by 42.84%. Compared to diesel alone, it reduces fuel consumption and the quantity of CO2 by 60% and improves diesel efficiency by 17%. The cost of generating electricity for the hybrid system is €0.373/kWh compared to €0.466 and €0.608/kWh respectively, for the PV-Batteries and diesel alone systems. The hybrid system with the best technical, economic and environmental performance could be a good alternative for generating electricity in remote communities.

Purpose The purpose of this paper is to calculate the fuel consumption and emissions of carbon monoxide (CO), nitrogen oxide (NOx) and hydrocarbons (HC) in the taxi-out period of aircraft at the International Diyarbakir Airport in 2018 and 2019. Design/methodology/approach Calculations were performed by determining the engine operating times in the taxi-out period with the flight data obtained from the airport authority. In the analyses, aircraft series and aircraft engine types were determined, and the Engine Exhaust Emission Databank of the International Civil Aviation Authority (ICAO) were used for the calculation. Findings Total fuel consumption in the taxi-out period in 2018 and 2019 was calculated as 525.64 and 463.69 tons, respectively. In 2018, HC, CO and NOx emissions caused by fuel consumption were found to be 1,109, 10,668 and 2,339 kg, respectively. In 2019, the total HC, CO and NOx emissions released to the atmosphere during the taxi-out phase are 966, 9,391 and 2,126 kg, respectively. B737 Series aircraft have the largest share in total fuel consumption and pollutant emissions. Practical implications This study explains the importance of determining fuel consumption and pollutant emissions by considering engine operating times in the taxi-out period. The study provides aviation authorities with scientific methods to follow in calculating fuel consumption and emissions from aircraft operations. Originality/value The originality of this study is the calculation of fuel consumption and pollutant emissions by determining real-time engine running times in the taxi-out period. In addition, calculations were made with real engine operating times determined in the taxi-out period using real flight data.

Alternative fuels have attracted wide attention owing to the increasing energy consumption and environmental pollution problems, which are caused by the extensive application of diesel engines for various occasions. The Fischer–Tropsch (F–T) diesel synthesized from coal is considered as one kind of ideal alternative fuel for diesel engines; however, its combustion and exhaust emission characteristics are different from those of national diesel owing to its special fuel properties. Therefore, the combustion and emission characteristics of F–T diesel and 0# diesel, which meet the China stage VI were compared in a common rail direct injection (CRDI) diesel engine. Moreover, energy-saving and pollution-reduction potential were analyzed in one CRDI diesel engine fueled with F–T diesel. The results showed that F–T diesel had an earlier ignition point, shorter ignition delay, lower cylinder pressure, and heat release rate compared with those of 0# diesel at the same operating conditions. Meanwhile, the amplitude, oscillation level, and energy of cylinder pressure were decreased to some extent, with the maximum drops of 0.98 bar, 16.4 dB, and 1.01 × 1012 Pa, respectively. Additionally, under external characteristic conditions, maximum break thermal efficiency (BTE) and break-specific fuel consumption (BSFC) of F–T diesel were reduced by 1.1 and 2.1% on average compared with those of 0# diesel. In addition, CO, HC, NOx, and SOOT emissions of F–T diesel were found to be lower than those of 0# diesel, which were decreased by an average of 8, 3.7, 2.1, and 1.3%, respectively.

Growing environmental concern prompts vehicle users to search for cleaner and ecological transport modes. Many consumers and organizations have decided to replace conventional diesel or gasoline powered vehicles with alternative drive or alternative-powered vehicles. Operating conditions may have a heavy influence on the operating parameters of vehicles, such as: airpollution emission, energy consumption and fuel consumption. This paper presents a comparative analysis of the life cycle of conventional and hybrid drive vehicles in various driving conditions. The presented LCA results show that replacing a conventional diesel or gasoline vehicle with a hybrid electric drive vehicle results in approximately 40 % lower total lifetime air-pollutant emissions than those of conventional drive vehicles in urban driving conditions.

Road transport is the primary source of atmospheric air pollution, thus posing a threat to human health and life. The aim of the study was to determine the impact of fuel obtained from plants on the ecological properties of a compression ignition engine. The article reports the results of investigations into a modern engine with a Common Rail system, powered by the RME (rapeseed methyl esters) biodiesel and their blends with diesel. For comparison, the engine was also fuelled with conventional diesel oil without ester addition. When powering the engine with blends and pure biodiesel, brake specific fuel consumption increased. The concentrations of nitrogen oxides and carbon dioxide in the engine exhaust gas also slightly increased. At the same time, a clear reduction in average concentrations of carbon monoxide, hydrocarbons and particulates matter was obtained.

Road transport have significant impact on regional economic and social development, but one can also point out a number of its disadvantages, which include environmental pollution. The paper presents measurements of fumes exhaust emissions of a passenger car with a significant operational mileage. The tests were carried out in a laboratory on a chassis roller dynamometer using various driving cycles. To determine the exhaust emissions, data on the mass of air flowing through the intake manifold was used, among others. The work also describes an example of own driving cycle developed based on urban driving in Lublin, Poland.

Station-keeping (SK) is indispensable in actual geostationary (GEO) satellite missions. Due to the luni-solar gravity perturbations, the inclination of a GEO satellite suffers the issues of secular drift and long-period oscillation. Current north-south (NS) SK strategies maintain the GEO satellite’s orbit with high accuracy but low fuel efficiency. In this work, an efficient high-accuracy NS-SK strategy is developed for the GEO satellites. First, an averaging method is employed to decrease the accumulation of the secular drift within a one-solar-day SK cycle, while the long-period oscillation caused by the solar gravity is damped to further improve the orbital accuracy using the impulse and finite-thrust propulsions. Second, we contribute a fuel-optimal cycle that reduces the fuel consumption and a fixed-interval cycle that executes SK control in fixed time interval every day to further enhance the proposed NS-SK strategy. Numerical simulations show that the improved strategy can achieve high-accuracy NS-SK with little fuel consumption. Moreover, results also demonstrate that the fixed-interval cycle can reach higher NS-SK accuracy while consuming less fuel.

In Canada, fire behaviour is modelled based on a fuel classification system of 16 fuel types. Average fuel loads are used to represent a wide range of variability within each fuel type, which can lead to inaccurate predictions of fire behaviour. Dead and down woody debris (DWD) is a major component of surface fuels affecting surface fuel consumption, potential crown fire initiation, and resulting crown fuel consumption and overall head fire intensity. This study compiled a national database of DWD fuel loads and analysed it for predictive driving variables. The database included DWD fuel loads for all dominant Canadian forest types at three size classes: fine (7 cm). Predictive models for DWD fuel load by size classes individually and collectively for various forest types and ecozones were analysed. Bioclimatic regime, age, spatial position, drainage, and structural components including diameter at breast height and stem density were significant variables. This study provides tools to improve our understanding of the spatial distribution of DWD across Canada, which will enhance our ability to represent its contribution within fire behaviour and fire effects models.

The World-wide harmonised Light-duty Test Cycle (WLTC) was developed internationally for the determination of pollutant emission and fuel consumption from combustion engines of light-duty vehicles. It replaced the New European Driving Cycle (NEDC) used in the European Union (EU) for type-approval testing purposes. This paper presents an extensive comparison of the WLTC and NEDC. The main specifications of both driving cycles are provided, and their advantages and limitations are analysed. The WLTC, compared to the NEDC, is more dynamic, covers a broader spectrum of engine working states and is more realistic in simulating typical real-world driving conditions. The expected impact of the WLTC on vehicle engine performance characteristics is discussed. It is further illustrated by a case study on two light-duty vehicles tested in the WLTC and NEDC. Findings from the investigation demonstrated that the driving cycle has a strong impact on the performance characteristics of the vehicle combustion engine. For the vehicles tested, the average engine speed, engine torque and fuel flow rate measured over the WLTC are higher than those measured over the NEDC. The opposite trend is observed in terms of fuel economy (expressed in l/100 km); the first vehicle achieved a 9% reduction, while the second – a 3% increase when switching from NEDC to WLTC. Several factors potentially contributing to this discrepancy have been pointed out. The implementation of the WLTC in the EU will force vehicle manufacturers to optimise engine control strategy according to the operating range of the new driving cycle.

The share of road transport accounts for more than 85% of the total structure of freight transportation. In this process, mainly motor vehicles are used to carry out the freight work. In addition to them, forklifts are also used, whose task is to load and unload goods. These vehicles are categorized as NRMM (Non-Road Mobile Machinery). Forklift trucks have internal combustion or electric drive. The paper presents an analysis of the emission of pollutants and fuel consumption from forklift trucks equipped with diesel and LPG power. The study uses the author's test taking into account the raising/lowering of a pallet, a loaded and unloaded run. The measurements were made in the warehouse and outside the warehouse using the Porstable Emission Measurement System (PEMS) equipment. The aim was to show the influence of loading conditions on the emission of pollutants and fuel consumption.

Energy, exergy, exergoenvironmental, and exergoeconomic analyses of a natural gas boosting station are presented using a real‐gas model and actual operational data. The effect of varies performance parameters on the thermodynamic efficiencies, specific fuel consumption (SFC), gas‐phase emissions, and cost rates are assessed. The results show that, for the actual operational conditions of the gas boosting station, the exergy efficiencies are 76.1% and 73.9% in the hot and cold seasons, respectively. Moreover, the energy analysis at partial load reveals that the SFC varies from 0.285 kg/kWh to 0.302 kg/kWh, respectively, in maximum and minimum ambient temperatures. The exergoeconomic analysis along with the exergoenvironmental analysis shows that the total cost rate of gas boosting stations in hot and cold ambient conditions is 7390 US$/h and 8070 US$/h, respectively, with more than 60% related to the environmental impact. In this system, the highest exergoeconomic factor is attributed to the centrifugal gas compressor at 40.9%‐44.2% and the lowest to the air cooler at 0.030%‐0.036%, depending on the ambient temperature, which specifies the balance between capital cost and the cost of exergy destruction. The cost rate of the exergy destruction is more pronounced in the combustion chamber, and the overall cost rate of the exergy destruction can be improved significantly by increasing turbine inlet temperature which needs additional investment cost for the system.

In the course of the most recent thirty years reduction of ship resistance and saving fuel consumption to accomplish higher speed with reduction of pollutants has been the significant subject for researchers. Micro bubble drag reduction technique is the one of the most interesting thoughts in this field owing to its great advantages, such as considerable potential drag reduction, easy operations, environmental friendliness and low costs. In this study a 3-D numerical investigation into frictional drag reduction by air micro bubbles is applied on KRISO container ship model. The objective is to understand the mechanism of resistance reduction through micro bubbles injection under model ship at different Froude numbers, injection rate and of course volume fractions. The numerical simulations are performed using a commercial CFD code solving Reynolds averaged Navier-Stokes (RANS) equations. For more than 36 simulations has performed to investigate the effect of injection of micro bubble under ship model hull and to estimate the local Coefficient of friction values along ship hull model. The results show that at all of the examined Froude number, frictional resistance reduction attained but at different rates and a maximum drag reduction of 27.6 % obtained at 0.282 Froude number with 4.8 % air volume fraction.