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1

Zhang, Shuo. "Diverse sustainable methods for future jet engine." Applied and Computational Engineering 11, no. 1 (September 25, 2023): 143–48. http://dx.doi.org/10.54254/2755-2721/11/20230223.

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Анотація:
With global concerns over CO2 emissions and climate change, the aviation industry is investing in renewable fuels and sustainable engines. Bio-Synthetic Paraffinic Kerosene (Bio-SPK) and hydrogen are two significant biofuels that can replace fossil fuels in jet engines. Biofuel is considered a sustainable fuel; it is possible to replace fossil fuel in jet engines. Bio-SPK is an aviation fuel made from plant-derived lipids and processed to have similar properties to traditional jet fuel. It offers significant emissions savings compared to Jet-A1 but is not widely available due to high production costs and limited feedstock availability. While it can improve fuel efficiency and reduce emissions, it has lower energy density than conventional aviation fuels, potentially reducing aircraft range or payload capacity. Hydrogen produces only water but requires careful extraction or manufacturing. Green hydrogen is carbon-neutral, grey hydrogen generates carbon, and blue hydrogen captures and stores carbon. However, most hydrogen is currently generated as grey hydrogen, which offers less environmental benefit than directly burning fossil fuels. This work provides an overview of current and future sustainable jet engine technologies.
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2

Shuaibu Alani Balogun, Ihwan Ghazali, Abdullahi Tanko Mohammed, Dhany Hermansyah, Ayu Amanah, and Mega Tri Kurnia. "Renewable Aviation Fuel: Review of Bio-jet Fuel for Aviation Industry." Engineering Science Letter 1, no. 01 (August 3, 2022): 7–11. http://dx.doi.org/10.56741/esl.v1i01.59.

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Анотація:
The search for environmentally sound, socially responsible, and economically viable renewable fuel generation methods is a major global concern. A type of aviation fuel called jet fuel or often spelled avtur is intended for use in aeroplanes with turbine (gas) engines. Jet fuel appears colourless. The fuels Jet A and Jet A-1 are the most frequently used ones in commercial aviation sector. Other than Jet B, which is utilised for its enhanced cold-weather operation, there are no other jet fuels that are frequently used in gas-turbine-engine in the aviation industry. Renewable aviation fuel or known as bio-jet fuels represent a sizable sector for the consumption of fossil fuels. The production of bioethanol and biodiesel for piston engine vehicles in internal combustion engines has already shown that biofuel can play a significant role in the development of sustainable renewable aviation jet fuel. Here, we also provide a book review on the potential bio-jet fuel as a renewable aviation jet fuel.
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3

Åkerblom, Arvid, Francesco Pignatelli, and Christer Fureby. "Numerical Simulations of Spray Combustion in Jet Engines." Aerospace 9, no. 12 (December 16, 2022): 838. http://dx.doi.org/10.3390/aerospace9120838.

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Анотація:
The aviation sector is facing a massive change in terms of replacing the currently used fossil jet fuels (Jet A, JP5, etc.) with non-fossil jet fuels from sustainable feedstocks. This involves several challenges and, among them, we have the fundamental issue of current jet engines being developed for the existing fossil jet fuels. To facilitate such a transformation, we need to investigate the sensitivity of jet engines to other fuels, having a wider range of thermophysical specifications. The combustion process is particularly important and difficult to characterize with respect to fuel characteristics. In this study, we examine premixed and pre-vaporized combustion of dodecane, Jet A, and a synthetic test fuel, C1, based on the alcohol-to-jet (ATJ) certified pathway behind an equilateral bluff-body flameholder, spray combustion of Jet A and C1 in a laboratory combustor, and spray combustion of Jet A and C1 in a single-sector model of a helicopter engine by means of numerical simulations. A finite rate chemistry (FRC) large eddy simulation (LES) approach is adopted and used together with small comprehensive reaction mechanisms of around 300 reversible reactions. Comparison with experimental data is performed for the bluff-body flameholder and laboratory combustor configurations. Good agreement is generally observed, and small to marginal differences in combustion behavior are observed between the different fuels.
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4

Gurkan Aydin, Sinem, and Arzu Ozgen. "Bio-Based Jet Fuel Production by Transesterification of Nettle Seeds." Engineering, Technology & Applied Science Research 13, no. 1 (February 5, 2023): 10116–20. http://dx.doi.org/10.48084/etasr.5556.

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Анотація:
The use of petroleum-based fuels in air transport and the increase in oil prices over the years have increased fuel costs. Due to this increase, fuel manufacturers and airline companies have started to search for alternative fuels. Since aviation has an important place in the transportation sector, biomass has the greatest potential in the search for renewable energy sources. Biological substances of plant and animal origin and containing carbon compounds are energy sources, and the fuels produced from them are called biofuels. Biofuels are an important source of sustainable energy, which greatly reduces the greenhouse gas effect, improves weather conditions, reduces dependence on oil produced from fossil fuels, and is important for new markets. The nettle seed oil used in the current study was purchased from the local market and was obtained using the cold-pressing method at low temperatures. After the completion of the transesterification process, a two-phase mixture consisting of biofuel-glycerin was obtained, and the upper phase containing fatty acids was taken and transferred to a clean tube. After the final washing processes, bio jet fuel was obtained by adding chemicals at certain rates. The analysis of the obtained fuel was conducted at the Tubitak Marmara Research Centre. When the report was evaluated and compared with international standards, consistent results were obtained. It can be predicted that sustainable fuels can replace fossil fuels in the future.
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5

Díaz-Pérez, Manuel Antonio, and Juan Carlos Serrano-Ruiz. "Catalytic Production of Jet Fuels from Biomass." Molecules 25, no. 4 (February 12, 2020): 802. http://dx.doi.org/10.3390/molecules25040802.

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Анотація:
Concerns about depleting fossil fuels and global warming effects are pushing our society to search for new renewable sources of energy with the potential to substitute coal, natural gas, and petroleum. In this sense, biomass, the only renewable source of carbon available on Earth, is the perfect replacement for petroleum in producing renewable fuels. The aviation sector is responsible for a significant fraction of greenhouse gas emissions, and two billion barrels of petroleum are being consumed annually to produce the jet fuels required to transport people and goods around the world. Governments are pushing directives to replace fossil fuel-derived jet fuels with those derived from biomass. The present mini review is aimed to summarize the main technologies available today for converting biomass into liquid hydrocarbon fuels with a molecular weight and structure suitable for being used as aviation fuels. Particular emphasis will be placed on those routes involving heterogeneous catalysts.
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6

Ericsson, Karin. "Potential for the Integrated Production of Biojet Fuel in Swedish Plant Infrastructures." Energies 14, no. 20 (October 12, 2021): 6531. http://dx.doi.org/10.3390/en14206531.

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Анотація:
Replacing fossil jet fuel with biojet fuel is an important step towards reducing greenhouse gas (GHG) emissions from aviation. To this end, Sweden has adopted a GHG mandate on jet fuel, complementing those on petrol and diesel. The GHG mandate on jet fuel requires a gradual reduction in the fuel’s GHG emissions to up to 27% by 2030. This paper estimates the potential production of biojet fuel in Sweden for six integrated production pathways and analyzes what they entail with regard to net biomass input and the amount of hydrogen required for upgrading to fuel quality. Integrated production of biofuel intermediates from forestry residues and by-products at combined heat and power plants as well as at the forest industry, followed by upgrading to biojet fuel and other transportation fuels at a petroleum refinery, was assumed in all the pathways. The potential output of bio-based transportation fuels was estimated to 90 PJ/y, including 22 PJ/y of biojet fuel. The results indicate that it will be possible to meet the Swedish GHG mandate for jet fuel for 2030, although it will be difficult to simultaneously achieve the GHG mandates for road transportation fuels. This highlights the importance of pursuing complementary strategies for bio-based fuels.
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7

Boymans, Evert, Tom Nijbacker, Dennis Slort, Sander Grootjes, and Berend Vreugdenhil. "Jet Fuel Synthesis from Syngas Using Bifunctional Cobalt-Based Catalysts." Catalysts 12, no. 3 (March 3, 2022): 288. http://dx.doi.org/10.3390/catal12030288.

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Анотація:
Advanced biofuels are required to facilitate the energy transition away from fossil fuels and lower the accompanied CO2 emissions. Particularly, jet fuel needs a renewable substitute, for which novel production routes and technology are needed that are more efficient and economically viable. The direct conversion of bio-syngas into fuel is one such development that could improve the efficiency of biomass for jet fuel processes. In this work, bifunctional catalysts based on hierarchical zeolites are prepared, tested and evaluated for their potential use in the production of actual jet fuel. The bifunctional catalysts Co/H-mesoZSM-5, Co/H-mesoBETA and Co/H-mesoY have been applied, and their performance is compared with their microporous zeolite-based counterparts and two conventional Fischer–Tropsch Co catalysts. Co/H-mesoZSM-5 and Co/H-mesoBETA showed great potential for the direct production of jet fuel as bifunctional catalysts. Besides the high jet fuel yields under Fischer–Tropsch synthesis conditions at, respectively, 30.4% and 41.0%, the product also contained the high branched/linear hydrocarbon ratio desired to reach jet fuel specifications. This reveals the great potential for the direct conversion of syngas into jet fuel using catalysts that can be prepared in few steps from commercially available materials.
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8

Azam, Qummare, Ahmed Mahjub Alhaj, Mohd Shukur Zainol Abidin, Siti Zubaidah Sulaiman, and Nurul Musfirah Mazlan. "AN OUTLINE OF ALTERNATIVE AVIATION FUELS FROM SUSTAINABLE RESOURCES." Jurnal Teknologi 85, no. 1 (December 2, 2022): 11–19. http://dx.doi.org/10.11113/jurnalteknologi.v85.14563.

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Анотація:
The depletion of fossil fuels and their market inequality have led to the popularity of biofuels. Biofuels are a renewable energy source which can be a promising solution to the environmental issues created by fossil fuels. The emission of greenhouse gases and fluctuating prices of fossil fuels have put pressure on developing countries and small economic nations. Thus, one of the main concerns is the production of bio jet fuel from renewable resources, with a relatively low greenhouse gas life cycle and sustainability with affordable prices. Therefore, it is imperative to introduce and produce alternative aviation fuels generated from sustainable resources, specifically biofuels. In this study, we have reviewed alternative aviation fuels and their sources. We have also outlined the selection criteria for alternative aviation fuels along with discussing the sources that can be potentially used as fuel for the aviation industry.
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9

He, Haozhou. "Current Status of Jet Engines and Their Future on Fuel Efficiency." Highlights in Science, Engineering and Technology 53 (June 30, 2023): 18–25. http://dx.doi.org/10.54097/hset.v53i.9676.

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Анотація:
Recently, regulations on emissions for international aviation has become increasingly strict. In addition, cost of fossil fuel has increased owing to limited non-renewable resource. Therefore, it is important to understand fuel efficiency because this is a practical method to reduce the cost and emissions based on recent technology. In this article, theoretical background of jet engines will be demonstrated, which include structure of jet engines and cycle efficiency. Followed by factors that affect the efficiency of jet engines. Finally, applications of jet engines based on efficiency and methods that improve efficiency are demonstrated, which includes recent technologies and possible future directions.
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10

Jiménez-Islas, Donaji, Miriam E. Pérez-Romero, María de la Cruz Del Río-Rama, and Martha B. Flores-Romero. "Mapping Research Trends in Publications Related to Bio-Jet Fuel: A Scientometric Review." International Journal of Design & Nature and Ecodynamics 17, no. 1 (February 28, 2022): 1–8. http://dx.doi.org/10.18280/ijdne.170101.

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Анотація:
It is a fact that society has increased the need for mobility throughout the world. In that regard, it has become aware of the problems associated with the use of fossil fuels such as jet-fuel. As alter-natives, the use of bio-jet fuel has been proposed, which is a biofuel that researchers have evaluated and developed as an environmentally friendly alternative. The development of research on the topic of biofuels has generated a growing number of alternatives in the methods, technologies and raw materials for the production of bio-jet fuel. In this work, a bibliometric study has been developed to analyze the evolution of publications, the contribution of authors, countries, in terms of citation productivity on the topic of bio-jet fuel. Scientific publications were searched in the Scopus database for the period 2001 to 2021. The results showed that the publications have grown exponentially in the last 10 years. The most influential institution and country are from China. “Renewable and Sustainable Energy Reviews” is the most cited journal in the field of bio-jet fuel. The growth rate of publications was estimated using the Gompertz model, the rate was 0.2232 y-1. Most of the documents were published in journals Q1.
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11

El-Maghraby, Rehab M. "A Study on Bio-Diesel and Jet Fuel Blending for the Production of Renewable Aviation Fuel." Materials Science Forum 1008 (August 2020): 231–44. http://dx.doi.org/10.4028/www.scientific.net/msf.1008.231.

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Анотація:
Aviation industry is considered one of the contributors to atmospheric CO2emissions. It is forced to cut off carbon dioxide emission starting 2020. Current trends in bio-jet production involve mega projects with million dollars of investments. In this study, bio-jet fuel production by blending bio-diesel with traditional jet fuel at different concentrations of bio-diesel (5, 10, 15, 20 vol. %) was investigated. This blending technique will reduce bio-jet production cost compared to other bio-jet techniques. Bio-diesel was originally produced by the transesterification of non-edible vegetable oil (renewable sources), so, its blend with jet fuel will has a reduced carbon foot print. The blend was tested to ensure that the end product will meet the ASTM D1655 international specifications for Jet A-1 and Jet A and can be used in aircrafts.Available data on biodiesel blending with jet fuel in the literature is not consistent, there are many contradictory results. Hence, more investigations are required using locally available feedstocks. The main physicochemical properties for Jet A-1 and Jet A according to ASTM D1655 were tested to check if the blend will be compatible with existing turbojet engine systems. Different tests were conducted; vacuum distillation, smoke point, kinematic viscosity, density, flash point, total acidity and freezing point. In addition, heating value of the blend was calculated. The result was then compared with calculated value using blending indices available in the literature. Blending indices were able to predict the laboratory measured specifications for the studied blends.It was found that only 5% bio-diesel- 95% jet fuel blend (B5) meets ASTM standard for Jet A. Hence, biodiesel can be safely used as a blend with fossil-based jet for a concentration of up to 5% without any change in the ASTM specifications. Freezing point is the most important constrain for this blending technique. Higher blends of biodiesel will cause the bio-jet blend to fail ASTM specifications. In general, blending technique will reduce the cost impact that may have been incurred due to change in infrastructure when using other production techniques.
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12

Monteiro, Rodolpho R. C., Isabela A. dos Santos, Maria R. A. Arcanjo, Célio L. Cavalcante, Francisco M. T. de Luna, Roberto Fernandez-Lafuente, and Rodrigo S. Vieira. "Production of Jet Biofuels by Catalytic Hydroprocessing of Esters and Fatty Acids: A Review." Catalysts 12, no. 2 (February 20, 2022): 237. http://dx.doi.org/10.3390/catal12020237.

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Анотація:
The transition from fossil to bio-based fuels is a requisite for reducing CO2 emissions in the aviation sector. Jet biofuels are alternative aviation fuels with similar chemical composition and performance of fossil jet fuels. In this context, the Hydroprocessing of Esters and Fatty Acids (HEFA) presents the most consolidated pathway for producing jet biofuels. The process for converting esters and/or fatty acids into hydrocarbons may involve hydrodeoxygenation, hydrocracking and hydroisomerization, depending on the chemical composition of the selected feedstock and the desired fuel properties. Furthermore, the HEFA process is usually performed under high H2 pressures and temperatures, with reactions mediated by a heterogeneous catalyst. In this framework, supported noble metals have been preferably employed in the HEFA process; however, some efforts were reported to utilize non-noble metals, achieving a similar performance of noble metals. Besides the metallic site, the acidic site of the catalyst is crucial for product selectivity. Bifunctional catalysts have been employed for the complete process of jet biofuel production with standardized properties, with a special remark for using zeolites as support. The proper design of heterogeneous catalysts may also reduce the consumption of hydrogen. Finally, the potential of enzymes as catalysts for intermediate products of the HEFA pathway is highlighted.
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13

McGinnis, Rob. "CO2-to-Fuels Renewable Gasoline and Jet Fuel Can Soon Be Price Competitive with Fossil Fuels." Joule 4, no. 3 (March 2020): 509–11. http://dx.doi.org/10.1016/j.joule.2020.01.002.

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14

Peters, Morenike Ajike, Carine Tondo Alves, and Jude Azubuike Onwudili. "A Review of Current and Emerging Production Technologies for Biomass-Derived Sustainable Aviation Fuels." Energies 16, no. 16 (August 21, 2023): 6100. http://dx.doi.org/10.3390/en16166100.

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Анотація:
The aviation industry is a significant contributor to global carbon dioxide emissions, with over 920 million tonnes per year, and there is a growing need to reduce its environmental impact. The production of biojet fuel from renewable biomass feedstocks presents a promising solution to address this challenge, with the potential to reduce greenhouse gas emissions and dependence on fossil fuels in the aviation sector. This review provides an in-depth discussion of current and emerging biojet fuel conversion technologies, their feasibility, and their sustainability, focusing on the promising conversion pathways: lipids-to-jet, sugar-to-jet, gas-to-jet, alcohol-to-jet, and whole biomass-to-jet. Each technology is discussed in terms of its associated feedstocks, important chemistries, and processing steps, with focus on recent innovations to improve yields of biojet product at the required specifications. In addition, the emerging power-to-liquid technology is briefly introduced. With the integrated biorefinery approach, consideration is given to biomass pretreatment to obtain specific feedstocks for the specific technology to obtain the final product, with the embedded environmental sustainability requirements. In addition, the review highlights the challenges associated with the biojet production technologies, with embedded suggestions of future research directions to advance the development of this important and fast-growing sustainable fuel industry.
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15

Deuber, Raquel de Souza, Jéssica Marcon Bressanin, Daniel Santos Fernandes, Henrique Real Guimarães, Mateus Ferreira Chagas, Antonio Bonomi, Leonardo Vasconcelos Fregolente, and Marcos Djun Barbosa Watanabe. "Production of Sustainable Aviation Fuels from Lignocellulosic Residues in Brazil through Hydrothermal Liquefaction: Techno-Economic and Environmental Assessments." Energies 16, no. 6 (March 15, 2023): 2723. http://dx.doi.org/10.3390/en16062723.

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Анотація:
Decarbonization of the aviation sector relies on deployment of sustainable aviation fuels (SAF) at commercial scale. Hydrothermal liquefaction (HTL) has been recognized as a promising technology to help supply the increasing projected SAF demand. High availability of agro-industrial residues, combined with a well-established biorefinery system, makes the sugarcane industry in Brazil a good option for HTL technology deployment. Moreover, challenges regarding the economic feasibility of SAF from HTL could be partially addressed by the RenovaBio policy, a market-driven incentive mechanism of carbon credits implemented in Brazil. This study investigated both the techno-economic and life cycle assessment of SAF production from sugarcane lignocellulosic residues, considering HTL integrated to a first-generation ethanol distillery and a HTL stand-alone facility. The evaluated scenarios showed great climate mitigation potential, reaching a reduction of up to 73–82% when compared to fossil jet fuel. The minimum fuel selling price of SAF at 15.4 USD/GJ indicated potential of economic competitiveness with fossil jet fuel in the best integrated scenario. The economic benefits obtained from carbon credits are not enough to enable feasibility of HTL in the stand-alone scenarios, even with the avoidance of carbon prices projected at 125 USD/tonne CO2-eq.
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16

Gao, Yujue. "Sustainable aviation fuel as a pathway to mitigate global warming in the aviation industry." Theoretical and Natural Science 26, no. 1 (December 20, 2023): 60–67. http://dx.doi.org/10.54254/2753-8818/26/20241015.

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Анотація:
The extensive utilization of fossil fuels by humanity has led to notable ecological degradation alongside a surge in productivity. The ensuing climate change, a result of global warming, poses a grave threat to human survival. A significant contributor to global warming is the emission of abundant greenhouse gases, with carbon dioxide being the most prevalent. Addressing global warming necessitates the identification and adoption of cleaner, alternative fuels to diminish carbon dioxide emissions. Sustainable Aviation Fuel (SAF) emerges as a prime alternative in this context. Chemically akin to conventional and fossil fuels, SAF originates from cleaner sources, offering a reduction in carbon dioxide emissions upon combustion. This paper highlights the importance of SAF as a viable strategy to mitigate CO2 emissions resulting from fossil fuel combustion. The paper also examines different SAF synthesis approaches, such as Fischer-Tropsch, Hydrogenated fatty acid esters and fatty acids (HEFA), and Alcohol-to-Jet (ATJ) processes. In summary, challenges such as high production costs, raw material price fluctuations, and the need for supportive policies hinder SAF's widespread adoption. To address climate change and reduce aviation emissions, further research, technological advancements, government incentives, and collaborative efforts within the aviation industry are crucial.
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17

Huq, Nabila A., Glenn R. Hafenstine, Xiangchen Huo, Hannah Nguyen, Stephen M. Tifft, Davis R. Conklin, Daniela Stück, et al. "Toward net-zero sustainable aviation fuel with wet waste–derived volatile fatty acids." Proceedings of the National Academy of Sciences 118, no. 13 (March 15, 2021): e2023008118. http://dx.doi.org/10.1073/pnas.2023008118.

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Анотація:
With the increasing demand for net-zero sustainable aviation fuels (SAF), new conversion technologies are needed to process waste feedstocks and meet carbon reduction and cost targets. Wet waste is a low-cost, prevalent feedstock with the energy potential to displace over 20% of US jet fuel consumption; however, its complexity and high moisture typically relegates its use to methane production from anaerobic digestion. To overcome this, methanogenesis can be arrested during fermentation to instead produce C2 to C8 volatile fatty acids (VFA) for catalytic upgrading to SAF. Here, we evaluate the catalytic conversion of food waste–derived VFAs to produce n-paraffin SAF for near-term use as a 10 vol% blend for ASTM “Fast Track” qualification and produce a highly branched, isoparaffin VFA-SAF to increase the renewable blend limit. VFA ketonization models assessed the carbon chain length distributions suitable for each VFA-SAF conversion pathway, and food waste–derived VFA ketonization was demonstrated for >100 h of time on stream at approximately theoretical yield. Fuel property blending models and experimental testing determined normal paraffin VFA-SAF meets 10 vol% fuel specifications for “Fast Track.” Synergistic blending with isoparaffin VFA-SAF increased the blend limit to 70 vol% by addressing flashpoint and viscosity constraints, with sooting 34% lower than fossil jet. Techno-economic analysis evaluated the major catalytic process cost-drivers, determining the minimum fuel selling price as a function of VFA production costs. Life cycle analysis determined that if food waste is diverted from landfills to avoid methane emissions, VFA-SAF could enable up to 165% reduction in greenhouse gas emissions relative to fossil jet.
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18

Micheli, Matteo, Daniel Moore, Vanessa Bach, and Matthias Finkbeiner. "Life-Cycle Assessment of Power-to-Liquid Kerosene Produced from Renewable Electricity and CO2 from Direct Air Capture in Germany." Sustainability 14, no. 17 (August 26, 2022): 10658. http://dx.doi.org/10.3390/su141710658.

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Анотація:
Decarbonization of the aviation sector is crucial to reaching the global climate targets. We quantified the environmental impacts of Power-to-Liquid kerosene produced via Fischer-Tropsch Synthesis from electricity and carbon dioxide from air as one broadly discussed alternative liquid jet fuel. We applied a life-cycle assessment considering a well-to-wake boundary for five impact categories including climate change and two inventory indicators. Three different electricity production mixes and four different kerosene production pathways in Germany were analyzed, including two Direct Air Capture technologies, and compared to fossil jet fuel. The environmental impacts of Power-to-Liquid kerosene varied significantly across the production pathways. E.g., when electricity from wind power was used, the reduction in CO2-eq. compared to fossil jet fuel varied between 27.6–46.2% (with non-CO2 effects) and between 52.6–88.9% (without non-CO2 effects). The reduction potential regarding CO2-eq. of the layout using low-temperature electrolysis and high-temperature Direct Air Capture was lower compared to the high-temperature electrolysis and low-temperature Direct Air Capture. Overall, the layout causing the lowest environmental impacts uses high-temperature electrolysis, low-temperature Direct Air Capture and electricity from wind power. This paper showed that PtL-kerosene produced with renewable energy could play an important role in decarbonizing the aviation sector.
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19

Gitan, Ali Ahmed, Rozli Zulkifli, Kamaruzaman Sopian, and Shahrir Abdullah. "Twin Pulsating Jets Impingement Heat Transfer for Fuel Preheating in Automotives." Applied Mechanics and Materials 663 (October 2014): 322–28. http://dx.doi.org/10.4028/www.scientific.net/amm.663.322.

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Анотація:
The problem of environmental pollution and depletion of fossil fuel can be reduced in automotives by using an alternative bio-fuel and improve the ignition process in engine. Both solutions need to use the fuel preheating technique. This work presents the idea of fuel preheating by using exhaust impingement on the fuel tank. Heat transfer between twin pulsating hot air jets and flat copper target was investigated as an application for preheating of automotive fuel to improve ignition process in the engine. The nozzle of 20 mm was used to produce air jet of Reynolds number, Re ≃ 5500 and a temperature of 54°C. The impinged target was imposed to still air surrounding at temperature of 24°C. Pulsating frequencies of 10-50 Hz were applied on air jets by using twin pulsating jet mechanism. The effect of pulsation frequency on heat transfer was measured using IR camera and heat flux-temperature micro foil sensor. The results obtained by both of these methods showed well agreement. Also, the results revealed significant influence of flow rate difference between steady and pulsating jet cases. In addition, the highest Nusselt number, Nu ≃ 7.2, was obtained at pulsation frequency of 20 Hz.
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20

Talero, Gabriel, Camilo Bayona-Roa, Giovanny Muñoz, Miguel Galindo, Vladimir Silva, Juan Pava, and Mauricio Lopez. "Experimental Methodology and Facility for the J69-Engine Performance and Emissions Evaluation Using Jet A1 and Biodiesel Blends." Energies 12, no. 23 (November 28, 2019): 4530. http://dx.doi.org/10.3390/en12234530.

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Анотація:
Aeronautic transport is a leading energy consumer that strongly contributes to greenhouse gas emissions due to a significant dependency on fossil fuels. Biodiesel, a substitution of conventional fuels, is considered as an alternative fuel for aircrafts and power generation turbine engines. Unfortunately, experimentation has been mostly limited to small scale turbines, and technical challenges remain open regarding operational safety. The current study presents the facility, the instrumentation, and the measured results of experimental tests in a 640 kW full-scale J69-T-25A turbojet engine, operating with blends of Jet A1 and oil palm biodiesel with volume contents from 0% to 10% at different load regimes. Findings are related to the fuel injection system, the engine thrust, and the emissions. The thrust force and the exhaust gas temperature do not expose a significant variation in all the operation regimes with the utilization of up to 10% volume content of biodiesel. A maximum increase of 36% in fuel consumption and 11% in injection pressure are observed at idle operation between B0 and B10. A reduction of the CO and HC emissions is also registered with a maximum variation at the cruise regime (80% Revolutions Per Minute—RPM).
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21

Ghahremani, Amirreza, Mohammad Ahari, Mojtaba Jafari, Mohammad Saidi, Ahmad Hajinezhad, and Ali Mozaffari. "Experimental and theoretical study on spray behaviors of modified bio-ethanol fuel employing direct injection system." Thermal Science 21, no. 1 Part B (2017): 475–88. http://dx.doi.org/10.2298/tsci160108253g.

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Анотація:
One of the key solutions to improve engine performance and reduce exhaust emissions of internal combustion engines is direct injection of bio-fuels. A new modified bio-ethanol is produced to be substituted by fossil fuels in gasoline direct injection engines. The key advantages of modified bio-ethanol fuel as an alternative fuel are higher octane number and oxygen content, a long-chain hydro-carbon fuel, and lower emissions compared to fossil fuels. In the present study spray properties of a modified bio-ethanol and its atomization behaviors have been studied experimentally and theoretically. Based on atomization physics of droplets dimensional analysis has been performed to develop a new non-dimensional number namely atomization index. This number determines the atomization level of the spray. Applying quasi-steady jet theory, air entrainment and fuel-air mixing studies have been performed. The spray atomization behaviors such as atomization index number, Ohnesorge number, and Sauter mean diameter have been investigated employing atomization model. The influences of injection and ambient conditions on spray properties of different blends of modified bio-ethanol and gasoline fuels have been investigated performing high-speed visualization technique. Results indicate that decreasing the difference of injection and ambient pressures increases spray cone angle and projected area, and decreases spray tip penetration length. As expected, increasing injection pressure improves atomization behaviors of the spray. Increasing percentage of modified bio-ethanol in the blend, increases spray tip penetration and decreases the projected area as well.
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22

Gunasekar, P., S. Manigandan, Venkatesh S., R. Gokulnath, Rakesh Vimal, and P. Boomadevi. "Effect of hydrogen addition on exergetic performance of gas turbine engine." Aircraft Engineering and Aerospace Technology 92, no. 2 (October 26, 2019): 180–85. http://dx.doi.org/10.1108/aeat-05-2019-0095.

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Purpose The depletion of fossil fuel and emissions of harmful gases forced the pioneers in search of alternate energy source. The purpose of this study is to present an effective use of hydrogen fuel for turbojet engines based on its exergetic performance. Design/methodology/approach This study was performed to measure the assessment of exergetic data of turbojet engines. Initially, the test was carried out on the Jet A-1 fuel. Then, a series of similar tests were carried out on turbojet engines with hydrogen fuel to measure their performance results. Finally, the exergetic values of both were compared with each other. Findings The introduction of hydrogen fuel reduced the exergy efficiency, and a 10 per cent reduction was observed in exergy efficiency. Simultaneously, the waste exergy rate increased by 9 per cent. However, because of the high specific fuel exergy, hydrogen fuel was better than Jet A-1 fuel. Note that parameters such as environmental effect factor and ecological effect witnessed an increase in their index owing to the addition of hydrogen. Practical implications Introduction of alternative blends is necessary for achieving lower emission of gases such as CO, NOx and CO2 from gas turbine engines without compromising on performance. The Jet A fuels were replaced by blends to obtain better emission characteristics. Originality/value The use of hydrogen in turbojet engines showed an adverse effect on exergetic performance. However, it was very impressive to see a 200 per cent reduction in emissions. From the comparison of exergy efficiency results of inlet, combustion and nozzle, it is evident that the combustion chamber has the largest values of exergy ratio, waste exergy ratio, cost flow, ecological factor, environmental factor and fuel ratio owing to irreversibility in the combustion process.
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23

Niszczota, Paweł, and Marian Gieras. "Influence of surfactant addition to emulsion fuels on the hot section of turbine engines." Journal of Konbin 53, no. 4 (December 28, 2023): 13–26. http://dx.doi.org/10.5604/01.3001.0054.1752.

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Анотація:
Due to the growing awareness of ecological threats, more and more attention is paid to the emission problem of undesirable substances into the atmosphere, the source of which is transport and energy. The impact of these factors on the environment can be reduced by using alternative fuels, which are non-fossil fuels, or by modifying these fuels to ensure lower emissions. One of the methods for reducing emissions from engines is the use of water fuel emulsion as fuel, which has a particularly positive effect on the emission of nitrogen oxides at high loads of drive and power units. An important issue affecting the possibility of using this fuel type is the impact of their use on the elements of the units in contact with fuel containing water and, optionally, an emulsifier. This paper presents inspection results of the hot section of a miniature gas turbine powered by Jet-A1 aviation fuel with the emulsifier addition. On the basis of these observations, the components of emulsion fuels were determined, which are the cause of the characteristic deposits occurring on the hot sections of the units after using emulsion fuels.
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24

Mazlan, Nurul Musfirah, Mark Savill, and Timos Kipouros. "Evaluating NOx and CO emissions of bio-SPK fuel using a simplified engine combustion model: A preliminary study towards sustainable environment." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 5 (April 19, 2016): 859–65. http://dx.doi.org/10.1177/0954410016643980.

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Awareness of environmental and economic issues associated with fossil fuel has led to the exploration of alternative fuels for aviation. Analysis and measurements of alternative fuel using real aircraft engines are complex and costly. Thus, evaluation only through computation is an option at present. This paper presents an analysis of aircraft engine emissions, particularly NOx and CO, from the blend of bio-synthetic paraffinic kerosene (bio-SPK) fuel with kerosene using a simplified gas emission model. Three different fuels, namely, a conventional aviation fuel Jet-A, Jatropha bio-SPK and Camelina bio-SPK were tested as pure and as blends with Jet-A. Chemical properties of the tested fuels were introduced into HEPHAESTUS, an in-house gas emission software developed in Cranfield University. HEPHAESTUS was developed based on the physics-based approach by incorporating a number of stirred reactors to predict NOx, CO, UHC and soot. Gaseous emissions generated from kerosene were observed to follow the trends provided by the ICAO databank. The capability of HEPHAESTUS in predicting the NOx and CO level from biofuel is yet to be explored. The level of NOx and CO predicted in this study followed the trends shown in the literature, although they quantitatively differed. Compared to Jet-A, NOx decreased and CO increased as the percentage of Jatropha bio-SPK and Camelina bio-SPK in the mixture increased. NOx reduction was consistent with the reduction in flame temperature because NOx generation considered in the model was dominantly based on thermal NOx. In contrast, increases in CO were due to low flame temperature that led to incomplete combustion. The consistency of the results obtained showed that the computational work performed in this study as an initial step toward the prediction of emission level of biofuels was successful. However, further studies on the experimental work or computational fluid dynamic simulation is essential.
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25

Jeon, Bo-il, Shinji Kim, Yeo Song Yoon, and Seungho Jung. "Quantitative Risk Assessment of Hydrogen Refueling Station in Cheonan City of South Korea." Energies 16, no. 20 (October 18, 2023): 7138. http://dx.doi.org/10.3390/en16207138.

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The average temperature of the Earth has risen due to the accumulation of greenhouse gases emitted from the usage of fossil fuels. The consequential climate changes have caused various problems, fueling the growing demand for environmentally friendly energy sources that can replace fossil fuels. Batteries and hydrogen have thus been utilized as substitute energy sources for automobiles to reduce fossil fuel consumption. Consequently, the number of hydrogen refueling stations is increasing due to an increase in the number of hydrogen-powered vehicles. However, several incidents have been reported in the United States of America and Japan where hydrogen refueling stations have been operating for a long time. A risk assessment of hydrogen refueling stations operating in urban areas was performed in this study by calculating the risk effect range using a process hazard analysis tool (PHAST) v8.7 from DNV-GL and a hydrogen risk assessment model (HyRAM) from Sandia National Laboratories (SNL). The societal risk was assessed through a probit model based on the calculation results. The assessment results showed that the risk caused by jet fire and overpressure in an incident is lower than the ‘as low as reasonably practicable’ (ALARP) level.
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26

Pawlak, Małgorzata, and Michał Kuźniar. "The Effects of the Use of Algae and Jatropha Biofuels on Aircraft Engine Exhaust Emissions in Cruise Phase." Sustainability 14, no. 11 (May 25, 2022): 6488. http://dx.doi.org/10.3390/su14116488.

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Due to environmental pressure and the prevailing political and economic situation in the world, alternatives to traditional fossil fuels are being sought. The use of bio-derived fuels may reduce the emission of pollutants present in jet engine exhausts. The presented research investigates the possibility of replacing the conventional fuel, which is kerosene, with plant-derived fuels from marine algae and jatropha. During the analysis, based on the available data, the emission indices of pollutants were computed, and then, for the adopted aircraft and route, the emissions for kerosene and alternative fuels were determined. A significant reduction in the emission of most analyzed compounds (even by 40% for CO) was achieved compared to the emission for kerosene. The obtained results are discussed in the conclusion section.
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27

Bauen, Ausilio, Anisha Harris, Christopher Sim, Nick Gudde, Matteo Prussi, and Nicolae Scarlat. "CORSIA Lower Carbon Aviation Fuels: An Assessment of the Greenhouse Gas Emission Reduction Potential." Applied Sciences 12, no. 22 (November 21, 2022): 11818. http://dx.doi.org/10.3390/app122211818.

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Curbing aviation emissions is clear goal for the aviation sector, but it is a challenging task. At international level, the ICAO CORSIA initiative promotes the use of alternative fuels as a means to decarbonise flights. Among alternative fuels, lower carbon aviation fuels (LCAF) have been proposed under CORSIA. LCAF refers to a fossil fuel, which have been produced in a way that results in at least 10% lower lifecycle GHG emissions compared to a benchmark value. This paper analyses potential LCAF solutions for reducing GHG emissions of kerosene production and evaluates them relative to the ICAO baseline of 89.0 gCO2eq/MJ of fuel. The study analyses the levers that can reduce GHG upstream emissions (emissions from crude oil production) and refining emissions as well. This study shows that no one lever can reduce emissions to a sufficient level to meet the requirement of being a CORSIA-eligible fuel, and therefore that the deployment of multiple levers needed. Since jet fuel comprises only around 10% of total refining output, the LCAF measures could support the implementation of large, high-abatement cost changes, such as refinery-wide carbon capture and storage that affects multiple fuels.
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28

Detsios, Nikolaos, Stella Theodoraki, Leda Maragoudaki, Konstantinos Atsonios, Panagiotis Grammelis, and Nikolaos G. Orfanoudakis. "Recent Advances on Alternative Aviation Fuels/Pathways: A Critical Review." Energies 16, no. 4 (February 14, 2023): 1904. http://dx.doi.org/10.3390/en16041904.

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The Paris Agreement’s objectives related to climate change put aviation under great pressure and environmental inspection. In particular, the aviation industry is committed to achieving a 50% reduction in CO2 emissions by 2050 compared to 2005 levels. A shift to alternative aviation fuels seems imperative. The International Air Transport Association (IATA) has identified the production of drop-in sustainable liquid fuels (SAFs) as the most promising strategy, at least short term, to reduce the environmental impact of the sector. Within this review, a critical summary of the current alternative aviation fuels/pathways is presented and a comparative analysis of the dominant technologies is performed considering techno-economic assessment, environmental evaluation, and future projections. The impact of the ‘ReFuelEU Aviation’ initiative on the current dominant policies and market incentives is assessed. Hydroprocessed esters and fatty acids (HEFA), Fischer–Tropsch (FT) synthesis, alcohol-to-jet (AtJ) conversion, and e-fuel pathways are put under the microscope. A wide range of potential fuel selling prices (0.81–5.00 EUR/L) was observed due to the presence of multiple routes, while some pathways seem able to secure more than 90% emission savings compared to the fossil jet reference. The accelerated scale-up of SAF production is a reasonable demand for the aviation industry. The establishment of a sustainable scale-up framework and the alignment of all of the involved aviation stakeholders is an immediate challenge.
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29

Wiebe, Wilhelm, Thomas v. Unwerth, and Sven Schmitz. "Hydrogen pump for hydrogen recirculation in fuel cell vehicles." E3S Web of Conferences 155 (2020): 01001. http://dx.doi.org/10.1051/e3sconf/202015501001.

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A promising alternative to fossil-fuelled vehicles are battery-powered vehicles and fuel cell (FC) vehicles. The major differences between fuel cell and battery-powered vehicles are the range and refuelling times of each vehicle type. With a hydrogen (Hed vehicles are the range and refuelling times of each vehicle type. With a hydrogen (H2) fuelling time of approx. 5 minutes it is possible to cover a distance of up to 800 km with a fuel cell vehicle. These properties make a fuel cell vehicle comparable to a fossil fuel powered vehicle. Furthermore, due to short fuelling times and long range capabilities, fuel cell vehicles are more suitable for long-distance, trucking and agriculture than battery-powered vehicles. The aim of current research is to increase the profitability of fuel cells by reducing costs and improving performance. To ensure a high performance of the fuel cell stack, more hydrogen is supplied to the stack than is needed for the reaction. Therefore, unused hydrogen is pumped back to the anode inlet of the FC-stack using a jet pump or a recirculation blower. In this study, the application of an electrochemical compressor or hydrogen pump (HP) for hydrogen recirculation is suggested. The hydrogen pump is an innovative H2 transport technology with the additional functions of compression and purification in the recirculation system. Hydrogen pumps are very efficient compared to mechanical compressors due to the almost isothermal conditions they operate under. Furthermore, due to the modular design, hydrogen compressors can utilize a minimal amount of space in vehicles.
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30

Liu, Aiguo, Ruiyang Fan, Qiaochu Liu, Lei Xi, and Wen Zeng. "Numerical and Experimental Study on Combustion Characteristics of Micro-Gas Turbine Biogas Combustor." Energies 15, no. 21 (November 7, 2022): 8302. http://dx.doi.org/10.3390/en15218302.

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The use of biogas in land-based gas turbines for power generation is a promising approach to reducing greenhouse gases and our dependence on fossil fuels. The focus of this research was to investigate the fuel/air mixing and combustion performance in an DLE (dry low emission) type can combustor designed for a micro-gas turbine. The fuel and air mixing uniformity was studied considering the air flow characteristic and fuel injection performance through the numerical simulation. The influence of the fuel/air mixing characteristics on the combustion characteristics was studied by numerical simulation and experimental tests. The combustion characteristics studied included the temperature field in the combustor, the pattern factor at the combustor outlet, combustion efficiency, and pollutant emission characteristics. The results show the position of the fuel nozzle has little effect on the mixing uniformity due to the limited mixing space for the micro-gas turbine combustor, while there are optimal fuel nozzle diameters to generate the suitable fuel jet momentum for the mixing process. The fuel/air mixing characteristics had an obvious influence on the combustion performance for the studied DLE combustor. The increase in the fuel air mixing uniformity can decrease the NOx emissions and generate a better temperature distribution at the combustor outlet. The increased mixing uniformity may decrease the combustion efficiency and increase the CO emissions of the micro-gas turbine combustor.
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31

Sharma, Vikas, Abul Kalam Hossain, Ganesh Duraisamy, and Gareth Griffiths. "Microalgal Biodiesel: A Challenging Route toward a Sustainable Aviation Fuel." Fermentation 9, no. 10 (October 16, 2023): 907. http://dx.doi.org/10.3390/fermentation9100907.

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Анотація:
By 2050, aviation-related carbon emissions are expected to quadruple to over 3000 million tonnes of carbon dioxide, so finding sustainable alternative solutions to minimise pollution is a key scientific challenge. Aviation gasoline and kerosene are currently used to power most jet engines. While battery-powered planes and planes that could utilise a cleaner fuel, such as hydrogen, are possible, the time scale required to improve and implement these technologies is distant, with air fleet turnover taking some 30 years. Existing jet engines could be modified to run on biodiesel, and considering the close similarity in fuel density to kerosene, could be a less disruptive approach to the industry. The sheer volume of biodiesel required remains a challenge, and certainly, using plant-derived oils grown on arable land is not acceptable, as it competes with food production. However, high-lipid-yielding microalgae (where productivity is an order of magnitude greater than oilseeds), grown on marginal land, such as desert or semi-desert areas of the world, could be possible. Indeed, to replace 30% of fossil fuel with algal-derived biodiesel would require 11,345 km2 of land. Biodiesel preparation is well understood, but what is lacking is proven technology aimed at optimising microalgal production of oil at a much larger scale. Here, a synergic review of the current state-of-the-art in algal production, that includes strain selection, possible production sites, culturing costs, and harvesting to identify the bottlenecks in meeting the ASTM specifications for the aviation industry, is presented.
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32

Chiaramonti, David, Giacomo Talluri, George Vourliotakis, Lorenzo Testa, Matteo Prussi, and Nicolae Scarlat. "Can Lower Carbon Aviation Fuels (LCAF) Really Complement Sustainable Aviation Fuel (SAF) towards EU Aviation Decarbonization?" Energies 14, no. 19 (October 8, 2021): 6430. http://dx.doi.org/10.3390/en14196430.

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Анотація:
The present work provides an analysis of the potential impact of fossil-based Low Carbon Aviation Fuels (LCAF) for the European aviation sector, with a time horizon to 2050. LCAF are a crude-derived alternative to kerosene, offering some Green House Gas (GHG) savings, and have been defined by ICAO as eligible fuels for mitigating the environmental impact of aviation. A methodological framework to evaluate the EU technical potential for LCAF production is developed, based on data on crude utilization for jet fuel production in EU refineries, relevant carbon intensity reduction technologies, market prices, and aviation fuel volumes. Two different baselines for fossil-derived kerosene carbon intensity (CI) are considered: a global figure of 89 gCO2e/MJ and an EU-27-specific one of 93.1 gCO2eq/MJ. Three scenarios considering increasing levels of CI reduction are then defined, taking into account the current and potential commercial availability of some of the most relevant carbon intensity reduction technologies. The analysis demonstrates that, even if LCAF could offer GHG saving opportunities, their possible impact, especially when compared to the ambition level set in the most recent European legislative proposals, is very limited in most of the analysed scenarios, with the exception of the most ambitious ones. At 2030, a non-zero technical potential is projected only in the higher CI reduction scenario, ranging between 1.8% and 14.2% of LCAF market share in the EU-27 (equal to 0.6 to 4.75 Mtoe), depending on the considered Baseline for CI. At 2050, almost all considered scenarios project a larger technical potential, ranging between 6.9% and 22.2% for the global Baseline (2.21 to 7.13 Mtoe), and between 1.8% and 16.2% for the EU-27 Baseline (0.58 to 5.2 Mtoe). LCAF additional costs to current production costs are also discussed, given their relevance in large-scale deployment of these technologies, and are projected to range between 39 and 46.8 USD/toe.
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33

Mizher, Usama J., and Peter A. Velmisov. "Mathematical modeling of a swirling jet in applications to low-emission combustion of low-grade fuels." Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva 23, no. 3 (September 30, 2021): 308–17. http://dx.doi.org/10.15507/2079-6900.23.202103.308-317.

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Abstract. The search for new solutions in the field of energy, preventing negative impact on the environment, is one of the priority tasks for modern society. Natural gas occupies a stable position in the demand of the UES of Russia for fossil fuel. Biogas is a possible alternative fuel from organic waste. Biogas has an increased content of carbon dioxide, which affects the speed of flame propagation, and a lower content of methane, which reduces its heat of combustion. However, the combined combustion of natural gas and biogas, provided that the mixture of fuel and oxidizer is well mixed, can, on the one hand, reduce the maximum adiabatic temperature in the combustion chamber of power boilers at TPPs, and, on the other, increase the stability of biogas combustion. For the combined combustion of natural gas and biogas in operating power boilers, it is necessary to reconstruct the existing burners. For a high-quality reconstruction of burners capable of providing stable and low-toxic combustion of fuel, it is important to have theoretical data on the combustion effect of combustion of combinations of organic fuels on the temperature distribution in the combustion zone and on its maximum value. In this paper, self-similar solutions of the energy equation for axisymmetric motion of a liquid (gas) in a model of a viscous incompressible medium are obtained. Basing on them, a stationary temperature field in swirling jets is constructed. A set of programs based on the ANSYS Fluent software solver has been developed for modeling and researching of thermal and gas-dynamic processes in the combustion chamber. On the basis of the k - ϵ (realizable) turbulence model, the combustion process of a swirling fuel-air mixture is simulated. The results of an analytical and numerical study of the temperature and carbon dioxide distribution in the jet are presented.
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34

Mohanty, Ipsita, K. N. V. Sree Devi, and M. V. S. Murali Krishna. "Investigations on exhaust emissions of aninsulated diesel engine with alternative fuels." Ecology, Environment and Conservation 29, no. 01 (2023): 298–308. http://dx.doi.org/10.53550/eec.2023.v29i01.044.

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Анотація:
In the context of depletion of fossil fuels, ever increase of pollution levels with fossil fuels and escalating prices of crude petroleum in International market, the search for alternative fuels has become pertinent. Alcohols (ethanol, methanol and butanol) and vegetable oils are important substitutes for diesel fuel. Alcohols renewable in nature, have low C/H (C=Number of carbon atoms and H=Number of hydrogen atoms in fuel composition and highly volatile. Butanol has higher calorific value than ethanol and methanol. Vegetable oils comparable cetane number and energy content when compared to diesel fuel. However, the drawbacks of vegetable oils (high viscosity and low volatility) and alcohols (low cetane number and low energy content) to be used as fuels in diesel engine call for semi adiabatic diesel engine (SADE) with its significance characteristics of higher operating temperature, maximum heat release, high brake thermal efficiency and ability to handle the low calorific value fuel.Exhaust emissions from diesel engine cause severe health hazards once they are inhaled in. They also cause environmental disorders. Hence control of these emissions is immediate step and urgent. In order to take advantages from both vegetable oils and alcohols, it is proposed to use the vegetable oil along with carbureted butanol in semi adiabatic diesel engine. Butanol was inducted into the engine through a variable jet carburetor, installed at the inlet manifold of the engine at different percentages of crude vegetable oil at full load operation on mass basis. Crude vegetable oil was injected at near end of compression stroke in conventional manner. Exhaust emissions were determined with semi adiabatic engine consisting of air gap (3 mm) insulated piston with superni (an alloy of nickel) crown, air gap (3 mm) insulated liner with superni insert and ceramic coated cylinder head with mixture of carbureted butanol and crude vegetable oil with varied injector opening pressure and injection timing. Comparative studies were made with data of conventional engine (CE) with maximum induction of Butanol at similar operating conditions. Aldehydes were measured by wet method. The maximum induction of butanol was 60% at recommended injection timing of 27obTDC (before top dead center), while it was 55% at optimum injection timing of 29obTDC.
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35

Ribeiro, Daniela F. S., André R. R. Silva, and Miguel R. O. Panão. "Insights into Single Droplet Impact Models upon Liquid Films Using Alternative Fuels for Aero-Engines." Applied Sciences 10, no. 19 (September 25, 2020): 6698. http://dx.doi.org/10.3390/app10196698.

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Анотація:
In aero-engines, the introduction of biofuels is among the best alternatives to fossil fuels, and this change is likely to affect the impact of droplets on interposed surfaces. Under this framework, this work reviews the main morphological hydrodynamic structures occurring upon the impact of a liquid droplet on a wetted surface, using jet fuel and biofuel mixtures as alternative fuels. The experiments performed allow investigating the effect of the liquid film thickness on the dynamic behavior of single drop impact, considering the relevancy of these phenomena to the optimization of engine operating parameters. Particular emphasis is given to the occurrence of crown splash, and the morphological differences in the outcomes of drop impact depending on the impact conditions and fluid properties. The four fluids tested included pure water (as reference), 100% Jet A-1, 75%/25%, and 50%/50% mixtures of Jet A-1 and NExBTL (Neste Renewable Diesel)—with the Weber impact number between 103 and 1625; Reynolds values 1411–16,889; and dimensionless film thicknesses of δ = 0.1, 0.5, and 1. The analysis on the secondary atomization for the different fluids evidences the predominance of prompt and crown splash, and jetting for alternative fuels. Finally, besides a systematic review of empirical correlations for the transition to splash, we investigate their universality by extrapolating the validation range to evaluate their ability to predict the outcome of impact accurately. One of the correlations studied show the highest degree of universality for the current experimental conditions, despite its limitation to thin liquid films (δ=0.1).
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36

Frątczak, Jakub, Héctor de Paz Carmona, Zdeněk Tišler, José M. Hidalgo Herrador, and Zahra Gholami. "Hydrocracking of Heavy Fischer–Tropsch Wax Distillation Residues and Its Blends with Vacuum Gas Oil Using Phonolite-Based Catalysts." Molecules 26, no. 23 (November 26, 2021): 7172. http://dx.doi.org/10.3390/molecules26237172.

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Анотація:
The Fischer–Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher–Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.
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37

Raghu, P., Michael S. Mukilan, R. Bharath Viswanath, S. Audithya Krishna, and N. Nallusamy. "Experimental Study on the Spray Characteristics of Diesel and Biodiesel (Jatropha Oil) in a Spray Chamber." Advanced Materials Research 768 (September 2013): 180–87. http://dx.doi.org/10.4028/www.scientific.net/amr.768.180.

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Анотація:
The increasing industrialization and motorization of the world has led to a steep rise for the demand of petroleum-based fuels. Petroleum based fuels are obtained from limited reserves highly concentrated in certain regions of the world i.e. those countries that lack these resources are facing energy crisis. Hence it is necessary to look for alternative fuels which can be produced from resources available locally within the country such as biodiesel, alcohol and vegetable oil. The biodiesel is technically competitive with conventional petroleum derived diesel fuel and requires no changes in the fuel distribution system. For this reason and its biodegradability, use of biodiesel is considered a good alternative of fossil fuels. Injection process of biodiesel influences the atomization and dispersion of fuel in the combustion chamber. In this research work the influence of biodiesel on injection process and their impact on the air-fuel mixture preparation are studied. Spray characteristics of biodiesel (Jatropha oil) and diesel under various injection pressures were studied experimentally. Spray penetration and spray angle were measured in a spray vessel using a high speed video camera. The study shows the biodiesel gives longer spray tip penetration and spray angle are smaller than those of diesel fuels. The parameters like break up time and break up velocity were for biodiesel and diesel at various injection pressures. It was found that breakup time for biodiesel increases and breakup velocity decreases. Breakup velocity of biodiesel is less than diesel, this is due to higher sound velocity, density, viscosity and bulk modulus of biodiesel. High viscosity fuel suppresses the instabilities required for fuel jet to breakup and thus delays atomization and reduces fuel losses during injection. With the increase in fuel injection pressure, the breakup time for biodiesel is more than diesel, this is due its larger surface area of the spray and larger mixing time of biodiesel than diesel.
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38

Xi, Mingze. "Rational Design of Future Potential Electric Aircraft." Journal of Physics: Conference Series 2434, no. 1 (January 1, 2023): 012006. http://dx.doi.org/10.1088/1742-6596/2434/1/012006.

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Анотація:
Abstract With the development of science and technology, the shortage of fossil energy has become a problem that cannot be ignored. The main significance of studying electric aircraft is to reduce energy consumption and achieve green travel. The electric airplane project is very unusual. It can change the energy use of the world. If the electric airplane can be designed, it will be used in other fields, such as aviation. The advantages of electric aircraft, such as low cost, high efficiency, and sustainability, can reduce the world’s oil energy consumption. In addition, it is believed that many people have built electric vehicles. The noise of electric vehicles will be quieter than that of fossil fuel aircraft. This green energy can make the world develop and progress faster. Furthermore, the low price, energy conservation, environmental protection, and low cost have huge commercial potential. The paper organization mainly consists of the new battery, electric motor vs. jet, thermal energy, and required energy.
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39

Tasneem Abdalla, Tasneem Abdalla, Tasneem Abdalla Tasneem Abdalla, Qian Wang, Qian Wang, Tan Xiaoqiang, and Tan Xiaoqiang. "The Study on Dual Fuel Spray and Characteristics of Combustion of Diesel, Natural Gas and Dual Fuel." Journal of Energy Conservation 1, no. 1 (June 11, 2018): 14–30. http://dx.doi.org/10.14302/issn.2642-3146.jec-18-2135.

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Анотація:
Combustion of fossil fuels provides around 88% of total energy supply for modern society, and meanwhile causes many environ mental problems and social problems such as air pollution and energy crisis. Therefore,both at home and abroad are focusing on the research and development of natural gas engine recently. However, the mass production and application of this kind of engine are restricted by some unsolved technical difficulties. This paper explored the injection, combustion and emission processes of diesel/ natural gas and dual fuel engine based on Chemkin II, Fire software and Schlieren method. The experimental study on the mixing process of dual fuel jet was carried out by using high-speed Schlieren method in a constant volume bomb. Based on the Fire software, and then applied to Chemkin II software to analyze the effect of the initial temperature and pressure on the net heat production and combustion emissions. The results show that Dual fuel mechanism is capable of producing different heat production behaviors when varying the initial pressure and temperature CO2 emissions are minimized by changing the initial pressure above or below the atmospheric value. However, CO emissions are peaked when diesel fuel is used. The dual fuel engine minimizes the CO emissions amount caused by diesel fuel. Increasing the initial pressure eliminates dual fuel CO2 combustion emissions. The research of this paper is important to optimize the in cylinder combustion processes of natural gas engine, and have a certain important meaning to guide the development of diesel ignition dual fuel engine.
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40

Silva, Carla, Patricia Moniz, Ana Cristina Oliveira, Samuela Vercelli, Alberto Reis, and Teresa Lopes da Silva. "Cascading Crypthecodinium cohnii Biorefinery: Global Warming Potential and Techno-Economic Assessment." Energies 15, no. 10 (May 20, 2022): 3784. http://dx.doi.org/10.3390/en15103784.

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Анотація:
Prior to the commissioning of a new industrial biorefinery it is deemed necessary to evaluate if the new project will be beneficial or detrimental to climate change, one of the main drivers for the sustainable development goals (SDG) of the United Nations. In particular, how SDG 7, Clean and Efficient Energy, SDG 3, Good Health and Well Being, SDG 9, Industry Innovation and Infrastructure, and SDG 12, Responsible Production and Consumption, would engage in a new biorefinery design, beneficial to climate change, i.e., fostering SDG 13, Climate Action. This study uses life cycle assessment methodology (LCA) to delve in detail into the Global Warming Impact category, project scenario GHG savings, using a conventional and a dynamic emission flux approach until 2060 (30-year lifetime). Water, heat and electricity circularity are in place by using a water recirculation process and a combined heat and power unit (CHP). A new historical approach to derive low and higher-end commodity prices (chemicals, electricity, heat, jet/maritime fuel, DHA, N-fertilizer) is used for the calculation of the economic indicators: Return of investment (ROI) and inflation-adjusted return (IAR), based upon the consumer price index (CPI). Main conclusions are: supercritical fluid extraction is the hotspot of energy consumption; C. cohnii bio-oil without DHA has higher sulfur concentration than crude oil based jet fuel requiring desulfurization, however the sulfur levels are compatible with maritime fuels; starting its operation in 2030, by 2100 an overall GHG savings of 73% (conventional LCA approach) or 85% (dynamic LCA approach) is projected; economic feasibility for oil productivity and content of 0.14 g/L/h and 27% (w/w) oil content, respectively (of which 31% is DHA), occurs for DHA-cost 100 times higher than reference fish oil based DHA; however future genetic engineering achieving 0.4 g/L/h and 70% (w/w) oil content (of which 31% is DHA), reduces the threshold to 20 times higher cost than reference fish oil based DHA; N-fertilizer, district heating and jet fuel may have similar values then their fossil counterparts.
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41

Abhishek J., Parekh. "Research on Aerofoil Shape to Increase the Effectiveness of Aeroplanes." International Journal for Research in Applied Science and Engineering Technology 9, no. 9 (September 30, 2021): 2165–69. http://dx.doi.org/10.22214/ijraset.2021.38267.

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Анотація:
Abstract: In the modern era where emphasis on air travels is increasing day by day. There is no near alternative of jet fuel. In such situation where fossil fuel use becomes bounded than, we should try to increase efficiency from available resources so as to push world towards sustainable development. Efficiency of aeroplanes greatly depends on couple of major factors like load carried, type of fuel used, power of engine installed, etc. But if we take similar aircrafts with similar loads than one criterion plays pivotal role in efficiency of aircrafts and that is shape of aerofoil wings. Angle of attack also depends on this. Optimum shape of aerofoil has always been topic of research for engineers. In present paper, an aerofoil shape with bottom surface backlash is analysed in ABAQUS software. Different modes of failure help in better designing as well as maximum bearable load by aerofoil shape. Keyword: 1. Aeronautical engineering, 2. Fluid Mechanics, 3. Analysis on ABAQUS, 4. Computational fluid dynamics.
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42

Sabarman, J. S., E. H. Legowo, D. I. Widiputri, and A. R. Siregar. "Bioavtur Synthesis from Palm Fatty Acid Distillate through Hydrotreating and Hydrocracking Processes." Indonesian Journal of Energy 2, no. 2 (August 30, 2019): 99–110. http://dx.doi.org/10.33116/ije.v2i2.40.

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Анотація:
Increasing concern in fossil fuel depletion and CO2 emissions create an urgent need for biofuel substitution. Bio-jet fuel is a possible alternative for conventional jet fuels which currently accounts for 2% of the world’s CO2 emission. Palm Fatty Acid Distillate (PFAD) is the byproduct of palm oil refinery process, which has a potential to become a promising raw material for the synthesis of bioavtur due to its high free fatty acid content. The oil-to-jet pathway is a possible route to produce bioavtur from PFAD, which includes hydrotreating, hydrocracking, and hydroisomerization processes. This research aims to investigate the hydrotreating and hydrocracking processes. The parameters that were investigated are temperature, solvent to PFAD ratio, catalyst loading, and pressure. The parameters variations were as follows: the temperature at 350oC and 400oC, the pressure at 40 bar and 32.5 bar, the solvent to PFAD ratio at 2:1 and 1:1, and the catalyst loading (%wt) at 1%, 2%, and 3%. Presulfided NiMo/γ-Al2O3 PIDO 120 1.3 was used for one-step hydrotreating and hydrocracking processes. Results indicated that the 400oC provided better free fatty acid (FFA) conversion. FFA is also almost completely removed when the catalyst used is 3% weight. Solvent to PFAD ratio affected the FFA conversion marginally, while higher catalyst loading (3%) improved the FFA conversion. Gas chromatography results show that the hydrocarbon chains are successfully hydrocracked into C9-C17. The best selectivity of the product to bioavtur range was calculated at 68.99%. Solvent ratio affects the hydrocracking more significantly than the catalyst loading. One sample with temperature operation 400oC and solvent to PFAD ratio 1:1 was in the range of conventional avtur density. With the method used in this study, it can be concluded that PFAD is a promising raw material for bioavtur. Keywords: Palm Fatty Acid Distillate (PFAD), hydrotreating, hydrocracking, bioavtur
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43

Fagerström, Anton, Omar Abdelaziz, Sofia Poulikidou, Adam Lewrén, Christian Hulteberg, Ola Wallberg, and Tomas Rydberg. "Economic and Environmental Potential of Large-Scale Renewable Synthetic Jet Fuel Production through Integration into a Biomass CHP Plant in Sweden." Energies 15, no. 3 (February 2, 2022): 1114. http://dx.doi.org/10.3390/en15031114.

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Анотація:
The potential of bio-electro-jet fuel (BEJF) production with integration into an existing biomass-based combined heat and power (CHP) facility was investigated. The BEJF is produced via Fischer–Tropsch (F–T) synthesis from biogenic CO2 and H2 obtained by water electrolysis. Techno-economic (TEA)- and life. cycle (LCA)- assessments were performed to evaluate the production cost and environmental impact of the BEJF production route. The BEJF mass fraction reached 40% of the total F–T crude produced. A reduction of 78% in heating demands was achieved through energy integration, leading to an increase in the thermal efficiency by up to 39%, based on the F–T crude. The total production cost of BEJF was in the range of EUR 1.6–2.5/liter (EUR 169–250/MWh). The GWP of the BEJF was estimated to be 19 g CO2-eq per MJ BEJF. The reduction potential in GWP in contrast to the fossil jet baseline fuel varied from 44% to more than 86%. The findings of this study underline the potential of BEJF as a resource-efficient, cost-effective, and environmentally benign alternative for the aviation sector. The outcome is expected to be applicable to different geographical locations or industrial networks when the identified influencing factors are met.
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44

Azami, Muhammad Hanafi, and Mark Savill. "Comparative study of alternative biofuels on aircraft engine performance." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 8 (June 22, 2016): 1509–21. http://dx.doi.org/10.1177/0954410016654506.

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Анотація:
Aviation industries are vulnerable to the energy crisis and simultaneously posed environmental concerns. Proposed engine technology advancements could reduce the environmental impact and energy consumption. Substituting the source of jet fuel from fossil-based fuel to biomass-based fuel will help reduce emissions and minimize the energy crisis. The present paper addresses the analysis of aircraft engine performance in terms of thrust, fuel flow and specific fuel consumption at different mixing ratio percentages (20%, 40%, 50%, 60% and 80%) of alternative biofuel blends already used in flight test (Algae biofuel, Camelina biofuel and Jatropha biofuel) at different flight conditions. In-house computer software codes, PYTHIA and TURBOMATCH, were used for the analysis and modeling of a three-shaft high-bypass-ratio engine which is similar to RB211-524. The engine model was verified and validated with open literature found in the test program of bio-synthetic paraffinic kerosene in commercial aircraft. The results indicated that lower heating value had a significant influence on thrust, fuel flow and specific fuel consumption at every flight condition and at all mixing ratio percentages. Wide lower heating value differences between two fuels give a large variation on the engine performances. Blended Kerosene–Jatropha biofuel and Kerosene–Camelina biofuel showed an improvement on gross thrust, net thrust, reduction of fuel flow and specific fuel consumption at every mixing ratio percentage and at different flight conditions. Moreover, the pure alternative of Jatropha biofuel and Camelina biofuel gave much better engine performances. This was not the case for the Kerosene–Algae blended biofuel. This study is a crucial step in understanding the influence of different blended alternative biofuels on the performance of aircraft engines.
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45

Minakov, Andrey V., Viktor A. Kuznetsov, Artem A. Dekterev, Igor S. Anufriev, Evgeny P. Kopyev, and Sergey V. Alekseenko. "Comparative Analysis of Numerical Methods for Simulating N-Heptane Combustion with Steam Additive." Energies 16, no. 1 (December 20, 2022): 25. http://dx.doi.org/10.3390/en16010025.

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Анотація:
Currently, thermal power plants operating on hydrocarbon fuels (gas, fuel oil, peat, shale, etc.) are one of the main sources of electricity. An effective and promising method for suppressing harmful emissions (NOx, carbon oxides, soot) from the combustion of fossil fuels is the injection of steam into the combustion chamber. The influence of various mathematical submodels was studied on the accuracy of the numerical simulation of the process of n-heptane combustion in a laboratory burner with steam additive to the reaction zone as a promising chemical engineering method for the disposal of substandard liquid fuels and combustible waste with the production of thermal energy. The problem was solved in a three-dimensional stationary formulation. Systematic verification of these submodels, and a comparison of the results of the calculation with the experimental data obtained were carried out. The comparison with the experimental data was carried out for gas components and temperature distribution at the burner outlet; high agreement of the results was achieved. Optimal submodels of the methodology for calculating the process of fuel combustion in a jet of steam were determined. The best agreement with the experiment data was obtained using the EDC model in combination with a mechanism consisting of 60 components and 305 elementary reactions. More correct simulation results were obtained using the RSM turbulence model and the DO radiation model.
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46

Li, Tianyi. "The performances and applications of gas turbines in the aviation industry." Applied and Computational Engineering 11, no. 1 (September 25, 2023): 104–10. http://dx.doi.org/10.54254/2755-2721/11/20230217.

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Анотація:
This paper focuses on using gas turbines in various industries, particularly aviation, due to their unique power-to-weight ratio. It provides a detailed description of how gas turbines operate based on the thermodynamic Brayton cycle, which includes compressors, combustors, and power turbines. Additionally, the paper analyses both ideal and realistic cycles of gas turbines. Despite numerous advantages, gas turbines have limitations, such as high fuel consumption. However, technological advancements have led to the development of more efficient and quieter gas turbines. The paper explains the classification of jet engines, including turbojets, turboprops, and turbofans, each with specific applications. Moreover, the paper discusses the efforts to reduce the use of fossil fuels in aviation due to the increasing awareness of the impact of climate change. Scientists and engineers are exploring substitute fuels and materials and developing gas turbine systems that maximize work generated with minimal combustion; thus, this paper also highlights the importance of developing more efficient and environmentally friendly gas turbines to reduce the industry's carbon footprint while maintaining their productivity.
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47

Petro, Lucia M., Revocatus Machunda, Siza Tumbo, and Thomas Kivevele. "Theoretical and Experimental Performance Analysis of a Novel Domestic Biogas Burner." Journal of Energy 2020 (September 16, 2020): 1–9. http://dx.doi.org/10.1155/2020/8813254.

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Анотація:
The inefficient indoor burning of fuelwood on traditional cookstoves generates pollutants, primarily carbon monoxide and many other human health-damaging emissions. It is from this risk that it is necessary to have an immediate shift to alternative cleaner fuel sources. Biogas, which is among the biofuels from biomass, is one of the resources that play a considerable part in a more diverse and sustainable global energy mix. For domestic purposes in rural areas of Tanzania, biogas provides a better option that can supplement the use of fossil fuels such as wood, charcoal, and kerosene, which is nonrenewable. However, the low efficiency experienced in the locally made biogas burners hinders the large-scale use of biogas among the population in the country. With the locally made burners, the users of biogas for the domestic application face problems including heat loss and high gas consumption which affects the whole cooking process. It is against this backdrop that the current study objectives incline on designing and improving the efficiency of the locally manufactured burners to achieve the uniform flow of fuel in the mixing chamber, which will result to the consistent heat distribution around the cooking pot. The optimization of the burner was done by using computational fluid dynamics (CFD) through varying the number of flame portholes and air holes as well as the size of the jet before fabrication. The increased efficiency of the burner has also contributed by the addition of the fuel distributor. The results showed that the optimum hole diameter of the jet was 2.5 mm and that of the manifold was 100 mm. The currently developed biogas burner was tested and compared with the other two locally made burners. The water boiling test (WBT) on these three burners showed that the developed burner has a thermal efficiency of 67.01% against 54.61% and 58.82% of the Centre for Agricultural Mechanization and Rural Technology (CARMATEC) and Simgas, respectively. Additionally, the fuel consumption of the developed burner was 736 g/L as compared to 920 g/L for CARMARTEC and 833 g/L for that of Simgas. The developed burner and its corresponding cookstove are both environmentally friendly and economical for household utilization in Tanzania and other developing countries.
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48

López-Rosales, Alan, Katia Ancona-Canché, Juan Chavarria-Hernandez, Felipe Barahona-Pérez, Tanit Toledano-Thompson, Gloria Garduño-Solórzano, Silvia López-Adrian, Blondy Canto-Canché, Erik Polanco-Lugo, and Ruby Valdez-Ojeda. "Fatty Acids, Hydrocarbons and Terpenes of Nannochloropsis and Nannochloris Isolates with Potential for Biofuel Production." Energies 12, no. 1 (December 31, 2018): 130. http://dx.doi.org/10.3390/en12010130.

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Анотація:
Marine microalgae are a promising feedstock for biofuel production given their high growth rates and biomass production together with cost reductions due to the use of seawater for culture preparation. However, different microalgae species produce different families of compounds. Some compounds could be used directly as fuels, while others require thermochemical processing to obtain quality biofuels. This work focuses on the characterization of three marine microalgae strains native in Mexico and reported for the first time. Ultrastructure and phylogenetic analysis, suggested that they belong to Nannochloropsis sp. (NSRE-1 and NSRE-2) and Nannochloris sp. (NRRE-1). The composition of their lipid fractions included hydrocarbons, triacylglycerides (TAGs), free fatty acids (FFAs) and terpenes. Based on theoretical estimations from TAG and FFA composition, the potential biodiesels were found to comply with six of the seven estimated properties (ASTM D6751 and EN 14214). On the other hand, hydrocarbons and terpenes synthesized by the strains have outstanding potential as precursors for the production of other renewable fuels, mainly green diesel and bio-jet fuel, which are “drop-in” fuels with quality properties similar to fossil fuels. The validity of this theoretical analysis was demonstrated for the oxygenates of strain NSRE-2, which were experimentally hydrodeoxygenated, obtaining a high-quality renewable diesel as the reaction product.
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49

Mustafa, Kamarul ‘Asyikin, Murniati Syaripuddin, Norlaili Ismail, Nazrul Fariq Makmor, and Mohamad Fakri Ishak. "Pico Hydro Generation System for Building’s Supplementary Energy." Jurnal Kejuruteraan si4, no. 1 (September 30, 2021): 137–43. http://dx.doi.org/10.17576/jkukm-2021-si4(1)-17.

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Анотація:
Renewable energy is an important source in supplying energy to the masses as it is sustainable, environmentally friendly, and require less maintenance cost compared to the conventional fossil fuel resources. This paper describes the study of a pico hydro generation system. The power generation system uses water utilized by a building as the source to generate energy. In the study, the system prototype is designed using several combinations of piping system where different sizes, shapes, and turbine positions are used. The energy from the water flowing through the piping system will be converted into electrical energy through the turbine system that is placed in the main water tank. The best combination of pipeline system for the prototype is by using two different positions of water jet. This combination requires lower water pressure and is able to generate 198 W of energy.
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50

Siddanathi, S. L., L. G. Westerberg, H. O. Åkerstedt, H. Wiinikka, and A. Sepman. "Computational modeling and temperature measurements using emission spectroscopy on a non-transferred plasma torch." AIP Advances 13, no. 2 (February 1, 2023): 025019. http://dx.doi.org/10.1063/5.0129653.

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Анотація:
A non-transferred plasma torch is a device used to generate a steady thermal plasma jet. Plasma torches have the potential to replace fossil fuel burners used as heat sources in the process industry. Today, however, the available plasma torches are of small scale compared to the power used in the burners in the process industry. In order to understand the effects of large scales on the plasma flow dynamics, it is essential to understand the operation of the plasma torch under different operating conditions and for different geometries. In this study, the analysis of a non-transferred plasma torch has been carried out using both computational and experimental methods. Computationally, the magnetohydrodynamic (MHD) equations are solved using a single-fluid model on a 2D axisymmetric torch geometry. The experiments are performed using emission spectroscopy to measure the plasma jet temperature at the outlet. This paper explains the changes in the arc formation, temperature, and velocity for different working gases and power inputs. Furthermore, the possibilities and disadvantages of the MHD approach, considering a local thermal equilibrium, are discussed. It was found that in general, the computational temperature obtained is supported by the experimental and equilibrium data. The computational temperatures agree by within 10% with the experimental ones at the center of the plasma torch. The paper concludes by explaining the significant impact of input properties like working gas and power input on the output properties like velocity and temperature of plasma jet.
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