Effect of fuel injection timing and pressure on combustion, emissions and performance characteristics of a single cylinder diesel engine

Biomass-derived jet (bio-jet) fuel has become a key element in the aviation industry׳s strategy to reduce operating costs and environmental impacts. Researchers from the oil-refining industry, the aviation industry, government, biofuel companies, agricultural organizations, and academia are working toward developing a commercially viable and sustainable process that produces a long-lasting renewable jet fuel with low production costs and low greenhouse emissions. This jet fuel, additionally, must meet ASTM International specifications and potentially be a 100% drop-in replacement for current petroleum jet fuel. In this study, the current technologies for producing renewable jet fuels, categorized by alcohols-to-jet, oil-to-jet, syngas-to-jet, and sugar-to-jet pathways are reviewed. The main challenges for each technology pathway, including conceptual process design, process economics and life-cycle assessment of greenhouse gas emissions are discussed. Although the feedstock price and availability and energy intensity of the process are significant barriers, biomass-derived jet fuel has the potential to replace a significant portion of conventional jet fuel required to meet commercial and military demand.

/pdf/bio-jet-fuel-conversion-technologies-gxujxssbxg.pdf

Bio-Jet Fuel Conversion Technologies

https://pure.tue.nl/ws/files/67843762/1_s2.0_S0306261917303744_main.pdf

Effect of pitch angle on power performance and aerodynamics of a vertical axis wind turbine

Lignocellulosic biomass is the most abundant organic carbon source and has received a great deal of interest as renewable and sustainable feedstock for the production of potential biofuels and value-added chemicals with a wide range of designed catalytic systems. However, those natural polymeric materials are composed of short-chain monomers (typically C6 and C5 sugars) and complex lignin molecules containing plenty of oxygen, resulting in products during the downstream processing having low-grade fuel properties or limited applications in organic syntheses. Accordingly, approaches to increase the carbon-chain length or carbon atom number have been developed as crucial catalytic routes for upgrading biomass into energy-intensive fuels and chemicals. The primary focus of this review is to systematically describe the recent examples on the selective synthesis of long-chain oxygenates via different C-C coupling catalytic processes, such as Aldol condensation, hydroalkylation/alkylation, oligomerization, keto...

Carbon-Increasing Catalytic Strategies for Upgrading Biomass into Energy-Intensive Fuels and Chemicals

Scientific studies have demonstrated that it is possible to generate a wide variety of bioenergy from biomass residues and waste, and however its cost is not competitive with petro-fuels and other renewable energy. On-going efforts are continued extensively to improve conversion technologies in order to reduce production costs. The present review focuses on the conversion technologies for transforming biomass residues and waste to biofuels, specifically their technological concepts, options and prospects for implementation are addressed. The emerging developments in the two primary conversion pathways, namely the thermochemical (i.e. gasification, liquefaction, and pyrolysis) and biochemical (i.e. anaerobic digestion, alcoholic fermentation and photobiological hydrogen production) conversion techniques, are evaluated. Additionally, transesterification, which appears to be the simplest and most economical route to produce biodiesel in large quantity, is discussed. Lastly, the strategies for direct conversion of biomass residues and waste to bioelectricity including the use of combustion and microbial fuel cells are reviewed.

/pdf/waste-to-bioenergy-a-review-on-the-recent-conversion-2n111rm8z0.pdf

Waste to bioenergy: a review on the recent conversion technologies

Spray and atomization of diesel fuel and its alternatives from a single-hole injector using a common rail fuel injection system

Hydrocarbon fuels from vegetable oils via hydrolysis and thermo-catalytic decarboxylation

Alternative fuel produced from thermal pyrolysis of waste tires and its use in a di diesel engine

Horizontal-axis wind turbines (HAWTs) are the primary devices used in the wind energy sector. Systems used to evaluate the design of turbine blades and generators are key to improve the performance of HAWTs. Analysis of aerodynamic performance in turbine blades focuses on wind speed, rotational speed, and tip speed ratios (TSRs). This paper reviews computational as well as experimental methods used to measure the aerodynamic performance of HAWT blades. Among the numerical methods, we examine classical blade element momentum (BEM) theory and the modified BEM as well as computational fluid dynamics (CFD) and the BEM-CFD mixed approach. We also discuss the current computational methods for investigating turbine wake flows. Among the experimental methods, we examine field testing and wind tunnel experiment including aerodynamic torque measurement and blockage effects. A comparison of numerical and experimental approaches can help to improve accuracy in the prediction of wind turbine performance and facilitate the design of HAWT blades.

Wei Cheng Wang

Papers

Bio-Jet Fuel Conversion Technologies

Spray and atomization of diesel fuel and its alternatives from a single-hole injector using a common rail fuel injection system

Hydrocarbon fuels from vegetable oils via hydrolysis and thermo-catalytic decarboxylation

Alternative fuel produced from thermal pyrolysis of waste tires and its use in a di diesel engine

Review of computational and experimental approaches to analysis of aerodynamic performance in horizontal-axis wind turbines (HAWTs)