scholarly journals Tribological Performance of Biomass-Derived Bio-Alcohol and Bio-Ketone Fuels

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5331
Author(s):  
Omid Doustdar ◽  
Soheil Zeraati-Rezaei ◽  
Jose Martin Herreros ◽  
Athanasios Tsolakis ◽  
Karl D. Dearn ◽  
...  
Keyword(s):  
Molecular Structure ◽  
High Frequency ◽  
Alternative Fuels ◽  
Tribological Performance ◽  
Hydroxyl Group ◽  
Propulsion Systems ◽  
Lubrication Film ◽  
Steel Disc ◽  
And Performance ◽  
Worn Surface

This study relates to developing future alternative fuels and focuses on the effects of a fuel’s molecular structure on its properties and performance in advanced propulsion systems. The tribological performance of various biomass-derived oxygenated alternative fuels, including butanol, pentanol, cyclopentanol, cyclopentanone, and gasoline and their blends with diesel, was investigated. Lubricity tests were conducted using a high-frequency reciprocating rig (HFRR). Cyclopentanone-diesel and cyclopentanol-diesel blends result in smaller wear scar sizes compared to using their neat forms. A lower steel disc contaminated with the alternative fuels during the HFRR tests resulted in worn surface roughness values lower than those of the neat diesel by up to 20%. It is believed that these reductions are mainly due to the presence of the hydroxyl group and the carbonyl group in alcohols and ketones, respectively, which make them more polar and consequently helps the formation of the protective lubrication film on the worn moving surfaces during the sliding process. Overall, the results from this study indicate that environmentally friendly cyclopentanol and cyclopentanone are practical and efficient fuel candidates for future advanced propulsion systems.

Size and Performance Tradeoffs in Micro-Inductors for High Frequency DC-DC Conversion

2009 ◽  
Vol 45 (10) ◽  
pp. 4234-4237 ◽  
Author(s):  
R. Meere ◽  
T. O'Donnell ◽  
N. Wang ◽  
N. Achotte ◽  
S. Kulkarni ◽  
...  
Keyword(s):  
High Frequency ◽  
And Performance

A One Dimensional, Time Dependent Inlet / Engine Numerical Simulation for Aircraft Propulsion Systems

1997 ◽  
Author(s):  
Doug Garrard ◽  
Milt Davis ◽  
Steve Wehofer ◽  
Gary Cole
Keyword(s):  
Numerical Simulation ◽  
Gas Turbine ◽  
High Frequency ◽  
Gas Turbine Engine ◽  
Simulation System ◽  
Time Dependent ◽  
Propulsion Systems ◽  
Turbine Engine ◽  
One Dimensional ◽  
Supersonic Inlet

The NASA Lewis Research Center (LeRC) and the Arnold Engineering Development Center (AEDC) have developed a closely coupled computer simulation system that provides a one dimensional, high frequency inlet / engine numerical simulation for aircraft propulsion systems. The simulation system, operating under the LeRC-developed Application Portable Parallel Library (APPL), closely coupled a supersonic inlet with a gas turbine engine. The supersonic inlet was modeled using the Large Perturbation Inlet (LAPIN) computer code, and the gas turbine engine was modeled using the Aerodynamic Turbine Engine Code (ATEC). Both LAPIN and ATEC provide a one dimensional, compressible, time dependent flow solution by solving the one dimensional Euler equations for the conservation of mass, momentum, and energy. Source terms are used to model features such as bleed flows, turbomachinery component characteristics, and inlet subsonic spillage while unstarted. High frequency events, such as compressor surge and inlet unstart, can be simulated with a high degree of fidelity. The simulation system was exercised using a supersonic inlet with sixty percent of the supersonic area contraction occurring internally, and a GE J85-13 turbojet engine.

Fabrication and performance of Fe-based magnetic thin film inductor for high-frequency application

2008 ◽  
Vol 320 (20) ◽  
pp. e963-e966 ◽  
Author(s):  
Yong Zhou ◽  
Zhi-Min Zhou ◽  
Ying Cao ◽  
Xiao-Yu Gao ◽  
Wen Ding
Keyword(s):  
Thin Film ◽  
High Frequency ◽  
Magnetic Thin Film ◽  
High Frequency Application ◽  
And Performance

scholarly journals Ecological Aspects of Implementing Prospective Propulsion Schemes of Short and Medium Haul Aircrafts

2015 ◽  
Vol 4 (2) ◽  
pp. 67-72 ◽  
Author(s):  
Самойлов ◽  
M. Samoylov ◽  
Бурцев ◽  
S. Burtsev ◽  
Симаков ◽  
...  
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Alternative Fuels ◽  
Fuel Efficiency ◽  
Civil Aviation ◽  
Propulsion Systems ◽  
Hybrid Propulsion ◽  
Ecological Aspects ◽  
Hybrid Power Plant ◽  
Traditional Patterns

The influence of the circuitry of the hybrid power plant short and medium haul aircraft on their fuel efficiency and environmental characteristics have been investigated. Directions of improvement of traditional patterns of power plants of aircraft on the example of PD-14 engine were analyzed. It has been shown that the use of turbojet engines and traditional schemes operating on aviation kerosene, will not allow to fulfill the demands made by the International Civil Aviation Organization (ICAO) to perspective plane 2025–2035. The analysis of the three schemes hybrid propulsion systems has been performed. It has been shown that using the presented hybrid propulsion systems of alternative fuels can reduce CO2 emissions by 19% to 20% compared with conventional turbojet engines, which run on kerosene TS-1. It has been shown that this fuel efficiency is increased by 2–3%, and the total mass of the power plant increases of 6 to 16%.

On the Corrosion Behavior of Refined Bio-Oil during Rubbing Process

2011 ◽  
Vol 130-134 ◽  
pp. 1310-1313
Author(s):  
Yu Fu Xu ◽  
Wen Dong Li ◽  
Xian Guo Hu ◽  
Qiong Jie Wang
Keyword(s):  
Surface Roughness ◽  
Corrosion Behavior ◽  
High Frequency ◽  
Energy Dispersive Spectrometer ◽  
Wear Depth ◽  
Chemical Structures ◽  
Bio Oil ◽  
Component Content ◽  
Acidic Component ◽  
Worn Surface

The corrosion behavior during friction of refined bio-oil by distillation process was evaluated by high frequency reciprocating test rig. Both scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) were used to investigate the morphology and active elements contents on the rubbed surface on steel disk. The chemical structures of the oils and the topography and surface roughness of the wear scar were also studied by FTIR and surface roughness tester as well, respectively. The experimental results showed that corrosion behavior of bio-oil was improved after refining since the wear depth was 3.75µm and the worn surface roughness was 0.172µm, while they were 12.5µm and 0.217µm before refining. It was concluded that corrosion degree of worn surface was decreased after the bio-oil was refined, which was ascribed to the decrease of the acidic component content after the refining process.

Photosensitive Polyimide having low loss tangent for RF application

2018 ◽  
Vol 2018 (1) ◽  
pp. 000476-000482 ◽  
Author(s):  
Masao Tomikawa ◽  
Hitoshi Araki ◽  
Yohei Kiuchi ◽  
Akira Shimada
Keyword(s):  
Molecular Structure ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
High Frequency ◽  
Low Dielectric Constant ◽  
Low Loss ◽  
Elongation At Break ◽  
Low Dielectric ◽  
The Poor

Abstract Progress of 5G telecommunication and mm radar for autopilot, high frequency operation is required. Insulator materials having low loss at high frequency is desired for the applications. We designed the low dielectric constant, and low dielectric loss materials examined molecular structure of the polyimide and found that permittivity 2.6 at 20GHz, dielectric loss 0.002. Furthermore, in consideration of mechanical properties such as the toughness and adhesion to copper from a point of practical use. Dielectric properties largely turned worse when giving photosensitivity. To overcome the poor dielectric properties, we designed the photosensitive system. After all, we successfully obtained 3.5 of dielectric constant and 0.004 of dielectric loss, and 100% of elongation at break. In addition, we offered a B stage sheet as well as varnish. These materials are applicable to re-distribution layer of FO-WLP, Interposer and other RF applications for microelectronics.

scholarly journals Criteria and Decision Support for A Sustainable Choice of Alternative Marine Fuels

2020 ◽  
Vol 12 (9) ◽  
pp. 3623
Author(s):  
Karin Andersson ◽  
Selma Brynolf ◽  
Julia Hansson ◽  
Maria Grahn
Keyword(s):  
Decision Support ◽  
Emission Reduction ◽  
Alternative Fuels ◽  
Reduction Potential ◽  
Ghg Emission ◽  
Propulsion Systems ◽  
Good Decision ◽  
Life Cycle Perspective ◽  
Ghg Reduction ◽  
Energy Conversion Systems

To reach the International Maritime Organization, IMO, vision of a 50% greenhouse gas (GHG) emission reduction by 2050, there is a need for action. Good decision support is needed for decisions on fuel and energy conversion systems due to the complexity. This paper aims to get an overview of the criteria types included in present assessments of future marine fuels, to evaluate these and to highlight the most important criteria. This is done using a literature review of selected scientific articles and reports and the authors’ own insights from assessing marine fuels. There are different views regarding the goal of fuel change, what fuel names to use as well as regarding the criteria to assess, which therefore vary in the literature. Quite a few articles and reports include a comparison of several alternative fuels. To promote a transition to fuels with significant GHG reduction potential, it is crucial to apply a life cycle perspective and to assess fuel options in a multicriteria perspective. The recommended minimum set of criteria to consider when evaluating future marine fuels differ somewhat between fuels that can be used in existing ships and fuels that can be used in new types of propulsion systems.

scholarly journals The Effect of Surface Texturing on Dry Gross Fretting

Lubricants ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 92 ◽  
Author(s):  
Agnieszka Lenart ◽  
Pawel Pawlus ◽  
Slawomir Wos ◽  
Andrzej Dzierwa
Keyword(s):  
Friction And Wear ◽  
Surface Texturing ◽  
Tribological Performance ◽  
Disc Surface ◽  
Abrasive Jet Machining ◽  
Wear And Friction ◽  
Steel Disc ◽  
Disc Configuration ◽  
Effect Of Surface ◽  
Ball On Disc

The effect of steel disc surface texturing on dry gross fretting in a ball-on-disc configuration was studied. Dimples were created with abrasive jet machining. The tribological performance of sliding pairs, steel–steel and steel–ceramics, was experimentally studied. The character of surface texturing effect was related to the dominant wear type. During steel–steel contact, the presence of dimples on disc surfaces could lead to increases in wear and friction. However, the escape of wear debris into dimples could result in reductions of friction and wear in the steel–ceramics configuration.

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