scholarly journals Spray Combustion Chamber: History and Future of a Unique Test Facility

2017 ◽  
Author(s):  
Andreas Schmid ◽  
Naoki Yamada
Keyword(s):  
Combustion Chamber ◽  
High Speed ◽  
High Energy ◽  
Injection System ◽  
Test Facility ◽  
Spray Combustion ◽  
Future Research ◽  
Nozzle Flow ◽  
Shipping Industry ◽  
Optical Access

Large marine two-stroke diesel engines still represent the major propulsion system for merchant shipping. Withsteadily increasing transport demands, rising operational costs and stricter environmental legislations, the global marine shipping industry finds itself facing the challenge to future-proof its fleet. In order to comply with international maritime organizations emission standards (TIER II and TIER III), highly sophisticated and flexible combustion systems are demanded. With the help of spray and combustion research such systems can be developed and continuously improved. A highly valuable tool to investigate sprays of large marine diesel injectors under engine relevant conditions is the Spray Combustion Chamber (SCC). This paper reviews the history of the SCC, shows todays possibilities and looks into the near future of research involving large marine two-stroke engines. The SCC was built during the first Hercules project (I.P.-HERCULES, WP5, [1]). The initial setup focused on fundamental investigations comprising the application of highly flexible thermodynamic conditions. During follow-up projects (Hercules beta [2] and Hercules C [3]) the SCC was continuously developed, and a variety of influences on spray and combustion were experimentally assessed. The initial SCC design focused on maximum optical access as well as the applicability of a wide span of optical techniques. Single-hole nozzles were utilized to generate reference data to optimize existing spray and combustion simulation models. Different fuel types and fuel qualities were investigated and effects of the in-nozzle flow on spray morphology was identified. A sound set of results was achieved and published in several (internal and public) reports. Over the years, spray research at Winterthur Gas& Diesel has turned its focus from basic spray investigations to more detailed cavitation and in-nozzle flow examinations [4], [5]. Future research on the SCC will focus on investigations of more engine related topics, as, for example, the application of a fuel flexible injection system as is currently developed in the HERCULES-2 project [6]. Significant design modifications of the initial setup were necessary, as the injector positions and therefore exposure of the spray relative to the swirl were not fully congruent with real engine conditions. As a consequence, the new setup includes some minor drawbacks, e.g. the optical access of the nozzle tip is only visible from one side of the chamber. This means that line-of-sight methods are currently only possible at selected positions in the centre of the chamber. Therefore, a new setup was installed to illuminate the spray, consisting of a high speed, high energy laser (100 kHz, 100 W) and special optics. In order to obtain enhanced optical access, tangential windows were re- arranged, now pointing directly at the nozzle. With this setup, a first set of images was realized, showing a realspray as it occurs in large marine two-stroke diesel engines.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4734

scholarly journals Systems Design and Experimental Evaluation of a High-Altitude Relight Test Facility

2016 ◽  
Author(s):  
Brendan Paxton ◽  
Samir B. Tambe ◽  
San-Mou Jeng
Keyword(s):  
High Altitude ◽  
Gas Turbine ◽  
Experimental Evaluation ◽  
High Speed ◽  
Ambient Air ◽  
High Energy ◽  
Diagnostic Methods ◽  
Test Facility ◽  
Fuel Vapor ◽  
Gas Turbine Combustor

Novel advances in gas turbine combustor technology, led by endeavors into fuel efficiency and demanding environmental regulations, have been fraught with performance and safety concerns. While the majority of low emissions gas turbine engine combustor technology has been necessary for power-generation applications, the push for ultra-low NOx combustion in aircraft jet engines has been ever present. Recent state-of-the-art combustor designs notably tackle historic emissions challenges by operating at fuel-lean conditions, which are characterized by an increase in the amount of air flow sent to the primary combustion zone. While beneficial in reducing NOx emissions, the fuel-lean mechanisms that characterize these combustor designs rely heavily upon high-energy and high-velocity air flows to sufficiently mix and atomize fuel droplets, ultimately leading to flame stability concerns during low-power operation. When operating at high-altitude conditions, these issues are further exacerbated by the presence of low ambient air pressures and temperatures, which can lead to engine flame-out situations and hamper engine relight attempts. To aid academic and commercial research ventures into improving the high-altitude lean blow-out (LBO) and relight performance of modern aero turbine combustor technologies, the High-Altitude Relight Test Facility (HARTF) was designed and constructed at the University of Cincinnati Combustion & Fire Research Laboratory (CFRL). This paper presents an overview of its design and an experimental evaluation of its abilities to facilitate optically-accessible combustion and spray testing for aero engine combustor hardware at simulated high-altitude conditions. Extensive testing of its vacuum and cryogenic air-chilling capabilities was performed with regard to end-user control — the creation and the maintenance of a realistic high-altitude simulation — providing a performance limit reference when utilizing the modularity of the facility to implement different aero turbine combustor hardware. Ignition testing was conducted at challenging high-altitude windmilling conditions with a linearly-arranged five fuel-air swirler array to replicate the implementation of a multi-cup gas turbine combustor sector and to evaluate suitable diagnostic tools for the facility. High-speed imaging, for example, was executed during the ignition process to observe flame kernel generation and propagation throughout the primary, or near-field, combustion zones. In the evaluation performed, the HARTF was found to successfully simulate the atmospheric environments of altitudes ranging from sea level to beyond 10,700 m for the employed combustor sector. Diagnostic methods found compatible with the facility include high-speed flame imaging, combustion emission analysis, laser light sheet spray visualization, phase Doppler particle analysis (PDPA), and high-speed particle image velocimetry (HSPIV). Herein discussed are correlations drawn — linking altitude simulation capability to the size of the implemented combustor hardware — and challenges found — vacuum sealing, low pressure fuel injection, fuel vapor autoignition, and frost formation.

Spray Combustion Chamber with Optical Access, Ignition Zone Visualization and First Raman Measurements of Local Air-Fuel Ratio

1986 ◽  
Author(s):  
E. Scheid ◽  
F. Pischinger ◽  
K. F. Knoche ◽  
H.-J. Daams ◽  
E. P. Hassel ◽  
...  
Keyword(s):  
Combustion Chamber ◽  
Spray Combustion ◽  
Optical Access ◽  
Fuel Ratio ◽  
Ignition Zone

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Scalable Active Optical Access Network Using Variable High-Speed PLZT Optical Switch/Splitter

2012 ◽  
Vol E95-B (3) ◽  
pp. 730-739 ◽  
Author(s):  
Kunitaka ASHIZAWA ◽  
Takehiro SATO ◽  
Kazumasa TOKUHASHI ◽  
Daisuke ISHII ◽  
Satoru OKAMOTO ◽  
...  
Keyword(s):  
High Speed ◽  
Optical Switch ◽  
Access Network ◽  
Optical Access ◽  
Optical Access Network

Research on High-Speed Cutting of Cr12MoV Hardened Steel - A Review

2020 ◽  
Vol 15 ◽  
Author(s):  
Fei Sun ◽  
Guohe Li ◽  
Qi Zhang ◽  
Meng Liu
Keyword(s):  
High Speed ◽  
Cutting Temperature ◽  
High Hardness ◽  
High Strength ◽  
Hardened Steel ◽  
Parameters Optimization ◽  
Future Research ◽  
High Speed Machining ◽  
Machined Surface ◽  
Stamping Die

: Cr12MoV hardened steel is widely used in the manufacturing of stamping die because of its high strength, high hardness, and good wear resistance. As a kind of mainstream cutting technology, high-speed machining has been applied in the machining of Cr12MoV hardened steel. Based on the review of a large number of literature, the development of high-speed machining of Cr12MoV hardened steel was summarized, including the research status of the saw-tooth chip, cutting force, cutting temperature, tool wear, machined surface quality, and parameters optimization. The problems that exist in the current research were discussed and the directions of future research were pointed out. It can promote the development of high-speed machining of Cr12MoV hardened steel.

Review of Research on Hydrostatic Bearings

2020 ◽  
Vol 13 ◽  
Author(s):  
Xiaodong Yu ◽  
Yu Wang ◽  
Junfeng Wang ◽  
Wenkai Zhou ◽  
Hongwei Bi ◽  
...  
Keyword(s):  
High Speed ◽  
Static Pressure ◽  
Development Trend ◽  
Cnc Machining ◽  
Pressure Effects ◽  
Cnc Machine Tools ◽  
Future Research ◽  
Theoretical Formula ◽  
Hydrostatic Bearing ◽  
Hydrostatic Bearings

Background: Hydrostatic bearings have the advantages of strong bearing capacity, good stability, small friction coefficient and long life. The performance of liquid hydrostatic bearings directly affect the accuracy and efficiency of CNC machining equipment. The performance is conducive to the development of CNC machine tools towards high speed and heavy load, so it is necessary to sort out and summarize the existing research results. Objective: This study summarizes the current development status of hydrostatic bearings and explains the development trend of hydrostatic bearings. Methods: According to the recently published journal articles and patents, the recent experimental research on hydrostatic thrust bearings is summarized. This paper summarizes many factors that affect the performance of hydrostatic bearings, and discusses the causes of various factors on hydrostatic bearings. Finally, future research on hydrostatic bearings is presented. Results: The study discusses experimental methods, simulation processes, and experimental results. Conclusion: This study can produce dynamic and static pressure effects by changing the structure of the oil cavity of the hydrostatic bearing. This effect can make up for the static pressure loss. By improving the theoretical formula and mathematical model and proposing a new simulation method, the accuracy of the hydrostatic bearing simulation is satisfied; the future development trend of the hydrostatic bearing is proposed.

scholarly journals 1.5 °C degrowth scenarios suggest the need for new mitigation pathways

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lorenz T. Keyßer ◽  
Manfred Lenzen
Keyword(s):  
Technological Change ◽  
High Speed ◽  
Large Scale ◽  
High Energy ◽  
Climate Mitigation ◽  
Intergovernmental Panel ◽  
Economic Output ◽  
Integrated Assessment Modelling ◽  
Negative Emissions ◽  
Energy Emissions

Abstract1.5  °C scenarios reported by the Intergovernmental Panel on Climate Change (IPCC) rely on combinations of controversial negative emissions and unprecedented technological change, while assuming continued growth in gross domestic product (GDP). Thus far, the integrated assessment modelling community and the IPCC have neglected to consider degrowth scenarios, where economic output declines due to stringent climate mitigation. Hence, their potential to avoid reliance on negative emissions and speculative rates of technological change remains unexplored. As a first step to address this gap, this paper compares 1.5  °C degrowth scenarios with IPCC archetype scenarios, using a simplified quantitative representation of the fuel-energy-emissions nexus. Here we find that the degrowth scenarios minimize many key risks for feasibility and sustainability compared to technology-driven pathways, such as the reliance on high energy-GDP decoupling, large-scale carbon dioxide removal and large-scale and high-speed renewable energy transformation. However, substantial challenges remain regarding political feasibility. Nevertheless, degrowth pathways should be thoroughly considered.

scholarly journals A comprehensive review of the influences of nanoparticles as a fuel additive in an internal combustion engine (ICE)

2020 ◽  
Vol 9 (1) ◽  
pp. 1326-1349
Author(s):  
Siti Nurul Akmal Yusof ◽  
Nor Azwadi Che Sidik ◽  
Yutaka Asako ◽  
Wan Mohd. Arif Aziz Japar ◽  
Saiful Bahri Mohamed ◽  
...  
Keyword(s):  
Combustion Engine ◽  
Wide Spectrum ◽  
High Energy ◽  
Combustion Efficiency ◽  
Fuel Properties ◽  
Future Research ◽  
Biodiesel Fuel ◽  
Fuel Additive ◽  
Engine Combustion ◽  
Research Findings

Abstract Nanofluid is a colloidal mixture consisting of nano-sized particles dispersed in a liquid medium. It improves heat transfer properties and promotes high energy efficiency in a wide spectrum of engineering applications. In recent years, particularly in the automotive industry, the addition of nanofluid in diesel/biodiesel as an additive for ICE has become an attractive approach to promote enhanced combustion efficiency and emission reduction due to their superior thermophysical properties. Many researchers have previously demonstrated that the addition of nanoparticles in diesel/biodiesel fuel improved the overall engine combustion characteristics. As a whole, this study aims to summarize the recent research findings related to the effect of nanoparticles on the fuel properties and engine combustion efficiency. Furthermore, different types of additive blended with varying fuel properties are also compared and discussed. Lastly, the advantages and prospects of using nanofluid as an additive fuel are summarized for future research opportunities.

scholarly journals Combustion Thermodynamics of Ethanol, n-Heptane, and n-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2729
Author(s):  
Ireneusz Pielecha ◽  
Sławomir Wierzbicki ◽  
Maciej Sidorowicz ◽  
Dariusz Pietras
Keyword(s):  
Heat Release ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Direct Injection ◽  
Combustion Process ◽  
Combustion Efficiency ◽  
Injection System ◽  
Rapid Compression Machine ◽  
Process Indicators ◽  
Rapid Compression

The development of internal combustion engines involves various new solutions, one of which is the use of dual-fuel systems. The diversity of technological solutions being developed determines the efficiency of such systems, as well as the possibility of reducing the emission of carbon dioxide and exhaust components into the atmosphere. An innovative double direct injection system was used as a method for forming a mixture in the combustion chamber. The tests were carried out with the use of gasoline, ethanol, n-heptane, and n-butanol during combustion in a model test engine—the rapid compression machine (RCM). The analyzed combustion process indicators included the cylinder pressure, pressure increase rate, heat release rate, and heat release value. Optical tests of the combustion process made it possible to analyze the flame development in the observed area of the combustion chamber. The conducted research and analyses resulted in the observation that it is possible to control the excess air ratio in the direct vicinity of the spark plug just before ignition. Such possibilities occur as a result of the properties of the injected fuels, which include different amounts of air required for their stoichiometric combustion. The studies of the combustion process have shown that the combustible mixtures consisting of gasoline with another fuel are characterized by greater combustion efficiency than the mixtures composed of only a single fuel type, and that the influence of the type of fuel used is significant for the combustion process and its indicator values.

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