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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

A study of the dynamic instabilities of the apex seal and the chatter phenomena in Wankel rotary engines

Besorak, Yavuz. January 1975 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 141-147).

Altering the volumetric expansion ratio of a Lysholm helical screw expander

Dunbar, Michael K. January 1984 (has links)
Thesis (masters) -- University of California, Berkeley. / DOE contract no.: AT03-80ET27252. Includes bibliographical references. Also available on the Internet.

Wu: A Cultural Export Game with Dynamic Difficulty

Yang, Yunjie 15 May 2020 (has links)
This report discusses the design and development of Wu, a 2D action game intended to serve as a means for exporting Chinese popular culture to Western players. Developed with the Unity engine, the game features a dynamic difficulty system that monitors player behavior and automatically modifies the content to better match the observed level of skill. Feedback from playtesting confirmed that the dynamic difficulty adjustment significantly increased the probability of completing the game, and that most players acquired a better understanding of the Wuxia genre on which the game is based.

Investigation of diesel-ethanol and diesel-gasoline dual fuel combustion in a single cylinder optical diesel engine

Mirmohammadsadeghi, Mahmoudreza January 2018 (has links)
Ever growing population and increased energy consumption across all industries has resulted in higher atmospheric concentration of the greenhouse gases (GHG) and therefore an increase in the planet's average temperature, which has led to increasingly demanding and more strict legislations on pollutant sources, and more specifically, the automotive industry. As a consequence of all this, the demand for research into alternative energy sources has greatly increased. In this study combustion characteristics, engine performance, and exhaust emission of diesel-ethanol and diesel-gasoline are investigated in an optical direct injection diesel engine. In particular, effects of different substitution ratios and diesel injection strategies are studied when the total fuel energy is kept constant. The three main substitution ratios used in this study include 45% (45% of fuel energy from port-injected ethanol/gasoline and 55% from direct injection diesel), 60%, and 75%. The engine used for this investigation is a Ricardo Hydra single cylinder optical engine running at 1200 rpm. In-cylinder pressure measurement is used for calculating all engine parameters, heat release rate, and efficiency. In addition to the thermodynamic analysis of the combustion parameters, high speed camera was used alongside with a copper vapor laser or the high speed image intensifier in the high speed video imaging for the optical analysis of the effect of the above-mentioned parameters on autoignition and combustion processes, while Horiba particulate analyser and AVL smoke meter were utilized in monitoring and recording emissions for every tested condition. Depending on the testing conditions, such as injection strategy and intake conditions, both dual-fuel operations were able to deliver high efficiency and improved emissions compared to that of a pure diesel engine operation, with the diesel-gasoline operation offering more consistency in improved thermal efficiency, and the diesel-ethanol operation delivering lower emission output. The optical analysis of the combustion represents the main difference in the flame propagation, distribution and quality for each substitute fuel and its substitution percentage, as well as the condition under examination.

Use of an Engine Cycle Simulation to Study a Biodiesel Fueled Engine

Zheng, Junnian 14 January 2010 (has links)
Based on the GT-Power software, an engine cycle simulation for a biodiesel fueled direct injection compression ignition engine was developed and used to study its performance and emission characteristics. The major objectives were to establish the engine model for simulation and then apply the model to study the biodiesel fueled engine and compare it to a petroleum-fueled engine. The engine model was developed corresponding to a 4.5 liter, John Deere 4045 four-cylinder diesel engine. Submodels for flow in intake/exhaust system, fuel injection, fuel vaporization and combustion, cylinder heat transfer, and energy transfer in a turbocharging system were combined with a thermodynamic analysis of the engine to yield instantaneous in-cylinder parameters and overall engine performance and emission characteristics. At selected engine operating conditions, sensitivities of engine performance and emission on engine load/speed, injection timing, injection pressure, EGR level, and compression ratio were investigated. Variations in cylinder pressure, ignition delay, bsfc, and indicated specific nitrogen dioxide were determined for both a biodiesel fueled engine and a conventional diesel fueled engine. Cylinder pressure and indicated specific nitrogen dioxide for a diesel fueled engine were consistently higher than those for a biodiesel fueled engine, while ignition delay and bsfc had opposite trends. In addition, numerical study focusing on NOx emission were also investigated by using 5 different NO kinetics. Differences in NOx prediction between kinetics ranged from 10% to 65%.

V2500 aero engine repair capability optimization

Fairhurst, George Teo Jee Tye January 2013 (has links)
The Christchurch Engine Centre (CHCEC) provides maintenance, repair and overhaul services for the IAE V2500 commercial jet engine. CHCEC is being driven to reduce engine shop visit (ESV) prices to satisfy customer demand and offer competitive prices. The reduction in ESV price is reducing profit margins and internal cost reduction is not a sustainable solution. Historical repair ESV data was reviewed and analyzed to identify major cost drivers and opportunities for overall shop visit cost reduction. It was found that CHCEC can reduce ESV prices through introducing recommended third party repairs which increases the savings to the customer and should allow CHCEC to secure more engines from customers.

The study of Competency Analysis for manufacturing engineer Professionals of Aero Engine Industry

Lin, Shiou-Lan 27 June 2005 (has links)
The purpose of this research is to construct the competency of engine manufacturing engineer of Aero engine industry. Base on the result, it is expected to provide the principles for the Aero engine industry for personnel recruitment, education and training, and effectively enhance the working effciency. At first, this research figures out the research items of related competency analysis base on the different literatures. And then through deep discussion with senior engineers, management staffs and experts, to determine the key purpose of engine manufacturing engineers of Aero engine industry, i.e. to execute feasibility evaluation, process design, engineering integration, tool design and problem solving, etc. From those key purposes, it developped 6 major functions, 24 minor functions and 94 function units. For further study of the function tree of those competency, this research also conduct the weighing questionaire from some experts, to evaluate the weighing value of different functions on the tree diagram, to decide the degree of different functions. Among the 6 major functions, the weight of process integration capability is the highest, engineering capability get the second one, both of these two capabilities occupied 59% of the total weight. Besides these two important capabilities, it is followed by general process capability, special process capability, common capability, and operating of CAD. As a result, process integration capability and engineering competency are the most important capabilities for engine manufacturing engineers. This result could be the reference for personnel cultivation of aviation industry and also to provide the indications for self-assessment and self-growth of engine manufacturing engineers. The ultimate purpose is to expect the promotion of engine manufacturing of national Aero engine industry.

Hardware Design and Verification of Clipping Algorithms in 3D Graphics Geometry Engine

Tien, Tzu-Ching 04 September 2008 (has links)
A 3D graphics system usually consists of two major subsystems: geometry subsystem and rendering subsystem. The geometry subsystem performs transformation, lighting, backface culling, and clipping. The clipping is to remove the part of a triangle that is outside of the view volume by calculating the intersections of the triangle edges with view planes. The clipping operation turns out to be a time-consuming procedure in the geometry subsystem. In this thesis, we present several clipping algorithms and their hardware implementations, and compare the performance in the geometry subsystem. Furthermore, a new pre-clipping algorithm is also proposed to reduce the number of triangles that need to go through the clipping operations in order to reduce the burden of clipping operations in the whole geometry subsystem. The whole geometry system including the pre-clipping and clipping hardware is verified in a complete 3G graphics system in the Versatile FPGA demonstration board.

The Production of Power by Pure Rotary Means

Hudson, Barry, not given January 2008 (has links)
The chapters subsequent to the design discussion describe the evolution of the project. During the progression of the project, four case studies were undertaken. Each of these case studies involved the design of an engine, using the principles expounded in the early chapters. The parts of three of these were manufactured. The project has culminated in case study four which consisted of the conception, design and component manufacture of a new type of engine: the Hudson 5 Cycle Rotary Engine. It does not reciprocate, nor is it orbital (Sarich) and is not peritrocoidal (Mazda). It operates with pure rotary motion. It also promises to have a favourable environmental aspect due to its excellent fuel efficiency and because of its exceptional power to weight and power to size ratios plus a low component count. The small size and low number of parts make it very economical to produce, both in materials and energy.

The design and development of a rotary stirling cycle engine.

Rosenegger, Lothar W. January 1973 (has links)
No description available.

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