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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.
191

Applying Artificial Neural Networks to Engines

Giraldo Delgado, Juan Camilo 23 March 2022 (has links)
Internal combustion engines, used for light duty transportation, represent a major role in mobility, contributing 28.6% to CO$_2$ emissions worldwide. To mitigate environmental impact and ease the transition to clean technologies, the search for more efficient, less polluting engines has been demanded, and unique tools are necessary to meet the constantly upgraded policies. Hence, data-driven approaches that emulate current vehicles represent a valuable contribution to the improvement of engine performance. Dynamometer tests of commercial engines are open-data, and a dependable source for understanding on-road behavior of several vehicle variables. Artificial neural network (ANN) algorithms, a subset of machine learning, have received considerable attention recently given their wide number of applications and the possibility to provide accurate data-driven approximations. This work describes a methodology for applying ANN’s to predict emissions, efficiency, and fuel consumption in combustion engines using dynamometer test data, and to extrapolate its use in new technologies. The procedure is also applied to a hybrid vehicle case study. The proposed methodology accurately generates ANN’s for the prediction of brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and emissions in conventional engines with 𝑅$^2$>0.91 and mean absolute errors (MAE) of less than five percent. Using the same approach, the hybrid vehicle state of charge (SOC), and the fuel scale state, are predicted, showing good agreement 𝑅$^2$>0.96 and confirming the versatility of the proposed algorithm. Finally, an initial approach for dealing with missing data in the databases is introduced. Using various simple and iterative imputation methods, it was possible to obtain 𝑅$^2$>0.80 for predicting the BTE and BSFC with five percent of the data missing from the input values.
192

Development of a parametric analysis microcomputer model for evaluating the thermodynamic performance of a reciprocating Brayton cycle engine

White, Thomas J. 01 January 1987 (has links)
In this thesis, applicable data from research on IC engines have been adapted to PACE engine designs. Data from studies on heat transfer, friction, and pressure losses, in particular, have been used. Certain parameters which define operation and design characteristics appear to influence PACE engine performance very strongly. Some of the more critical parameters, notably friction and heat transfer coefficients, must be determined experimentally if accurate model results are to be expected. Pressure ratio, compressor RPM, and maximum combustor temperature, the independent operating parameters, also have a dramatic effect on engine performance. Other design or operating characteristics and working fluid properties are not controlled independently. These are dictated by the engine physical design configuration and operation, ambient conditions, and choice of fuel.
193

The gas chromatographic study of the cool flame and motored engine combustion of some hydrocarbons /

Menapace, Henry Robert January 1958 (has links)
No description available.
194

The possibility of increasing compression ratios by using water as an anti-detonant

Haines, Raymond G. 07 July 2010 (has links)
Conclusions (1) Water 1s a knock suppressor. (2) Water does not act as an anti-detonant by slowing down the rate of flame propagation, but merely removes a portion of the heat of combustion. (3) Increasing the compression ratio requires a decrease in spark advance. / Master of Science
195

Studies of combustion and crevice gas motion in a flow-visualization spark-ignition engine

Namazian, Mehdi January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Mehdi Namazian. / Ph.D.
196

Effects of fuel blends containing Croton oil, Butanol and Diesel on the performance and emissions of Diesel engines.

Lujaji, Frank. January 2010 (has links)
M. Tech. Mechanical Engineering. / Evaluates the effects of blends (vegetable oil-Butanol (BU) alcohol-diesel) on fuel properties, engine performance, combustion, and emission characteristics. Fuel blends investigated were croton oil (CRO), Diesel (D2), 20% CRO-80% D2, 15% CRO-5% BU-80% D2 and 10% CRO-10% BU-80% D2.
197

Tradeoff between internal combustion engined vehicles and electric vehicles in Hong Kong /

Chan, Sau-ha. January 1995 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references (leaf [110-114]).
198

Development Of An Advanced Methodology For Automotive IC Engine Design Optimization Using A Multi-Physics CAE Approach

Sehemby, Amardeep A Singh 09 1900 (has links) (PDF)
The internal combustion engine is synonyms with the automobile since its invention in late 19th century. The internal combustion engine today is far more advanced and efficient compared to its early predecessors. An intense competition exists today amongst the automotive OEMs in various countries and regions for stepping up sales and increasing market share. The pressure on automotive OEMs to reduce fuel consumption and emission is enormous which has lead to innovations of many variations in engine and engine-related technologies. However, IC engines are in existence for well more than a century and hence have already evolved to a highly refined state. Changes in IC engine are therefore largely incremental in nature. A deterrent towards development of an engine configuration that is significantly different from its predecessor is the phenomenal cost involved in prototyping. Thus, the only viable alternative in exploring new engine concepts and even optimizing designs currently in operation is through extensive use of CAE. In light of published work in the field of analysis of IC engines, current research effort is directed towards development of a rational methodology for arriving at a weight-optimized engine design, which simultaneously meets performance of various attributes such as thermal, durability, vehicle dynamics and NVH. This is in contrast to the current methodology adopted in industry, according to which separate teams work on aspects of engine design such as combustion, NVH (Noise, Vibration and Harshness), acoustics, dynamics, heat transfer and durability. Because of the involvement of heterogeneous product development groups, optimization of an engine for weight, which can have a significant impact on its power-to-weight ratio, becomes a slow process beset with manual interventions and compromise solutions. Thus, following the traditional approach, it is quite difficult to claim that an unambiguous weight-optimized design has been achieved. As a departure from the practiced approach, the present research effort is directed at the deployment of a single multi-physics explicit analysis solver, viz. LS-DYNA - generally known for its contact-impact analysis capabilities, for simultaneously evaluating a given engine design for heat transfer, mechanical and thermal loading, and vibration. It may be mentioned that only combustion analysis is carried out in an uncoupled manner, using proven phenomenological thermodynamic relations, to initially arrive at mechanical and thermal loading/boundary conditions for the coupled thermo-mechanical analysis. The proposed methodology can thus be termed as a semi-integrated technique and its efficacy is established with the case study of designing a single cylinder air-cooled diesel engine from scratch and its optimization.
199

Influência das forças de inércia e do balanceador de massas na dinâmica do motor de combustão interna / Influence of inertia forces and mass balancer on internal combustion engine dynamics

Selim, André Baroni 16 August 2018 (has links)
Orientador: Airton Nabarrete / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T19:07:22Z (GMT). No. of bitstreams: 1 Selim_AndreBaroni_M.pdf: 8247651 bytes, checksum: 306a914d67d3207fb1d8f193b3bf7bd2 (MD5) Previous issue date: 2010 / Resumo: Este trabalho visa estudar a influência do balanceador de massas e das forças de inércia dos componentes internos móveis do motor na dinâmica do motor de combustão interna apoiado sobre amortecedores de vibrações. Para o estudo da influência do balanceador de massas, diversas análises experimentais foram realizadas com um motor em dinamômetro. Chegam-se nas conclusões através da comparação dos deslocamentos medidos do motor com e sem balanceador de massas. Para que a influência das forças de inércia dos componentes internos móveis do motor fosse estudada, um modelo matemático foi criado. Neste modelo consideram-se as forças vindas dos componentes internos móveis atuando em um corpo rígido, neste caso o bloco do motor, apoiado sobre quatro amortecedores de vibrações com seis graus de liberdade. Variam-se dados construtivos como massas e geometria dos componentes internos móveis do motor observando a sua influência sobre o comportamento dinâmico do motor de combustão interna. A validação deste modelo matemático ocorre por meio da comparação de seus resultados com os resultados reais observados nas análises experimentais / Abstract: This work aims at studying the influence of mass balancer and inertia forces coming from engine internal components on internal combustion engine dynamics supported by vibration dampers. For mass balancer study several experimental analyses were performed with a dynamometer. The conclusions are obtained by comparison between measured engine displacements with and without mass balancer. To study the influence of inertia forces from engine internal components, a mathematical model was developed. In this model the inertia forces act on a rigid body, the engine crankcase, supported by four vibration dampers and with six degrees of freedom. Some modifications are made on engine internal components such as mass and geometry observing what is their influence on internal combustion engine dynamics. The mathematical model is validated by comparison against experimental analyses / Mestrado / Dinâmica / Mestre em Engenharia Automobilistica
200

Conceptual design of a commercial-Tokamak-hybrid-reactor fueling system

Matney, Kenneth Dale, Commercial Tokamak Hybrid Reactor. January 2011 (has links)
Digitized by Kansas Correctional Industries

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