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Book Lean Burn Natural Gas Engine R D

Download or read book Lean Burn Natural Gas Engine R D written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of this cooperative research is to develop and verify models of internal combustion engine spark ignition devices in order to improve combustion chamber fuel ignition characteristics and to improve spark plug durability. As a direct result of this joint research, a novel spark plug design was improved. A theory of spark arc motion was developed that explains experimentally observed effects not explained by other published theories. The knowledge developed by this research will be used to further improve spark plugs as well as improve the ignition process in a combustion chamber. The predictive models developed here are compared with experimental measurements, including high-speed photographs, of the spark as it translates across the gap. Two different spark plug configurations were investigated: the conventional or J-gap plug, and a novel spark ignition device (the FANG plug) invented by Cummins, Inc., the CRADA partner. A description of the physics of arc dynamic motion in a spark plug gap, including the effects of an imposed transverse magnetic field, appears here in Appendix A as a result of the analytical effort. The theory proposed here does explain experimentally observed effects not completely explained by other research publications appearing in the scientific literature. These effects are due to pressure and ion, electron, and electrode interactions. A dominant mechanism for electrode erosion is presented for both spark plug configurations. Reversing the polarity of both types of spark plugs has verified this proposed erosion mechanism, according to data collected at Cummins. An extensive series of experiments measured the arc position, voltage, and current as a function of time during the approximately 2 millisecond spark discharge. FANG plug data, obtained with the fast-framing camera experimental apparatus operating at 200,000 frames per second, are presented that show the transverse arc velocity varying directly as the inverse square root of the elapsed time since arc initiation. At the request of Cummins, experiments were performed on three conventional spark plugs identical in design and having the same spark gap, but differing as follows: one was new, another had been used in an engine, and the third was new but had been sandblasted to simulate a used plug. Cummins had observed that only the used plug required a significantly higher breakdown voltage. Experiments at ORNL indicated that the used plug had a significantly higher breakdown voltage confirming the Cummins observations (although the sandblasted plug also exhibited a higher breakdown voltage than the new plug but lower than the used plug), and thus an apparent increase of the arc breakdown voltage results as the plug ages in use. Further analysis of this phenomenon is warranted.

Book Ignition Systems for Gasoline Engines

Download or read book Ignition Systems for Gasoline Engines written by Michael Günther and published by Springer. This book was released on 2016-11-18 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: The volume includes selected and reviewed papers from the 3rd Conference on Ignition Systems for Gasoline Engines in Berlin in November 2016. Experts from industry and universities discuss in their papers the challenges to ignition systems in providing reliable, precise ignition in the light of a wide spread in mixture quality, high exhaust gas recirculation rates and high cylinder pressures. Classic spark plug ignition as well as alternative ignition systems are assessed, the ignition system being one of the key technologies to further optimizing the gasoline engine.

Book Laser Ignition of Internal Combustion Engines

Download or read book Laser Ignition of Internal Combustion Engines written by Martin Weinrotter and published by GRIN Verlag. This book was released on 2011-04 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Doctoral Thesis / Dissertation from the year 2006 in the subject Electrotechnology, grade: 1, mit Ausgezeichnung bestanden, Vienna University of Technology (Insitut für Photonik), language: English, abstract: In this PhD thesis different fundamental aspects and the practical usability of a laser ignition system as a new, innovative and alternative ignition approach for internal combustion engines were investigated in great detail mainly experimentally. Ignition experiments in combustion chambers under high pressures and elevated temperatures have been conducted. Different fuels were investigated. Also the minimum breakdown energy in dependence of the initial temperature and pressure with the help of an aspheric lens with a high numerical aperture was studied. High-speed Schlieren diagnostics have been conducted in the combustion chamber. The different stages like the ignition plasma within the first nanoseconds via the shock wave generation to the expanding flame kernel were investigated. With the help of multi-point ignition the combustion duration could be reduced significantly. The controlled start of auto-ignition of n-heptane-air mixtures by resonant absorption of Er, Cr: YSGG laser radiation at 2.78 μm by additionally introduced water has been proven in combustion chamber experiments as a completely new idea. Beside experiments in the combustion chambers and long term tests under atmospheric conditions, various tests in SI engines up to 200 h, have been made. Different sources of contamination of the window surface have been identified. First experiments with a longitudinally diode-pumped, fiber-coupled and passively Q-switched solid-state laser α-prototype system with maximum pulse energy of 1.5 mJ at about 1.5 ns pulse duration were performed which allowed to ignite the engine successfully over a test period of 100 h. In cooperation with Lund University in Sweden, experiments have been performed on another engine test bed running in HCCI mode revealing the las

Book Natural Gas Engines

Download or read book Natural Gas Engines written by Kalyan Kumar Srinivasan and published by Springer. This book was released on 2018-11-03 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the various advanced reciprocating combustion engine technologies that utilize natural gas and alternative fuels for transportation and power generation applications. It is divided into three major sections consisting of both fundamental and applied technologies to identify (but not limited to) clean, high-efficiency opportunities with natural gas fueling that have been developed through experimental protocols, numerical and high-performance computational simulations, and zero-dimensional, multizone combustion simulations. Particular emphasis is placed on statutes to monitor fine particulate emissions from tailpipe of engines operating on natural gas and alternative fuels.

Book Selective NOx Recirculation for Stationary Lean Burn Natural Gas Engines

Download or read book Selective NOx Recirculation for Stationary Lean Burn Natural Gas Engines written by Nigel N. Clark and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitric oxide (NO) and nitrogen dioxide (NO2) generated by internal combustion (IC) engines are implicated in adverse environmental and health effects. Even though lean-burn natural gas engines have traditionally emitted lower oxides of nitrogen (NOx) emissions compared to their diesel counterparts, natural gas engines are being further challenged to reduce NOx emissions to 0.1 g/bhp-hr. The Selective NOx Recirculation (SNR) approach for NOx reduction involves cooling the engine exhaust gas and then adsorbing the NOx from the exhaust stream, followed by the periodic desorption of NOx. By sending the desorbed NOx back into the intake and through the engine, a percentage of the NOx can be decomposed during the combustion process. SNR technology has the support of the Department of Energy (DOE), under the Advanced Reciprocating Engine Systems (ARES) program to reduce NOx emissions to under 0.1 g/bhp-hr from stationary natural gas engines by 2010. The NO decomposition phenomenon was studied using two Cummins L10G natural gas fueled spark-ignited (SI) engines in three experimental campaigns. It was observed that the air/fuel ratio ({lambda}), injected NO quantity, added exhaust gas recirculation (EGR) percentage, and engine operating points affected NOx decomposition rates within the engine. Chemical kinetic model predictions using the software package CHEMKIN were performed to relate the experimental data with established rate and equilibrium models. The model was used to predict NO decomposition during lean-burn, stoichiometric burn, and slightly rich-burn cases with added EGR. NOx decomposition rates were estimated from the model to be from 35 to 42% for the lean-burn cases and from 50 to 70% for the rich-burn cases. The modeling results provided an insight as to how to maximize NOx decomposition rates for the experimental engine. Results from this experiment along with chemical kinetic modeling solutions prompted the investigation of rich-burn operating conditions, with added EGR to prevent preignition. It was observed that the relative air/fuel ratio, injected NO quantity, added EGR fraction, and engine operating points affected the NO decomposition rates. While operating under these modified conditions, the highest NO decomposition rate of 92% was observed. In-cylinder pressure data gathered during the experiments showed minimum deviation from peak pressure as a result of NO injections into the engine. A NOx adsorption system, from Sorbent Technologies, Inc., was integrated with the Cummins engine, comprised a NOx adsorbent chamber, heat exchanger, demister, and a hot air blower. Data were gathered to show the possibility of NOx adsorption from the engine exhaust, and desorption of NOx from the sorbent material. In order to quantify the NOx adsorption/desorption characteristics of the sorbent material, a benchtop adsorption system was constructed. The temperature of this apparatus was controlled while data were gathered on the characteristics of the sorbent material for development of a system model. A simplified linear driving force model was developed to predict NOx adsorption into the sorbent material as cooled exhaust passed over fresh sorbent material. A mass heat transfer analysis was conducted to analyze the possibility of using hot exhaust gas for the desorption process. It was found in the adsorption studies, and through literature review, that NO adsorption was poor when the carrier gas was nitrogen, but that NO in the presence of oxygen was adsorbed at levels exceeding 1% by mass of the sorbent. From the three experimental campaigns, chemical kinetic modeling analysis, and the scaled benchtop NOx adsorption system, an overall SNR system model was developed. An economic analysis was completed, and showed that the system was impractical in cost for small engines, but that economies of scale favored the technology.

Book Experimental Investigation of Advanced Ignition Systems for High Efficiency Combustion

Download or read book Experimental Investigation of Advanced Ignition Systems for High Efficiency Combustion written by Bader Almansour and published by . This book was released on 2018 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the second part of this dissertation, a spherical chamber was designed and validated to measure the laminar burning velocity (LBV) of a promising biofuel: 2,4-Dimethyl-3-pentanone, (DIPK), for homogenous charge compression ignition engines. LBV measurements were carried out with various diluent species (N2, Ar, and He) in order to provide several data points for development and validation of DIPK chemical kinetic mechanisms. It has been found that DIPK does not only have higher temperature and pressure sensitivities (compared to iso-octane), but additionally enabled a faster laminar burning velocity which leads to higher rate of heat release in reciprocating engines.

Book An Experimental Investigation of Ignition and Combustion Phenomena in Pilot ignited Natural Gas Engines

Download or read book An Experimental Investigation of Ignition and Combustion Phenomena in Pilot ignited Natural Gas Engines written by Kalyan Kumar Srinivasan and published by . This book was released on 2006 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasingly stringent emissions statutes and the need for energy security and self-sufficiency are primary driving factors to consider alternatives to fossil fuels. In this regard pilot-ignited natural gas engines are clean, efficient, economical, and thereby, viable alternatives to diesel engines.

Book Fundamental Studies of Ignition Process in Large Natural Gas Engines Using Laser Spark Ignition

Download or read book Fundamental Studies of Ignition Process in Large Natural Gas Engines Using Laser Spark Ignition written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Past research has shown that laser ignition provides a potential means to reduce emissions and improve engine efficiency of gas-fired engines to meet longer-term DOE ARES (Advanced Reciprocating Engine Systems) targets. Despite the potential advantages of laser ignition, the technology is not seeing practical or commercial use. A major impediment in this regard has been the 'open-path' beam delivery used in much of the past research. This mode of delivery is not considered industrially practical owing to safety factors, as well as susceptibility to vibrations, thermal effects etc. The overall goal of our project has been to develop technologies and approaches for practical laser ignition systems. To this end, we are pursuing fiber optically coupled laser ignition system and multiplexing methods for multiple cylinder engine operation. This report summarizes our progress in this regard. A partial summary of our progress includes: development of a figure of merit to guide fiber selection, identification of hollow-core fibers as a potential means of fiber delivery, demonstration of bench-top sparking through hollow-core fibers, single-cylinder engine operation with fiber delivered laser ignition, demonstration of bench-top multiplexing, dual-cylinder engine operation via multiplexed fiber delivered laser ignition, and sparking with fiber lasers. To the best of our knowledge, each of these accomplishments was a first.

Book Advanced Natural Gas Reciprocating Engine s

Download or read book Advanced Natural Gas Reciprocating Engine s written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy independence and fuel savings are hallmarks of the nation's energy strategy. The advancement of natural gas reciprocating engine power generation technology is critical to the nation's future. A new engine platform that meets the efficiency, emissions, fuel flexibility, cost and reliability/maintainability targets will enable American manufacturers to have highly competitive products that provide substantial environmental and economic benefits in the US and in international markets. Along with Cummins and Waukesha, Caterpillar participated in a multiyear cooperative agreement with the Department of Energy to create a 50% efficiency natural gas powered reciprocating engine system with a 95% reduction in NOx emissions by the year 2013. This platform developed under this agreement will be a significant contributor to the US energy strategy and will enable gas engine technology to remain a highly competitive choice, meeting customer cost of electricity targets, and regulatory environmental standard. Engine development under the Advanced Reciprocating Engine System (ARES) program was divided into phases, with the ultimate goal being approached in a series of incremental steps. This incremental approach would promote the commercialization of ARES technologies as soon as they emerged from development and would provide a technical and commercial foundation of later-developing technologies. Demonstrations of the Phase I and Phase II technology were completed in 2004 and 2008, respectively. Program tasks in Phase III included component and system development and testing from 2009-2012. Two advanced ignition technology evaluations were investigated under the ARES program: laser ignition and distributed ignition (DIGN). In collaboration with Colorado State University (CSU), a laser ignition system was developed to provide ignition at lean burn and high boost conditions. Much work has been performed in Caterpillar's DIGN program under the ARES program. This work has consisted of both modeling and single cylinder engine experiments to quantify DIGN performance. The air handling systems of natural gas engines dissipate a percentage of available energy as a result of both flow losses and turbomachinery inefficiencies. An analytical study was initiated to increase compressor efficiency by employing a 2-stage inter-cooled compressor. Caterpillar also studied a turbo-compound system that employs a power turbine to recover energy from the exhaust gases for improved engine efficiency. Several other component and system investigations were undertaken during the final phase of the program to reach the ultimate ARES goals. An intake valve actuation system was developed and tested to improve engine efficiency, durability and load acceptance. Analytical modeling and materials testing were performed to evaluate the performance of steel pistons and compacted graphite iron cylinder head. Effort was made to improve the detonation sensing system by studying and comparing the performance of different pressure sensors. To reduce unburned hydrocarbon emissions, different camshafts were designed and built to investigate the effect of exhaust valve opening timing and value overlap. 1-D & 3-D coupled simulation was used to study intake and exhaust manifold dynamics with the goal of reducing load in-balance between cylinders. Selective catalytic reduction with on-board reductant generation to reduce NOx emissions was also engine tested. An effective mean to successfully deploy ARES technologies into the energy markets is to deploy demonstration projects in the field. In 2010, NETL and Caterpillar agreed to include a new "opportunity fuel" deliverable and two field demonstrations in the ARES program. An Organic Rankine Cycle system was designed with production intent incorporating lessons learned from the Phase II demonstration. Unfortunately, business conditions caused Caterpillar to cancel this demonstration in 2011. Nonetheless, Caterpillar partnered w ...

Book Ignition Systems for Lean burn Gas Engines

Download or read book Ignition Systems for Lean burn Gas Engines written by Nicholas C. Pashley and published by . This book was released on 1997 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.