Relevant bibliographies by topics / Large bore gas engine

Academic literature on the topic 'Large bore gas engine'

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Published: 14 March 2023

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Journal articles on the topic "Large bore gas engine"

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Schaub, F. S., and R. L. Hubbard. "A Procedure for Calculating Fuel Gas Blend Knock Rating for Large-Bore Gas Engines and Predicting Engine Operation." Journal of Engineering for Gas Turbines and Power 107, no. 4 (October 1, 1985): 922–30. http://dx.doi.org/10.1115/1.3239837.

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This paper describes the procedure developed by Cooper-Bessemer for large-bore gas engines to calculate the knock rating of gas fuel blends and to predict with accuracy the required engine build to use that fuel with optimum detonation margin. Engine prototype test work has included fuel sensitivity tests mapped as a function of compression ratio, fuel air ratio, ignition advance, combustion air temperature, and engine rating. Success in predicting production engine operation for a given application involving a particular fuel blend has been gratifying. The basic reference method blend selected was normal butane in methane. Details are included in the paper to illustrate the problems in making sensitivity correlations between small-bore fuel research engines and large-bore production engines.
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Olsen, D. B., J. C. Holden, G. C. Hutcherson, and B. D. Willson. "Formaldehyde Characterization Utilizing In-Cylinder Sampling in a Large Bore Natural Gas Engine." Journal of Engineering for Gas Turbines and Power 123, no. 3 (December 7, 2000): 669–76. http://dx.doi.org/10.1115/1.1363601.

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This research addresses the growing need to better understand the mechanisms through which engine-out formaldehyde is formed in two-stroke cycle large bore natural gas engines. The investigation is performed using a number of different in-cylinder sampling techniques implemented on a Cooper-Bessemer GMV-4TF four-cylinder two-stroke cycle large bore natural gas engine with a 36-cm (14-in.) bore and a 36-cm (14-in.) stroke. The development and application of various in-cylinder sampling techniques is described. Three different types of valves are utilized, (1) a large sample valve for extracting a significant fraction of the cylinder mass, (2) a fast sample valve for crank angle resolution, and (3) check valves. Formaldehyde in-cylinder sampling data are presented that show formaldehyde mole fractions at different times during the engine cycle and at different locations in the engine cylinder. The test results indicate that the latter part of the expansion process is a critical time for engine-out formaldehyde formation. The data show that significant levels of formaldehyde form during piston and end-gas compression. Additionally, formaldehyde is measured during the combustion process at mole fractions five to ten times higher than engine-out formaldehyde mole fractions. Formaldehyde is nearly completely destroyed during the final part of the combustion process. The test results provide insights that advance the current understanding and help direct future work on formaldehyde formation.
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Mitchell, Charles E., and Daniel B. Olsen. "Formaldehyde Formation in Large Bore Natural Gas Engines Part 1: Formation Mechanisms." Journal of Engineering for Gas Turbines and Power 122, no. 4 (December 29, 1999): 603–10. http://dx.doi.org/10.1115/1.1290585.

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Recent testing of exhaust emissions from large bore natural gas engines has indicated that formaldehyde CH2O is present in amounts that are significant relative to hazardous air pollutant standards. In consequence, a detailed literature review has been carried out at Colorado State University to assess the current state of knowledge about formaldehyde formation mechanisms and evaluate its applicability to gas engines. In this paper the following topics from that review, which bear directly on formaldehyde formation in natural gas engines, are discussed: (1) post combustion equilibrium concentrations; (2) chemical kinetics; (3) flame propagation and structure; (4) partial oxidation possibilities; and (5) potential paths for engine out formaldehyde. Relevant data taken from the literature on equilibrium concentrations and in-flame temperatures and concentrations are presented in graphical form. A map of possible paths for engine out formaldehyde is used to summarize results of the review, and conclusions relative to formation and destruction mechanisms are presented. [S0742-4795(00)00904-2]
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Olsen, Daniel B., and Charles E. Mitchell. "Formaldehyde Formation in Large Bore Engines Part 2: Factors Affecting Measured CH2O." Journal of Engineering for Gas Turbines and Power 122, no. 4 (December 29, 1999): 611–16. http://dx.doi.org/10.1115/1.1290586.

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Current research shows that the only hazardous air pollutant of significance emitted from large bore natural gas engines is formaldehyde CH2O. A literature review on formaldehyde formation is presented focusing on the interpretation of published test data and its applicability to large bore natural gas engines. The relationship of formaldehyde emissions to that of other pollutants is described. Formaldehyde is seen to have a strong correlation to total hydrocarbon (THC) level in the exhaust. It is observed that the ratio of formaldehyde to THC concentration is roughly 1.0–2.5 percent for a very wide range of large bore engines and operating conditions. The impact of engine operating parameters, load, rpm, spark timing, and equivalence ratio, on formaldehyde emissions is also evaluated. [S0742-4795(00)01004-8]
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Olsen, D. B., G. C. Hutcherson, B. D. Willson, and C. E. Mitchell. "Development of the Tracer Gas Method for Large Bore Natural Gas Engines—Part II: Measurement of Scavenging Parameters." Journal of Engineering for Gas Turbines and Power 124, no. 3 (June 19, 2002): 686–94. http://dx.doi.org/10.1115/1.1454117.

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In this work the tracer gas method using nitrous oxide as the tracer gas is implemented on a stationary two-stroke cycle, four-cylinder, fuel-injected large-bore natural gas engine. The engine is manufactured by Cooper-Bessemer, model number GMV-4TF. It is representative of the large bore natural gas stationary engine fleet currently in use by the natural gas industry for natural gas compression and power generation. Trapping efficiency measurements are carried out with the tracer gas method at various engine operating conditions, and used to evaluate the scavenging efficiency and trapped A/F ratio. Scavenging efficiency directly affects engine power and trapped A/F ratio has a dramatic impact on pollutant emissions. Engine operating conditions are altered through variations in boost pressure, speed, back pressure, and intake port restriction.
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Rossegger, Bernhard, Albrecht Leis, Martin Vareka, Michael Engelmayer, and Andreas Wimmer. "Lubricating Oil Consumption Measurement on Large Gas Engines." Lubricants 10, no. 3 (March 8, 2022): 40. http://dx.doi.org/10.3390/lubricants10030040.

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Increasing the reliability of combustion engines while further reducing emissions and life cycle costs are the main drivers for optimizing lubricating oil consumption (LOC). However, in order to reduce the lube oil consumption of an engine, it is crucial to measure it accurately. Therefore, a LOC measurement device based on the use of the stable isotope deuterium has been developed. Previous publications have focused on the use of passenger car engines. This publication describes the first application of this newly developed method on a large gas engine. This is of particular interest as large-bore engines might show different oil consumption behavior, much higher LOC in gram per hour and the bigger oil reservoir need larger amounts of tracer. Additionally, a different type of fuel has an effect on oil consumption measurement as well, as presented in this paper. The results showed this method can be applied to large gas engines as well after conducting minor changes to the measurement setup. However, other than liquid fuels, the origin and isotopic composition of the natural gas has to be monitored. Ideally, gas from large storage is used for carrying out these measurements.
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Adair, J., D. Olsen, and A. Kirkpatrick. "Exhaust Tuning of Large-Bore, Multicylinder, Two-Stroke, Natural Gas Engines." International Journal of Engine Research 7, no. 2 (April 1, 2006): 131–41. http://dx.doi.org/10.1243/146808705x58297.

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In this paper, computational modelling of the exhaust system of two types of large-bore, multicylinder, two-stroke engine is performed. The airflow performance of a four-cylinder V-bank Cooper GMV-4TF engine and a six-cylinder in-line Clark TLA engine is simulated. The simulation includes the computation of pressure wave propagation in the exhaust manifold. Using a modified method of the steepest ascent numerical technique, tuned exhaust manifolds are designed for each engine with the objective of reduced NO emissions. The NO reduction is accomplished by increasing the trapped cylinder mass and correspondingly reducing the peak combustion temperature. The simulations predict NO reductions in the range 10–30 per cent as a result of exhaust tuning.
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Kim, Gi-Heon, Allan Kirkpatrick, and Charles Mitchell. "Supersonic Virtual Valve Design for Numerical Simulation of a Large-Bore Natural Gas Engine." Journal of Engineering for Gas Turbines and Power 129, no. 4 (February 20, 2007): 1065–71. http://dx.doi.org/10.1115/1.2747251.

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In many applications of supersonic injection devices, three-dimensional computation that can model a complex supersonic jet has become critical. However, in spite of its increasing necessity, it is computationally costly to capture the details of supersonic structures in intricate three-dimensional geometries with moving boundaries. In large-bore stationary natural gas fueled engine research, one of the most promising mixing enhancement technologies currently used for natural gas engines is high-pressure fuel injection. Consequently, this creates considerable interest in three-dimensional computational simulations that can examine the entire injection and mixing process in engines using high-pressure injection and can determine the impact of injector design on engine performance. However, the cost of three-dimensional engine simulations—including a moving piston and the kinetics of combustion and pollutant production—quickly becomes considerable in terms of simulation time requirements. One limiting factor is the modeling of the small length scales of the poppet valve flow. Such length scales can be three orders of magnitude smaller than cylinder length scales. The objective of this paper is to describe the development of a methodology for the design of a simple geometry supersonic virtual valve that can be substituted in three-dimensional numerical models for the complex shrouded poppet valve injection system actually installed in the engine to be simulated. Downstream flow characteristics of the jets from an actual valve and various virtual valves are compared. Relevant mixing parameters, such as local equivalent ratio and turbulence kinetic energy, are evaluated in full-scale moving piston simulations that include the effect of the jet-piston interaction. A comparison of the results has indicated that it is possible to design a simple converging-diverging fuel nozzle that will produce the same jet and, subsequently, the same large-scale and turbulent-scale mixing patterns in the engine cylinder as a real poppet valve.
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Mashayekh, Alireza, Timothy Jacobs, Mark Patterson, and John Etcheverry. "Prediction of air–fuel ratio control of a large-bore natural gas engine using computational fluid dynamic modeling of reed valve dynamics." International Journal of Engine Research 18, no. 9 (January 6, 2017): 900–908. http://dx.doi.org/10.1177/1468087416686224.

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Air–fuel ratio control of large-bore, two-stroke, natural gas engines, typically used in the oil and gas field, is critically important to maintain stable operation and emission compliance. Many two-stroke applications rely on reed valves to control air and gas induction, which can involve complicated gas flow behavior; standard gas dynamic relationships are typically insufficient to characterize such behavior. Computational fluid dynamic simulations offer the needed complexity, but even so the computational fluid dynamic models, as shown in this work, must also capture the dynamic behavior of the valves themselves. The current work reports on a computational fluid dynamics–based model representing this type of large-bore, two-stroke, natural gas engine using commercially available computational fluid dynamic software. The engine under study is an AJAX E-565 with rated power of 30 kW (40 HP), a bore of 216 mm (8½″), and a stroke of 254 mm (10″). The large engine geometry makes a relatively large solution domain, hence requiring an intense, time-consuming numerical investigation. This large-bore engine works at a rated speed of 525 RPM with a compression ratio of 6 to 1. Two approaches to modeling the reed valve are investigated: (1) a pressure difference–based user-defined function and (2) a fluid–structure interaction user-defined function. The pressure difference–based user-defined function captures reed valve behavior in a simple, binary fashion (i.e. valves are either open or closed based on the pressure difference between the intake pipe and the engine’s stuffing box). The fluid–structure interaction user-defined function, however, predicts the motion of the reed valve strips based on fluid and body motions; although a more complex solution, the fluid–structure interaction user-defined function accurately predicts the engine’s gas exchange process. In this article, the results of each method are presented and validated to show that the added complexity is necessary to properly predict (and thus eventually improve) the engine’s air–fuel ratio control.
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Liu, Long, Shihai Liu, Qian Xia, Bo Liu, and Xiuzhen Ma. "Numerical Investigation on Mixing Characteristics and Mechanism of Natural Gas/Air in a Super-Large-Bore Dual-Fuel Marine Engine." Atmosphere 13, no. 9 (September 19, 2022): 1528. http://dx.doi.org/10.3390/atmos13091528.

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Premixed combustion mode dual-fuel (DF) engines are widely used in large-bore marine engines due to their great potential to solve the problem of CO2 emissions. However, detonation is one of the main problems in the development of marine engines based on the premixed combustion mode, which affects the popularization of liquefied natural gas (LNG) engines. Due to the large bore and long stroke, marine dual-fuel engines have unique flow characteristics and a mixture mechanism of natural gas and air. Therefore, the purpose of this study is to present a simulated investigation on the influence of swirl on multiscale mixing and the concentration field, which provides a new supplement for mass transfer theory and engineering applications. It is suggested that the phenomenon of abnormal combustion occurs on account of the distribution of the mixture being uneven in a super-large-bore dual-fuel engine. Further analysis showed that the level of swirl at the late compression stage and the turbulence intensity are the decisive factors affecting the transmission process of natural gas (NG) and distribution of methane (CH4) concentration. Finally, a strategy of improving mixture quality and the distribution of the mixture was proposed.
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Dissertations / Theses on the topic "Large bore gas engine"

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Kendrick, Clint Edward. "Development of model for large-bore engine cooling systems." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8721.

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Master of Science
Department of Mechanical and Nuclear Engineering
Kirby S. Chapman
The purpose of this thesis is to present on the development and results of the cooling system logic tree and model developed as part of the Pipeline Research Council International, Inc (PRCI) funded project at the Kansas State National Gas Machinery Laboratory. PRCI noticed that many of the legacy engines utilized in the natural gas transmission industry were plagued by cooling system problems. As such, a need existed to better understand the heat transfer mechanisms from the combusting gases to the cooling water, and then from the cooling water to the environment. To meet this need, a logic tree was developed to provide guidance on how to balance and identify problems within the cooling system and schedule appropriate maintenance. Utilizing information taken from OEM operating guides, a cooling system model was developed to supplement the logic tree in providing further guidance and understanding of cooling system operation. The cooling system model calculates the heat loads experienced within the engine cooling system, the pressures within the system, and the temperatures exiting the cooling equipment. The cooling system engineering model was developed based upon the fluid dynamics, thermodynamics, and heat transfer experienced by the coolant within the system. The inputs of the model are familiar to the operating companies and include the characteristics of the engine and coolant piping system, coolant chemistry, and engine oil system characteristics. Included in the model are the various components that collectively comprise the engine cooling system, including the water cooling pump, aftercooler, surge tank, fin-fan units, and oil cooler. The results of the Excel-based model were then compared to available field data to determine the validity of the model. The cooling system model was then used to conduct a parametric investigation of various operating conditions including part vs. full load and engine speed, turbocharger performance, and changes in ambient conditions. The results of this parametric investigation are summarized as charts and tables that are presented as part of this thesis.
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Van, Norden Vincent Ray. "Reducing emissions of a large bore two stroke cycle engine using a natural gas and hydrogen mixture." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/736.

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Grauer, Diana Kathryn. "Simulation and optimization of non-isothermal compressible flow through large-bore two-stroke cycle natural gas transmission engines." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4230.

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Coates, Tim. "Numerical simulation of unconventional aero-engine exhaust systems for aircraft." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16365.

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This thesis investigates the impact of upstream duct convolution on the plume development for high speed jets. In particular, investigations are carried out into an unconventional aero-engine exhaust systems comprised of a modified convergent-divergent rectangular nozzle where the converging section of the nozzle includes an S-bend in the duct. The motivation for this work comes from both the military and civilian sectors of the aerospace industry. The growing interest into highly efficient engines in the civilian sector and increasing complexities involved in stealth technologies for military applications has led to new design constraints on aero-engine exhaust systems that require further research into flows through more complex duct geometries. Due to a lack of experimental data into this area in the open literature validation studies are undertaken into flows through an S-bend duct and exhaust plume development from a rectangular convergent-divergent nozzle. The validation work is simulated using RANS CFD with common industrial turbulence models as well as LES with artificial inlet conditions. Subsequently, a CFD investigation into three unconventional aero-engine exhaust systems, with over-expanded conditions, with differing angles of curvature across the converging S-bend is undertaken using both RANS and LES methodologies governed by the validation work. As the curvature of the S-bend was increased it was found that the thrust and effective NPR both decrease. Whilst these changes were within acceptable levels (with some optimisation) for a circumferential extent of up to 53.1 the losses became prohibitive large at extents. For the ducts with a greater circumferential extents separation was seen to occur at the throat of the nozzle; this changes the design parameters of the nozzle leading to a higher Mach number and could potentially be harnessed to improve performance of the engine creating a `variable throat' nozzle. The impact of using different numerical solvers to simulate the flow through an unconventional aero-engine exhaust system has also been considered. The use of LES has shown that the octagonal, hexahedral and trapezoidal shapes initially observed in the development of the plumes of the RANS cases are likely to be an artifact caused by the RANS solver, as would the transverse total pressure gradients observed in the RANS cases at the nozzle exit as they are both absent from all of the LES results. Likewise the implementation of realistic inlet conditions has a significant impact on the development of the plume, particularly in the length of the potential core and the number of shock cells.
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Sakowitz, Alexander. "Computation and Analysis of EGR Mixing in Internal Combustion Engine Manifolds." Doctoral thesis, KTH, Mekanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-117911.

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This thesis deals with turbulent mixing processes occurring in internal combustion engines, when applying exhaust gas recirculation (EGR). EGR is a very efficient way to reduce emissions of nitrogen oxides (NOx) in internal combustion engines. Exhaust gases are recirculated and mixed with the fresh intake air, reducing the oxygen con- centration of the combustion gas and thus the peak combustion temperatures. This temperature decrease results in a reduction of NOx emissions. When applying EGR, one is often faced with non-uniform distribution of exhaust among and inside the cylinders, deteriorating the emission performance. The mixing of exhaust gases and air is governed by the flow in the engine intake manifold, which is characterized by unsteadiness due to turbulence and engine pulsations. Moreover, the density cannot be assumed to be constant due to the presence of large temperature variations.Different flow cases having these characteristics are computed by compressible Large Eddy Simulations (LES). First, the stationary flows in two T-junction type geometries are investigated. The method is validated by comparison with experimental data and the accuracy of the simulations is confirmed by grid sensitivity studies. The flow structures and the unsteady flow modes are described for a range of mass flow ratios between the main and the branch inlet. A comparison to RANS computations showed qualitatively different flow fields.Thereafter, pulsating inflow conditions are prescribed on the branch inlet in or- der to mimic the large pulsations occurring in the EGR loop. The flow modes are investigated using Dynamical Mode Decomposition (DMD).After having established the simulation tool, the flow in a six-cylinder engine is simulated. The flow is studied by Proper Orthogonal Decomposition (POD) and DMD. The mixing quality is studied in terms of cylinder-to-cylinder non-uniformity and temporal and spatial variances. It was found that cycle-averaging of the concentration may give misleading results. A sensitivity study with respect to changes in the boundary conditions showed that the EGR pulsations, have large influence on the results. This could also be shown by POD of the concentration field showing the significance of the pulses for the maldistribution of exhaust gases.Finally, the flow in an intake manifold of a four-cylinder engine is investigated in terms of EGR distribution. For this geometry, pipe bends upstream of the EGR inlet were found to be responsible for the maldistribution.

QC 20130207

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Gao, Hongxun. "Investigation of a railplug ignition system for lean-burn large-bore natural gas engines." Thesis, 2005. http://hdl.handle.net/2152/2425.

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Books on the topic "Large bore gas engine"

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American Society of Mechanical Engineers. Diesel and Gas Engine Power Division. Technical Conference. New developments in large bore engines: Presented at the Diesel and Gas Engine Power Division, Technical Conference, West Middlesex, Pennsylvania, October 6-8, 1985. New York, N.Y. (345 E. 47th St., New York 10017): American Society of Mechanical Engineers, 1985.

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Castaldini, Carlo. Environmental assessment of NOx control on a compression-ignition, large-bore, reciprocating internal-combustion engine. Research Triangle Park, NC: U.S. Environmental Protection Agency, Air and Energy Engineering Research Laboratory, 1986.

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Castaldini, Carlo. Environmental assessment of NOx control on a spark-ignited, large-bore, reciprocating internal-combustion engine. Research Triangle Park, NC: U.S. Environmental Protection Agency, Air and Energy Engineering Research Laboratory, 1986.

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B, Chrisman, and American Society of Mechanical Engineers. Internal Combustion Engine Division., eds. New technology in large bore engines: Presented at the 12th Annual Fall Technical Conference of the ASME Internal Combustion Engine Division, October 7-10, 1990. New York, N.Y: American Society of Mechanical Engineers, 1990.

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ASME. Print Proceedings of the ASME 2017 Internal Combustion Engine Fall Technical Conference : Volume 1: Large Bore Engines; Fuels; Advanced Combustion. American Society of Mechanical Engineers, The, 2017.

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American Society of Mechanical Engineers. Print Proceedings of the ASME 2018 Internal Combustion Engine Fall Technical Conference : Volume 1: Large Bore Engines; Fuels; Advanced Combustion. American Society of Mechanical Engineers, The, 2019.

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ASME. Print Proceedings of the ASME 2015 Internal Combustion Engine Division Fall Technical Conference : Volume 1: Large Bore Engines; Fuels; Advanced Combustion. American Society of Mechanical Engineers, The, 2016.

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Book chapters on the topic "Large bore gas engine"

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Zelenka, Jan, Claudio Hoff, Martin Kirsten, and Andreas Wimmer. "Approaches to Meeting Fluctuating Natural Gas Quality in Large Bore Engine Applications." In Knocking in Gasoline Engines, 17–33. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-69760-4_2.

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Schlick, Harald, Shinsuke Murakami, Thomas Kammerdiener, Maria Segura Carrasco, and Günter Figer. "Hydrogen Large Bore Engine Technology – More than a Bridging Technology." In Heavy-Duty-, On- und Off-Highway-Motoren 2021, 86–99. Wiesbaden: Springer Fachmedien Wiesbaden, 2022. http://dx.doi.org/10.1007/978-3-658-38105-9_7.

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Bechir, Sabri. "Optimization of the Combustion in Large Marine Diesel Engine by Controlling the Exhaust Gas." In Lecture Notes in Mechanical Engineering, 3–10. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37143-1_1.

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Antunes, J., R. Mikalsen, and A. Roskilly. "Conversion of large-bore diesel engines for heavy fuel oil and natural gas dual fuel operation." In Maritime Engineering and Technology, 121–26. CRC Press, 2012. http://dx.doi.org/10.1201/b12726-19.

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"Conversion of large-bore diesel engines for heavy fuel oil and natural gas dual fuel operation." In Maritime Engineering and Technology, 135–40. CRC Press, 2012. http://dx.doi.org/10.1201/b12726-21.

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Ganesan, Timothy, Pandian Vasant, Igor Litvinchev, and Mohd Shiraz Aris. "Extreme Value Metaheuristics and Coupled Mapped Lattice Approaches for Gas Turbine-Absorption Chiller Optimization." In Advances in Computer and Electrical Engineering, 283–312. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-3970-5.ch014.

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The increasing complexity of engineering systems has spurred the development of highly efficient optimization techniques. This chapter focuses on two novel optimization methodologies: extreme value stochastic engines (random number generators) and the coupled map lattice (CML). This chapter proposes the incorporation of extreme value distributions into stochastic engines of conventional metaheuristics and the implementation of CMLs to improve the overall optimization. The central idea is to propose approaches for dealing with highly complex, large-scale multi-objective (MO) problems. In this work the differential evolution (DE) approach was employed (incorporated with the extreme value stochastic engine) while the CML was employed independently (as an analogue to evolutionary algorithms). The techniques were then applied to optimize a real-world MO Gas Turbine-Absorption Chiller system. Comparative analyses among the conventional DE approach (Gauss-DE), extreme value DE strategies, and the CML were carried out.
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Scamardella, Filippo, Giorgio Zamboni, Edward Canepa, Paola Gualeni, and Angelo Macocco. "Ammonia as an Alternative Fuel for Large Passenger Ships: Benefits and Challenges." In Progress in Marine Science and Technology. IOS Press, 2022. http://dx.doi.org/10.3233/pmst220018.

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The shipping industry is under increasing pressure to comply with new demanding requirements for exhaust gas emissions. Alternative fuels as well as new technologies need to be developed to meet these goals and reduce Green-House Gases (GHG). This paper investigates ammonia as an alternative fuel for the cruise ship market. A focus is given on the regulatory framework (e.g. EU, IMO and Classification Societies) that at present defines requirements for gaseous emissions and design principles of the fuel containment as well as supply systems. Ammonia allows for effective reduction of CO2 but is potentially toxic for human life and the environment. Due to the innovative nature of ammonia as a fuel, the regulatory approach is based mainly on alternative design instead of prescriptive rules. A case – study, with Internal Combustion Engine ICE (Dual-Fuel) and Propulsion Electric Motors (PEM) as selected standard propulsion system, has been carried out to investigate the impacts of ammonia as fuel on a large passenger ship. The purpose is to evaluate the variation of navigation autonomy, arrangement and weights/stability, considering also specific storage and handling requirements.
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Mocerino, Luigia, Vincenzo Piscopo, and Antonio Scamardella. "Sensitivity Analysis of a Marine Gasoline Engine: From Power to Emissions." In Progress in Marine Science and Technology. IOS Press, 2022. http://dx.doi.org/10.3233/pmst220026.

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Numerical simulations currently represent a valid aid to assess the performance of marine engines. Anyway, most of past applications generally focused on large supercharged 4-stroke diesel engines, while few results are available in the literature for fast outboard engines, generally installed onboard recreational crafts. Therefore, a case study on a fast outboard diesel engine (4T, 6300 rpm, 350 hp) is currently provided and discussed. The simulations are performed in the Ricardo Wave environment, where NOX and CO emissions are estimated, in addition to the typical engine performances. The data, required for the model calibration, were obtained from the engine manufacturer datasheets, as well as from a set of available sea trials. Nevertheless, not all parameters were available, so as some of them were selected based on past experience or in accordance with similarly sized diesel engines, after performing a preliminary sensitivity analysis. As concerns the assessment of NOX and CO emissions, different simulation methods are embodied to assess the chemical equilibrium in the combustion chamber and investigate the relevant incidence in terms of time effort amount, and estimated results. Current simulations reveal to be also useful to model dual fuel (gasoline/natural gas) engines and evaluate the impact of this type of alternative plant on consumption and air emissions.
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Lippert, A., C. Trapp, J. Laubach, C. Nelson, F. Nota, A. Avagliano, and N. Prendiville. "GE’s J920 Großgasmotor kombiniert wegweisende Technologien und innovatives Digital Monitoring, um mehr als 50 % elektrischen Wirkungsgrad zu erreichen /GE’s J920 Large Gas Engine Incorporates Latest T..." In 38. Internationales Wiener Motorensymposium 27.-28. April 2017, I—285—II—X. VDI Verlag, 2017. http://dx.doi.org/10.51202/9783186802125-i-285.

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Crane, Hewitt, Edwin Kinderman, and Ripudaman Malhotra. "Our Energy Inheritance: Fossil Fuels." In A Cubic Mile of Oil. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195325546.003.0014.

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The use of fossil fuels—petroleum, natural gas, and coal—is ubiquitous today and has made possible the advances of modern civilization. These fuels are capable of providing energy for a variety of applications—from very small to very large—and touch our lives in many ways. A small gas-fired heater uses about 50,000 Btu/hr (1 standard cubic foot [scf] of gas/min) and keeps our homes warm. A 200-horsepower gasoline engine in a family car consumes around 2 gal/hr of oil and can carry a load of five passengers a distance of 60 miles on a level highway. An 1,800-ton/hr cement plant consumes 900 MBtu/hr (about 0.9 million scf gas/hr) when in full operation and produces the building material widely used for constructing homes, offices, industries, roads, and bridges. A large, coal-fired electric power station (1,000 MW rating) requires between 300 and 500 tons of coal per hour and produces enough electricity to power half a million homes. The range of power that fossil fuels, particularly oil, can deliver is truly amazing: the same basic fuel that powers jet aircraft also powers children’s model aircraft engines. It is unlikely that aircraft will ever be powered by solar panels mounted on the wings or by on-board nuclear reactors. The importance of fossil fuels in our lives cannot be overemphasized. It took millions of years to accumulate them, and their potential exhaustion in just a few centuries should seriously concern all of us. In this chapter, we briefly review the circumstances that led to formation of our fossil fuels and then discuss how much of each of them is available. This discussion requires clarifying the special meanings ascribed to such terms as reserves and resources. For all three fuels, we look at the global distribution of our resources. We also present estimates of possible resource lifetimes under varying conditions of use and indicate the nominal equipment and infrastructure requirements for producing these inherited resources at a rate of 1 CMO/yr. As we shall see, our conventional reserves are somewhat limited, but our resource base is large, and unconventional oil and gas resources offer a substantially greater potential. Nonetheless, exploiting unconventional resources is certain to be more expensive and, in most cases, potentially more damaging to the environment.
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Conference papers on the topic "Large bore gas engine"

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Gao, Hongxun, Matt J. Hall, Ofodike A. Ezekoye, and Ron D. Matthews. "Railplug Design Optimization to Improve Large-Bore Natural Gas Engine Performance." In ASME 2005 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ices2005-1031.

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It is a very challenging problem to reliably ignite extremely lean mixtures, especially for the low speed, high load conditions of stationary large-bore natural gas engines. If these engines are to be used for the distributed power generation market, it will require operation with higher boost pressures and even leaner mixtures. Both place greater demands on the ignition system. The railplug is a very promising ignition system for lean burn natural gas engines with its high-energy deposition and high velocity plasma jet. High-speed photography was used to study the discharge process. A heat transfer model is proposed to aid the railplug design. A parameter study was performed both in a constant volume bomb and in an operating natural gas engine to improve and optimize the railplug designs. The engine test results show that the newly designed railplugs can ensure the ignition of very lean natural gas mixtures and extend the lean stability limit significantly. The new railplug designs also improve durability.
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Ruter, Matthew D., Daniel B. Olsen, Mark V. Scotto, and Mark A. Perna. "Performance of a Large Bore Natural Gas Engine With Reformed Natural Gas Prechamber Fueling." In ASME 2010 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/icef2010-35162.

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Lean combustion is a standard approach used to reduce NOx emissions in large bore natural gas engines. However, at lean operating points, combustion instabilities and misfires give rise to high total hydrocarbon (THC) and carbon monoxide (CO) emissions. To counteract this effect, precombustion chamber (PCC) technology is employed to allow engine operation at an overall lean equivalence ratio while mitigating the rise of THC and CO caused by combustion instability and misfires. A PCC is a small chamber, typically 1–2% of the clearance volume. A separate fuel line supplies gaseous fuel to the PCC and a standard spark plug ignites the slightly rich mixture (equivalence ratio 1.1 to 1.2) in the PCC. The ignited PCC mixture enters the main combustion chamber as a high energy flame jet, igniting the lean mixture in the main chamber. Typically, natural gas fuels both the main cylinder and the PCC. In the current research, a mixture of reformed natural gas (syngas) and natural gas fuels the PCC. Syngas is a broad term that refers to a synthetic gaseous fuel. In this case, syngas specifically denotes a mixture of hydrogen, carbon monoxide, nitrogen, and methane generated in a natural gas reformer. Syngas has a faster flame speed and a wider equivalence ratio range of operation. Fueling the PCC with Syngas reduces combustion instabilities and misfires. This extends the overall engine lean limit, enabling further NOx reductions. Research results presented are aimed at quantifying the benefits of syngas PCC fueling. A model is developed to predict equivalence ratio in the PCC for different mixtures and flowrates of fuel. An electronic injection valve is used to supply the PCC with syngas. The delivery pressure, injection timing, and flow rate are varied to optimize PCC equivalence ratio. The experimental results show that supplying the PCC with syngas improves combustion stability by 16% compared to natural gas PCC fueling. Comparing equivalent combustion stability operating points between syngas mixtures and natural gas shows a 40% reduction in NOx emissions when fueling the PCC with syngas mixtures compared to natural gas fueling.
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Kim, Gi-Heon, Allan Kirkpatrick, and Charles Mitchell. "Computational Modeling of Natural Gas Injection in a Large Bore Engine." In ASME 2002 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/icef2002-501.

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The topic of this paper is the computational modeling and experimental visualization of gas injection in a large bore engine. The injection process is accomplished through the use of a mechanically or electrically controlled poppet valve. The objective of the paper is to more fully understand the significance of the poppet valve and the piston top in controlling the mixing of the injected fuel with the air in the cylinder. In this paper, the flow past the poppet valve into the engine cylinder is computed using computational fluid dynamics (CFD) for both a low (4 bar) and a high pressure (34 bar) injection process using unshrouded and shrouded valves. Flow visualization using planar laser induced fluorescence (PLIF) is used to visualize the actual fluid flow. The results indicate that for low pressures the gas flow around the poppet valve collapses downstream of the poppet. At high pressure, the gas flow does not collapse, but flows along the cylinder wall, producing poor mixing in the cylinder. To obtain satisfactory fluid flow at high pressure, the results indicated a shroud should be employed around the poppet valve to direct the gas into the center of the cylinder. Additional computations show that at top dead center, the flammable mixture and fuel mass fraction for the high-pressure injection are significantly greater than for the low-pressure injection.
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Kammerstätter, S., S. Bauer, and T. Sattelmayer. "Jet-Penetration in Prechamber-Ignited Lean Large-Bore Natural Gas Engines." In ASME 2012 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icef2012-92031.

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Combustion in lean large-bore natural gas engines is usually initiated by gas-scavenged prechambers. The hot reacting products of the combustion in the prechamber penetrate the main chamber as reacting jets, providing high ignition energy for the lean main chamber charge. The shape and intensity of the reaction zone in these jets are the key elements for efficient ignition and heat release in the main chamber. The influence of geometrical and operational parameters on the reaction during jet penetration was investigated in detail. As the periodically chargeable high pressure combustion cell used in the study provides full optical access to the entire main chamber the evolution of the spatial distribution of the reaction zones was investigated in terms of OH*-chemiluminescence. As jet penetration is a very fast and highly transient process the emission of OH* was recorded at a frequency of f = 30000 Hz. The macroscopic reaction zone parameters in the jet region (penetration length and angle, reacting area and light emission) reveal the influence of orifice size and prechamber gas injection on the heat release in the shear layer between the jet and the lean charge in the main chamber. In addition, the influence of the development of the reaction in these zones on the ignition probability and the main chamber pressure rise is shown. With an appropriate selection of the combination of the prechamber orifice geometry and the operating parameters significant improvements of ignition probability and heat release in the main chamber were obtained.
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Zelenka, Jan, Claudio Hoff, Andreas Wimmer, Roland Berger, and Josef Thalhauser. "Variable Intake Valve Train to Optimize the Performance of a Large Bore Gas Engine." In ASME 2016 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icef2016-9358.

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The present paper describes the investigations made using the electro-hydraulic intake valve timing system VCM® on a large bore gas engine. The first section explains what challenges have to be faced when developing concepts for present and future applications of large bore gas engines. Following an introduction to the VCM® system, an outline is presented of expected opportunities for using variable intake valve timing in combination with modern turbocharging concepts. The second section describes 0D/1D engine cycle simulations that were carried out to assess the influence of variable valve timing on the intake side compared to a fixed intake valve profile, which is the current standard for large bore gas engines. As a result, first predictions can be made about the gain in engine efficiency achieved with different operating strategies. In order to assess the performance potentials of the variable valve train, extensive experimental investigations were carried out on a single cylinder research engine based on GE’s Type 6 gas engine. The investigations consisted of varying engine parameters including varying the geometric compression ratio as well as the engine boundary conditions. It will be shown how intake valve timing can be used to optimize engine efficiency by improving gas exchange. Furthermore, variable intake valve timing affects the overall system behavior, e.g. distances to the engine’s operating limits. Special attention was paid to analyzing combustion itself, which is necessary due to the strong influence that intake valve timing has on the thermodynamic states of the cylinder charge.
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Fercher, Bernhard, Andreas Wimmer, Jan Zelenka, Gernot Kammel, and Zita Baumann. "Assessment of Hydrogen and Natural Gas Mixtures in a Large Bore Gas Engine for Power Generation." In ASME 2020 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/icef2020-2949.

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Abstract Now more than ever there is a growing global interest to reduce greenhouse gas (GHG) emissions originating from internal combustion engines. One approach consists in the use of hydrogen instead of fossil fuels. Large bore gas engines for power generation are often fueled by gases with high methane content. Relative to natural gas-fueled engines, the power densities of premixed or port-fuel-injected hydrogen engines are limited due to low volumetric efficiencies and moreover by occurring irregular combustion events (knocking, backfire). The paper presents results from experimental investigations of the impact of different hydrogen substitution rates in natural gas on performance, emissions and operating limits on a single cylinder research engine. The engine is representative for a large bore gas engine for power generation and operates using an open chamber combustion concept with lean mixtures. Essentially, THC, CO2 and CO emissions decrease with rising hydrogen content of the fuel gas. Even with low concentrations of hydrogen in the fuel gas, significant reductions in THC emissions could be demonstrated. Usually NOX emissions will rise with unchanged operating parameters. However, if excess-air ratio and spark timing are adjusted, a net reduction of NOX emissions can be achieved while the impact on brake thermal efficiency is small. Furthermore, the paper outlines potential mitigation strategies to expand the operational limits with respect to power density with high hydrogen substitution rates.
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Chowdhury, Snehaunshu, Razi Nalim, and Thomas M. Sine. "Computational Study of Fuel Injection in a Large-Bore Gas Engine." In ASME 2003 Internal Combustion Engine and Rail Transportation Divisions Fall Technical Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/icef2003-0755.

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Emission controls in stationary gas engines have required significant modifications to the fuel injection and combustion processes. One approach has been the use of high-pressure fuel injection to improve fuel-air mixing. The objective of this study is to simulate numerically the injection of gaseous fuel at high pressure in a large-bore two-stroke engine. Existing combustion chamber geometry is modeled together with proposed valve geometry. The StarCD® fluid dynamics code is used for the simulations, using appropriate turbulence models. High-pressure injection of up to 500 psig methane into cylinder air initially at 25 psig is simulated with the valve opened instantaneously and piston position frozen at the 60 degrees ABDC position. Fuel flow rate across the valve throat varies with the instantaneous pressure but attains a steady state in approximately 22 ms. As expected with the throat shape and pressures, the flow becomes supersonic past the choked valve gap, but returns to a subsonic state upon deflection by a shroud that successfully directs the flow more centrally. This indicates the need for careful shroud design to direct the flow without significant deceleration. Pressures below 300 psig were not effective with the proposed valve geometry. A persistent re-circulation zone is observed immediately below the valve, where it does not help promote mixing.
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Olsen, Daniel B., Ryan K. Palmer, and Charles E. Mitchell. "Modeling of Formaldehyde Formation From Crevices in a Large Bore Natural Gas Engine." In ASME/IEEE 2007 Joint Rail Conference and Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/jrc/ice2007-40130.

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Formaldehyde emissions from stationary natural gas engines are regulated in the United States, as mandated by the 1990 Clean Air Act Amendments. This work aims to advance the understanding of formaldehyde formation in large bore (>36 cm) natural gas engines. Formaldehyde formation in a large bore natural gas engine is modeled utilizing computational fluid dynamics and chemical kinetics. The top land crevice volume is believed to play an important role in the formation mechanisms of engine-out formaldehyde. This work focuses specifically on the top land crevice volume in the Cooper-Bessemer LSVB large bore 4-stroke cycle natural gas engine. Chemical kinetic modeling predicts that the top land crevice volume is responsible for the formation of 22 ppm of engine-out formaldehyde. Based on a raw exhaust concentration of 80 ppm, this constitutes about 27% of engine-out formaldehyde. Simplifying assumptions made for the chemical kinetic modeling are validated using computational fluid dynamics. Computational fluid dynamic analysis provided confirmation of crevice volume mass discharge timing. It also provided detailed pressure, temperature and velocity profiles within the top land crevice volume at various crank angle degrees.
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Kim, Gi-Heon, Allan Kirkpatrick, and Charles Mitchell. "Improvement of Poppet Valve Injection Performance in Large-Bore Natural Gas Engines." In ASME 2004 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/icef2004-0845.

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Poppet valves have been used as fuel delivery mechanisms in internal combustion engines due to their excellent sealing characteristics. For example, in large-bore stationary natural gas engines, gas is directly injected by a poppet valve into the engine cylinder. The objectives of this paper are to show that a significant amount of stagnation pressure is lost during the gas flow through a conventional poppet valve and to suggest design improvements to obtain more efficient poppet valves with reduced stagnation pressure loss. In this paper, simple converging-diverging nozzles are incorporated into the poppet valve configuration to reduce the stagnation pressure loss originating from compressible flow structures. Numerical simulations of the gas flow through various poppet valve geometries were performed. Both push and pull poppet valve geometries with nozzle were studied. The stagnation pressure losses, momentum delivery downstream and downstream flow characteristics of the jets from conventional poppet valves and the modified valves were compared. A pressure-based valve injection efficiency was defined and used to compare the valve injection performance. A mixing fraction parameter was also defined to compare valve performance in a moving piston simulation. The results indicate that a conventional poppet valve is an inefficient mechanism to deliver momentum to the fuel-air mixture. Comparison of the results indicates that it is possible to make significant improvements of injection performance in momentum delivery by incorporating well-designed nozzles into the poppet valve geometry.
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Pundle, Anamol, David G. Nicol, Philip C. Malte, and Joel D. Hiltner. "Modeling the Formation of Pollutant Emissions in Large-Bore, Lean-Burn Gas Engines." In ASME 2017 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icef2017-3577.

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This paper discusses chemical kinetic modeling used to analyze the formation of pollutant emissions in large-bore, lean-burn gas reciprocating engines. Pollutants considered are NOx, CO, HCHO, and UHC. A quasi-dimensional model, built as a chemical reactor network (CRN), is described. In this model, the flame front is treated as a perfectly stirred reactor (PSR) followed by a plug flow reactor (PFR), and reaction in the burnt gas is modeled assuming a batch reactor of constant-pressure and fixed-mass for each crank angle increment. The model treats full chemical kinetics. Engine heat loss is treated by incorporating the Woschni model into the CRN. The mass burn rate is selected so that the modeled cylinder pressure matches the experiment pressure trace. Originally, the model was developed for large, low speed, two-stoke, lean-burn engines. However, recently, the model has been formatted for the four-stroke, open-chamber, lean-burn engine. The focus of this paper is the application of the model to a four-stroke engine. This is a single-cylinder non-production variant of a heavy duty lean-burn engine of about 5 liters cylinder displacement Engine speed is 1500 RPM. Key findings of this work are the following. 1) Modeled NOx and CO are found to agree closely with emission measurements for this engine over a range of relative air-fuel ratios tested. 2) This modeling shows the importance of including N2O chemistry in the NOx calculation. For λ = 1.7, the model indicates that about 30% of the NOx emitted is formed by the N2O mechanism, with the balance from the Zeldovich mechanism. 3) The modeling shows that the CO and HCHO emissions arise from partial oxidation late in the expansion stroke as unburned charge remaining mixes into the burnt gas. 4) Model generated plots of HCHO versus CH4 emission for the four-stroke engine are in agreement with field data for large-bore, lean-burn, gas reciprocating engines. Also, recent engine tests show the correlation of UHC and CO emissions to crevice volume. These tests suggest that HCHO emissions also are affected by crevice flows through partial oxidation of UHC late in the expansion stroke.
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Reports on the topic "Large bore gas engine"

1

Parks, JE. NOx Reduction with Natural Gas for Lean Large-Bore Engine Applications Using Lean NOx Trap Aftertreatment. Office of Scientific and Technical Information (OSTI), February 2005. http://dx.doi.org/10.2172/885980.

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