Download or read book Characterization of Water Injection and Urea SCR Systems for NOx Reduction in Diesel Engines written by Eric R. Snyder and published by . This book was released on 2005 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Diesel engines offer significant advantages over spark-ignited engines in terms of peak torque production, carbon monoxide (CO) emissions, hydrocarbon (HC) emissions, and fuel consumption (and associated carbon dioxide (CO2) emissions known to cause the greenhouse effect). However, lean exhaust conditions render conventional three-way catalysts ineffective, making nitrogen oxide (NOx) reduction a considerable challenge. With increasing environmental concerns and stringent pending regulation of diesel exhaust emissions, urea-Selective Catalytic Reduction (urea-SCR) has emerged as a potential technology pathway to meet US 2007/2010 and Euro IV/V NOx emissions criterion. This technology uses ammonia (NH3) generated from aqueous urea as the NOx reducing agent. Water injection in the intake system has also demonstrated the potential for significant reductions in engine-out NOx emissions.
Download or read book Urea SCR Technology for deNOx After Treatment of Diesel Exhausts written by Isabella Nova and published by Springer Science & Business Media. This book was released on 2014-03-14 with total page 715 pages. Available in PDF, EPUB and Kindle. Book excerpt: Urea-SCR Technology for deNOx After Treatment of Diesel Exhausts presents a complete overview of the selective catalytic reduction of NOx by ammonia/urea. The book starts with an illustration of the technology in the framework of the current context (legislation, market, system configurations), covers the fundamental aspects of the SCR process (catalysts, chemistry, mechanism, kinetics) and analyzes its application to useful topics such as modeling of full scale monolith catalysts, control aspects, ammonia injections systems and integration with other devices for combined removal of pollutants.
Download or read book Control of Diesel Engine Urea Selective Catalytic Reduction Systems written by Ming-Feng Hsieh and published by . This book was released on 2010 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A systematic nonlinear control methodology for urea-SCR systems applicable for light-to-heavy-duty Diesel engine platforms in a variety of on-road, off-road, and marine applications is developed and experimentally validated in this dissertation. Urea selective catalytic reduction (urea-SCR) systems have been proved of being able to reduce more than 90% of Diesel engine-out NOx emissions and have been favored by the automotive industry in recent years. Urea-SCR systems utilize ammonia, converted from 32.5% aqueous urea solution (AdBlue) injected at upstream of the SCR catalyst, as the reductant for NOx reductions. Because ammonia is considered a hazardous material, urea injection should be systematically controlled to avoid undesired tailpipe ammonia slip while achieving a sufficient level of SCR NOx reduction. The novelty of the control methodology is to regulate the ammonia storage distribution along the axial direction of a SCR catalyst to a staircase profile and thus to simultaneously realize high NOx reduction efficiency and low ammonia emissions. To achieve this control objective, several relevant subjects are studied, including: 1) aftertreatment system control-oriented modeling, 2) online NOx sensor ammonia cross-sensitivity correction, 3) SCR catalyst ammonia coverage ratio estimation, as well as 4) adaptive urea dosing controller design. A unique SCR system which consists of a urea injector and two SCR catalysts connected in-series with several NOx and NH3 sensors is used for the study of the proposed urea-SCR control methodology. Such a SCR system is integrated with a state-of-the-art Diesel engine and aftertreatment system (DOC-DPF). The US06 test cycle experimental results show the proposed control methodology, in comparison to a conventional control strategy, is capable of improving the SCR NOx reduction by 63% and reducing the tailpipe ammonia slip amount by 74%. The contributions of this research to the art include: 1) A novel, efficient, and generalizable urea-SCR dosing control methodology; 2) Diesel engine-DOC-DPF NO/NO2 ratio control-oriented models and observer-based estimations; 3) SCR catalyst ammonia coverage ratio estimation methods; 4) An online correction approach for NOx sensor ammonia cross-sensitivity elimination; and 5) An improved SCR control-oriented model.
Download or read book Spray Wall Interaction Modelling by Dimensionless Data Analysis written by Dominik Kuhnke and published by . This book was released on 2004 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SAE 2007 08 0107 A Study on the NOx Reduction of Urea Selective Catalytic Reduction SCR System in a Heavy Duty Diesel Engine written by Hoin Kang and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A NOx emission is one of the problems of diesel engines. SCR is well known to be effective for the reduction of NOx emission. Among many types of SCR, Urea-SCR is known as the most stable. Therefore, this research focuses to evaluate a performance of urea-SCR system in a heavy-duty diesel engine. At first, urea injection system is developed and optimum injection condition is observed. Numerical model of above condition applies to simulation calculation using FLUENT, CFD code. The simulation results determine experimental method on the engine test. Therefore, the aqueous urea solution is injected to reversing direction of exhaust gas into elbow exhaust pipe. Optimal quantity of a reducing agent is estimated by using accurate programming technique under different engine loads and speeds. Furthermore, emission variation between with SCR and without SCR is compared and performance of urea-SCR system is evaluated. This research may provide the fundamental data for the practical use of urea-SCR in future.
Download or read book NOx Emission Control Technologies in Stationary and Automotive Internal Combustion Engines written by B. Ashok and published by Elsevier. This book was released on 2021-11-09 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: NOx Emission Control Technologies in Stationary and Automotive Internal Combustion Engines: Approaches Toward NOx Free Automobiles presents the fundamental theory of emission formation, particularly the oxides of nitrogen (NOx) and its chemical reactions and control techniques. The book provides a simplified framework for technical literature on NOx reduction strategies in IC engines, highlighting thermodynamics, combustion science, automotive emissions and environmental pollution control. Sections cover the toxicity and roots of emissions for both SI and CI engines and the formation of various emissions such as CO, SO2, HC, NOx, soot, and PM from internal combustion engines, along with various methods of NOx formation. Topics cover the combustion process, engine design parameters, and the application of exhaust gas recirculation for NOx reduction, making this book ideal for researchers and students in automotive, mechanical, mechatronics and chemical engineering students working in the field of emission control techniques. Covers advanced and recent technologies and emerging new trends in NOx reduction for emission control Highlights the effects of exhaust gas recirculation (EGR) on engine performance parameters Discusses emission norms such as EURO VI and Bharat stage VI in reducing global air pollution due to engine emissions
Download or read book Nitrogen oxides NOx why and how they are controlled written by and published by DIANE Publishing. This book was released on 1999 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Catalytic Reduction of NOx written by Oliver Kröcher and published by MDPI. This book was released on 2018-12-14 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Selective Catalytic Reduction of NOx" that was published in Catalysts
Download or read book Diesel Emissions and Their Control 2nd Edition written by W. Addy Majewski and published by SAE International. This book was released on 2023-12-20 with total page 1135 pages. Available in PDF, EPUB and Kindle. Book excerpt: Engineers, applied scientists, students, and individuals working to reduceemissions and advance diesel engine technology will find the secondedition of Diesel Emissions and Their Control to be an indispensablereference. Whether readers are at the outset of their learning journey orseeking to deepen their expertise, this comprehensive reference bookcaters to a wide audience.In this substantial update to the 2006 classic, the authors have expandedthe coverage of the latest emission technologies. With the industryevolving rapidly, the book ensures that readers are well-informed aboutthe most recent advances in commercial diesel engines, providing acompetitive edge in their respective fields. The second edition has alsostreamlined the content to focus on the most promising technologies.This book is rooted in the wealth of information available on DieselNet.com, where the “Technology Guide” papers offer in-depth insights. Eachchapter includes links to relevant online materials, granting readers accessto even more expertise and knowledge.The second edition is organized into six parts, providing a structuredjourney through every aspect of diesel engines and emissions control: Part I: A foundational exploration of the diesel engine, combustion, andessential subsystems. Part II: An in-depth look at emission characterization, health andenvironmental impacts, testing methods, and global regulations. Part III: A comprehensive overview of diesel fuels, covering petroleumdiesel, alternative fuels, and engine lubricants. Part IV: An exploration of engine efficiency and emission controltechnologies, from exhaust gas recirculation to engine control. Part V: The latest developments in diesel exhaust aftertreatment,encompassing catalyst technologies and particulate filters. Part VI: A historical journey through the evolution of dieselengine technology, with a focus on heavy-duty engines in the NorthAmerican market. (ISBN 9781468605693, ISBN 9781468605709, ISBN 9781468605716, DOI: 10.4271/9781468605709)
Download or read book Urea SCR Technology for deNOx After Treatment of Diesel Exhausts written by Isabella Nova and published by Springer. This book was released on 2016-09-03 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Urea-SCR Technology for deNOx After Treatment of Diesel Exhausts presents a complete overview of the selective catalytic reduction of NOx by ammonia/urea. The book starts with an illustration of the technology in the framework of the current context (legislation, market, system configurations), covers the fundamental aspects of the SCR process (catalysts, chemistry, mechanism, kinetics) and analyzes its application to useful topics such as modeling of full scale monolith catalysts, control aspects, ammonia injections systems and integration with other devices for combined removal of pollutants.
Download or read book Advanced Direct Injection Combustion Engine Technologies and Development written by H Zhao and published by Elsevier. This book was released on 2014-01-23 with total page 325 pages. Available in PDF, EPUB and Kindle. Book excerpt: Direct injection enables precise control of the fuel/air mixture so that engines can be tuned for improved power and fuel economy, but ongoing research challenges remain in improving the technology for commercial applications. As fuel prices escalate DI engines are expected to gain in popularity for automotive applications. This important book, in two volumes, reviews the science and technology of different types of DI combustion engines and their fuels. Volume 1 deals with direct injection gasoline and CNG engines, including history and essential principles, approaches to improved fuel economy, design, optimisation, optical techniques and their applications. Reviews key technologies for enhancing direct injection (DI) gasoline engines Examines approaches to improved fuel economy and lower emissions Discusses DI compressed natural gas (CNG) engines and biofuels
Download or read book Urban Air Quality in Europe written by Mar Viana and published by Springer. This book was released on 2014-06-13 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an overview of air quality in urban environments in Europe, focusing on air pollutant emission sources and formation mechanisms, measurement and modeling strategies, and future perspectives. The emission sources described are biomass burning, vehicular traffic, industry and agriculture, but also African dust and long-range transport of pollutants across the European regions. The impact of these emission sources and processes on atmospheric particulate matter, ozone, nitrogen oxides and volatile and semi-volatile organic compounds is discussed and critical areas for particulate matter and nitrogen dioxide in Europe are identified. Finally, this volume presents future perspectives, mainly regarding upcoming air quality monitoring strategies, metrics of interest, such as submicron and nanoparticles, and indoor and outdoor exposure scenarios.
Download or read book Design and Development of Heavy Duty Diesel Engines written by P. A. Lakshminarayanan and published by Springer Nature. This book was released on 2019-11-05 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended to serve as a comprehensive reference on the design and development of diesel engines. It talks about combustion and gas exchange processes with important references to emissions and fuel consumption and descriptions of the design of various parts of an engine, its coolants and lubricants, and emission control and optimization techniques. Some of the topics covered are turbocharging and supercharging, noise and vibrational control, emission and combustion control, and the future of heavy duty diesel engines. This volume will be of interest to researchers and professionals working in this area.
Download or read book Study on Mixing Modelling and Control of an SCR System written by Xinna Tian and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, more and more research attention has been paid to the NOx emissions caused by marine diesel engines. Selective catalytic reduction (SCR) system has been proven to be an effective technology for the removal of NOx emitted from marine diesel engines. In order to comply with stringent International Maritime Organization (IMO) Tier III NOx emission regulations, a number of engine manufacturers have developed their own SCR systems with an option of installing SCR reactors before or after the turbines of engine turbochargers. This thesis focuses on modelling of evaporation and decomposition of urea-water-solution (UWS) droplets, design and optimisation of static mixers, modelling of an SCR reactor and developing model-based urea dosing control strategy.The amount of ammonia converted from UWS has a significant effect on the NOx removal efficiency of SCR systems. Due to a limited installation space for SCR systems on board, choosing the location of urea injection nozzle appropriately has become a critical issue for SCR system design. An evaporation and decomposition model of UWS droplets has been developed in this research in order to determine the total depletion time of a UWS droplet, which is helpful to calculate the proper length between the urea nozzle and reactor of an SCR system.In order to achieve a high NOx removal rate and reduce the quantity of NH3 slip, static mixers are commonly used before SCR reactors to improve the mixing between ammonia and exhaust gases. 4 novel static mixers have been designed and the performance of the mixers is compared in the study. An experiment has been conducted to validate the mixing performance and pressure loss of the static mixers developed. It shows that there is a satisfied agreement between the simulation and experiment results.A mathematical model of SCR reactors has been established. The unknown parameters of the model are identified by minimising the error between the model predicted and measured values of both the temperature and the species concentration after the SCR reactor. The SCR reactor model is further used in a simulation for the purpose of developing model-based urea dosing control strategies.A state observer is used to determine the actual states in the reactor which supplies the mandatory information for developing model-based urea dosing control strategies. The NH3 cross-sensitivity of NOx sensors can be described by a linear equation. The simulation results of the observer show that the NH3 cross-sensitivity of NOx sensors can be neglected when estimating the actual states of the reactor if NH3 is of a low concentration in the exhaust.
Download or read book Assessment of Fuel Economy Technologies for Light Duty Vehicles written by National Research Council and published by National Academies Press. This book was released on 2011-06-03 with total page 373 pages. Available in PDF, EPUB and Kindle. Book excerpt: Various combinations of commercially available technologies could greatly reduce fuel consumption in passenger cars, sport-utility vehicles, minivans, and other light-duty vehicles without compromising vehicle performance or safety. Assessment of Technologies for Improving Light Duty Vehicle Fuel Economy estimates the potential fuel savings and costs to consumers of available technology combinations for three types of engines: spark-ignition gasoline, compression-ignition diesel, and hybrid. According to its estimates, adopting the full combination of improved technologies in medium and large cars and pickup trucks with spark-ignition engines could reduce fuel consumption by 29 percent at an additional cost of $2,200 to the consumer. Replacing spark-ignition engines with diesel engines and components would yield fuel savings of about 37 percent at an added cost of approximately $5,900 per vehicle, and replacing spark-ignition engines with hybrid engines and components would reduce fuel consumption by 43 percent at an increase of $6,000 per vehicle. The book focuses on fuel consumption-the amount of fuel consumed in a given driving distance-because energy savings are directly related to the amount of fuel used. In contrast, fuel economy measures how far a vehicle will travel with a gallon of fuel. Because fuel consumption data indicate money saved on fuel purchases and reductions in carbon dioxide emissions, the book finds that vehicle stickers should provide consumers with fuel consumption data in addition to fuel economy information.
Download or read book Introduction to Modeling and Control of Internal Combustion Engine Systems written by Lino Guzzella and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internal combustion engines still have a potential for substantial improvements, particularly with regard to fuel efficiency and environmental compatibility. These goals can be achieved with help of control systems. Modeling and Control of Internal Combustion Engines (ICE) addresses these issues by offering an introduction to cost-effective model-based control system design for ICE. The primary emphasis is put on the ICE and its auxiliary devices. Mathematical models for these processes are developed in the text and selected feedforward and feedback control problems are discussed. The appendix contains a summary of the most important controller analysis and design methods, and a case study that analyzes a simplified idle-speed control problem. The book is written for students interested in the design of classical and novel ICE control systems.
Download or read book EXPERIMENTAL AND MODELING STUDY OF PARTICULATE MATTER OXIDATION UNDER LOADING CONDITIONS FOR A SCR CATALYST ON A DIESEL PARTICULATE FILTER written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : The heavy-duty diesel engines use a Diesel Oxidation Catalyst (DOC), a Catalyzed Particulate Filter (CPF), a Selective Catalytic Reduction (SCR) with urea injection and a Ammonia Oxidation Catalyst (AMOX), to meet the US EPA 2010/2013 particulate matter (PM) and NOx emission standards. However, it is not possible to achieve the 2015 California low NOx standards with this arrangement. Hence, there is a need to improve the existing aftertreatment system. This can be achieved by coating the SCR catalyst on a diesel particulate filter (DPF), thus combining the PM filtration and NOx reduction functionality into a single device. This reduces the overall volume/weight of the system and provides opportunity for packaging flexibility and improved thermal management along with the possibility of higher NOx reduction with a downstream SCR system. The SCR catalyst on a DPF used in this study is known as a SCRF℗ʼ which was supplied by Johnson Matthey and Corning. Previous research on the CPF and SCRF℗ʼ at MTU highlighted that the reactivity of PM retained in the CPF and SCRF℗ʼ is higher during loading conditions compared to passive oxidation conditions i.e. when the flow rate of PM entering the CPF or SCRF℗ʼ is higher in loading conditions compared to the low flow rate and higher PM reaction rate during passive oxidation conditions. A 2013 Cummins ISB engine with a DOC-SCRF℗ʼ arrangement was used to perform twelve tests (eight tests without urea injection and four tests with urea injection) in order to determine the NO2 assisted passive oxidation performance of the SCRF℗ʼ under loading conditions with and without urea injection. The primary focus of this study was to carry out Loading Tests with and without Urea injection and measure species concentrations, PM mass retained, exhaust flowrates, substrate temperature distributions, pressure drop across the filter, and to determine the kinetics of NO2 assisted PM oxidation under loading conditions and compare it with kinetics under passive oxidation conditions. The NO2 assisted passive oxidation performance of the SCRF℗ʼ was experimentally studied by running the engine at 2400 RPM and four different loads at nominal and reduced rail pressure for 5.5 hours in two stages of loading. These conditions were intended to span the SCRF℗ʼ inlet temperatures in the range of 264-364oC and inlet NO2 concentrations in the range of 52-120 ppm. Four conditions out of these eight conditions were repeated with the injection of urea in the form of diesel exhaust fluid at a target ammonia to NOx ratio of 1.0 to investigate both the NOx reduction performance, as well as the effect of urea on the NO2 assisted passive oxidation performance. From the conclusions of the study based on the experimental data, it was found that the cumulative percentage of PM oxidized in the SCRF℗ʼ increases with the increase in engine load due to higher SCRF℗ʼ temperatures and NO2 concentrations. On average, the reactions rates with urea injection during loading conditions in the SCRF℗ʼ are 25% lower compared to the reaction rates without urea injection. The reactivity of PM under loading conditions with and without urea injection is higher compared to the reactivity of PM under passive oxidation with and without urea injection. For a lumped PM oxidation model, a higher pre-exponential for NO2 assisted oxidation is needed for loading as compared to passive oxidation conditions. It was not possible to determine the kinetics of NO2 assisted oxidation of PM under loading conditions from the experimental data using a standard Arrhenius model which lead to the development of a different model for PM oxidation. A PM oxidation model was developed based on the shrinking core model which keeps the identity of the incoming PM masses in the SCRF℗ʼ as compared to SCR-F model being developed at MTU which is lumped model for PM oxidation. The PM oxidation model was calibrated to simulate PM oxidation in the SCRF℗ʼ with a single set of kinetics under wide range of conditions including loading and passive oxidation conditions. The reaction rate results from the PM oxidation model were then applied to the SCR-F model to simulate the pressure drop across SCRF℗ʼ and the PM retained in the SCRF℗ʼ for the loading conditions used in this study. The SCR-F model was calibrated using experimental data from Loading Tests w/o Urea to simulate the PM retained within ℗ł2 g and pressure drop across SCRF℗ʼ within ℗ł0.5 kPa of the experimental data at the end of the test. The calibrated SCR-F model was also used to estimate the cake, wall and channel pressure drop and the PM retained in the cake and wall for the Loading Tests w/o Urea to check the integrity of experimental data and the consistency of the model. The NO2 assisted kinetics for PM oxidation in the SCRF℗ʼ without urea injection using the SCR-F model resulted in an activation energy of 96 kJ/gmol and pre-exponential factor of 2.6 m/K-s for the cake and 1.8 m/K-s for the wall. An analysis of the results from the SCR-F model suggests that for all the conditions, 84-92% of the total PM retained was in the PM cake layer and the oxidation in the PM cake layer accounted for 72-84% of the total PM mass oxidized during loading.
