Author: Bernard Henry Johnson (IV.) Publisher: ISBN: Category : Languages : en Pages :
Book Description
New technologies are needed to improve engine efficiencies in road-freight applications, without sacrificing power output. Heat transfer losses are one of the largest sources of inefficiency in these internal-combustion engines. Mitigating these losses creates the opportunity for substantial efficiency gains. Additionally, reduced heat transfer can allow for high-temperature combustion, which enables the use of low-cetane fuels--as well as non-petroleum-based alternative fuels--in direct-injected operation. Using these fuels can simplify the exhaust aftertreatment system. First, modeling is used to explore possible strategies for reducing heat transfer. Engine insulation, along with mechanical regeneration that utilizes increased exhaust exergy, can increase engine exergy efficiency beyond 50%. Next, experiments are performed to determine the feasibility of using alcohol direct injection to phase and control combustion in an insulated engine. Even at stoichiometric operation, engine-out soot emissions are below the 2010 EPA standard without aftertreatment. More experiments are conducted to evaluate the performance of an insulated, direct-injected, mechanically-regenerated engine. Turbocharging increases LHV efficiency to nearly 43%, and load to almost 30 bar IMEP. Turbo-compounding is shown to make modest additional gains. Finally, exhaust retention is used to reduce load by 50%--while remaining stoichiometric--at little loss of efficiency.
Author: Avinash Kumar Agarwal Publisher: Springer Nature ISBN: 9811612803 Category : Technology & Engineering Languages : en Pages : 319
Book Description
This monograph is based on methanol as a fuel for transportation sector, specifically for compression ignition (CI) engines. The contents present examples of utilization of methanol as a fuel for CI engines in different modes of transportation such as railroad, personal vehicles or heavy duty road transportation. The book also focuses on effect of methanol on combustion and performance characteristics of the engine. The effect of methanol on exhaust emission production, prediction and control is also discussed. It also discusses current methanol utilization and its potential, its effect on the engine in terms of efficiency, combustion, performance, pollutants formation and prediction. Part of the chapters are based on review of state-of-the-art while other chapters are dedicated to an original research. This volume will be a useful guide to professionals and academics involved in alternative fuels, compression ignition engines, and environmental research.
Author: Flavio Dal Forno Chuahy Publisher: ISBN: Category : Languages : en Pages : 0
Book Description
Dual fuel reactivity controlled compression ignition (RCCI) combustion is a promising method to achieve high efficiency with near zero NOx and soot emissions; however, the requirement to carry two fuels on-board has limited practical applications. Advancements in catalytic reforming have demonstrated the ability to generate syngas (a mixture of CO and hydrogen) from a single hydrocarbon stream. The reformed fuel mixture can then be used as a low reactivity fuel stream to enable RCCI out of a single parent fuel. Beyond enabling dual-fuel combustion strategies out of a single parent fuel, fuel reforming can be endothermic and allow recovery of exhaust heat to drive the reforming reactions, potentially improving overall efficiency of the system. Previous works have focused on using reformed fuel to extend the lean limit of spark ignited engines, and enhancing the control of HCCI type combustion. The strategy pairs naturally with advanced dual-fuel combustion strategies, and the use of dual-fuel strategies in the context of on-board reforming and energy recovery has not been explored. Accordingly, the work presented in this dissertation attempts to fill in the gaps in the current literature and provide a pathway to "single" fuel RCCI combustion through a combination of experiments and computational fluid dynamics modeling. Initially, a system level analysis focusing on three common reforming techniques (i.e., partial oxidation, steam reforming and auto-thermal reforming) was conducted to evaluate the potential of reformed fuel. A system layout was proposed for each reforming technique and a detailed thermodynamic analysis using first- and second-law approaches were used to identify the sources of efficiency improvements. The results showed that reformed fuel combustion with a near TDC injection of diesel fuel can increase engine-only efficiency by 4% absolute when compared to a conventional diesel baseline. The efficiency improvements were a result of reduced heat transfer and shorter, more thermodynamically efficient, combustion process. For exothermic reforming processes, losses in the reformer outweigh the improvements to engine efficiency, while for endothermic processes the recovery of exhaust energy was able to allow the system efficiency to retain a large portion of the benefits to the engine combustion. Energy flow analysis showed that the reformer temperature and availability of high grade exhaust heat were the main limiting factors preventing higher efficiencies. RCCI combustion was explored experimentally for its potential to expand on the optimization results and achieve low soot and NOx emissions. The results showed that reformed fuel can be used with diesel to enable RCCI combustion and resulted in low NOx and soot emissions while achieving efficiencies similar to conventional diesel combustion. Experiments showed that the ratio H2/(H2+CO) is an important parameter for optimal engine operation. Under part-load conditions, fractions of H2/(H2+CO) higher than 60% led to pressure oscillations inside the cylinder that substantially increased heat transfer and negated any efficiency benefits. The system analysis approach was applied to the experimental results and showed that chemical equilibrium limited operation of the engine to sub-optimal operating conditions. RCCI combustion was able to achieve "diesel like" system level efficiencies without optimization of either the engine operating conditions or the combustion system. Reformed fuel RCCI was able to provide a pathway to meeting current and future emission targets with a reduction or complete elimination of aftertreatment costs. Particle size distribution experiments showed that addition of reformed fuel had a significant impact on the shape of the particle size distribution. Addition of reformed fuel reduced accumulation-mode particle concentration while increasing nucleation-mode particles. When considering the full range of particle sizes there was a significant increase in total particle concentration. However, when considering currently regulated (Dm>23nm) particles, total concentration was comparable. To address limitations identified in the system analysis of the RCCI experiments a solid oxide fuel cell was combined with the engine into a hybrid electrochemical combustion system. The addition of the fuel cell addresses the limitations by providing sufficient high grade heat to fully drive the reforming reactions. From a system level perspective, the impact of the high frequency oscillations observed in the experiments are reduced, as the system efficiency is less dependent on the engine efficiency. From an engine perspective, the high operating pressures and low reactivity of the anode gas allow reduction of the likelihood of such events. A 0-D system level code was developed and used to find representative conditions for experimental engine validation. The results showed that the system can achieve system electrical efficiencies higher than 70% at 1 MWe power level. Experimental validation showed that the engine was able to operate under both RCCI and HCCI combustion modes and resulted in low emissions and stable combustion. The potential of a hybrid electrochemical combustion system was demonstrated for high efficiency power generation
Author: Dhananjay Kumar Srivastava Publisher: Springer ISBN: 9811075751 Category : Technology & Engineering Languages : en Pages : 346
Book Description
This book discusses all aspects of advanced engine technologies, and describes the role of alternative fuels and solution-based modeling studies in meeting the increasingly higher standards of the automotive industry. By promoting research into more efficient and environment-friendly combustion technologies, it helps enable researchers to develop higher-power engines with lower fuel consumption, emissions, and noise levels. Over the course of 12 chapters, it covers research in areas such as homogeneous charge compression ignition (HCCI) combustion and control strategies, the use of alternative fuels and additives in combination with new combustion technology and novel approaches to recover the pumping loss in the spark ignition engine. The book will serve as a valuable resource for academic researchers and professional automotive engineers alike.
Author: Giovanni Fiengo Publisher: Springer Science & Business Media ISBN: 1447144686 Category : Technology & Engineering Languages : en Pages : 86
Book Description
Progressive reductions in vehicle emission requirements have forced the automotive industry to invest in research and development of alternative control strategies. Continual control action exerted by a dedicated electronic control unit ensures that best performance in terms of pollutant emissions and power density is married with driveability and diagnostics. Gasoline direct injection (GDI) engine technology is a way to attain these goals. This brief describes the functioning of a GDI engine equipped with a common rail (CR) system, and the devices necessary to run test-bench experiments in detail. The text should prove instructive to researchers in engine control and students are recommended to this brief as their first approach to this technology. Later chapters of the brief relate an innovative strategy designed to assist with the engine management system; injection pressure regulation for fuel pressure stabilization in the CR fuel line is proposed and validated by experiment. The resulting control scheme is composed of a feedback integral action and a static model-based feed-forward action, the gains of which are scheduled as a function of fundamental plant parameters. The tuning of closed-loop performance is supported by an analysis of the phase-margin and the sensitivity function. Experimental results confirm the effectiveness of the control algorithm in regulating the mean-value rail pressure independently from engine working conditions (engine speed and time of injection) with limited design effort.
Author: Jerald A. Caton Publisher: John Wiley & Sons ISBN: 111903759X Category : Technology & Engineering Languages : en Pages : 384
Book Description
This book provides an introduction to basic thermodynamic engine cycle simulations, and provides a substantial set of results. Key features includes comprehensive and detailed documentation of the mathematical foundations and solutions required for thermodynamic engine cycle simulations. The book includes a thorough presentation of results based on the second law of thermodynamics as well as results for advanced, high efficiency engines. Case studies that illustrate the use of engine cycle simulations are also provided.
Author: Prabhat Ranjan Jha Publisher: ISBN: Category : Electronic dissertations Languages : en Pages : 313
Book Description
It's crucial to use advanced combustion strategies to increase efficiency and decrease engine-out pollutants because of the compelling need to reduce the global carbon footprint. This dissertation proposes dual fuel low-temperature combustion as a viable strategy to decrease engine-out emissions and increase the thermal efficiency of future heavy-duty internal combustion (IC) engines. In dual fuel combustion, a low reactivity fuel (e.g. methane, propane) is ignited by a high reactivity fuel (diesel) in a compression-ignited engine. Generally, the energy fraction of low reactivity fuel is maintained at much higher levels than the energy fraction of the high reactivity fuel. For a properly calibrated engine, combustion occurs at lean and low-temperature conditions (LTC). This decreases the chances of the formation of soot and oxides of nitrogen within the engine. However, at low load conditions, this type of combustion results in high hydrocarbon and carbon monoxide emissions. The first part of this research experimentally examines the effect of methane (a natural gas surrogate) substitution on early injection dual fuel combustion at representative low loads of 3.3 and 5.0 bar BMEPs in a single-cylinder compression ignition engine (SCRE). Gaseous methane fumigated into the intake manifold at various methane energy fractions was ignited using a high-pressure diesel pilot injection at 310 CAD. Cyclic combustion variations at both loads were also analyzed to obtain further insights into the combustion process and identify opportunities to further improve fuel conversion efficiencies at low load operation. In the second part, the cyclic variations in dual fuel combustion of three different low reactivity fuels (methane, propane, and gasoline) ignited using a high-pressure diesel pilot injection was examined and the challenges and opportunities in utilizing methane, propane, and gasoline in diesel ignited dual fuel combustion, as well as strategies for mitigating cyclic variations, were explored. Finally, in the third part a CFD model was created for diesel methane dual fuel LTC. The validated model was used to investigate the effect of methane on diesel autoignition and various spray targeting strategies were explored to mitigate high hydrocarbon and carbon monoxide emissions at low load conditions.
Author: Jihad Badra Publisher: Elsevier ISBN: 032388458X Category : Technology & Engineering Languages : en Pages : 262
Book Description
Artificial Intelligence and Data Driven Optimization of Internal Combustion Engines summarizes recent developments in Artificial Intelligence (AI)/Machine Learning (ML) and data driven optimization and calibration techniques for internal combustion engines. The book covers AI/ML and data driven methods to optimize fuel formulations and engine combustion systems, predict cycle to cycle variations, and optimize after-treatment systems and experimental engine calibration. It contains all the details of the latest optimization techniques along with their application to ICE, making it ideal for automotive engineers, mechanical engineers, OEMs and R&D centers involved in engine design. Provides AI/ML and data driven optimization techniques in combination with Computational Fluid Dynamics (CFD) to optimize engine combustion systems Features a comprehensive overview of how AI/ML techniques are used in conjunction with simulations and experiments Discusses data driven optimization techniques for fuel formulations and vehicle control calibration
Author: Institution of Mechanical Engineers Publisher: Elsevier ISBN: 0857096044 Category : Technology & Engineering Languages : en Pages : 348
Book Description
This book presents the papers from the latest conference in this successful series on fuel injection systems for internal combustion engines. It is vital for the automotive industry to continue to meet the demands of the modern environmental agenda. In order to excel, manufacturers must research and develop fuel systems that guarantee the best engine performance, ensuring minimal emissions and maximum profit. The papers from this unique conference focus on the latest technology for state-of-the-art system design, characterisation, measurement, and modelling, addressing all technological aspects of diesel and gasoline fuel injection systems. Topics range from fundamental fuel spray theory, component design, to effects on engine performance, fuel economy and emissions. Presents the papers from the IMechE conference on fuel injection systems for internal combustion engines Papers focus on the latest technology for state-of-the-art system design, characterisation, measurement and modelling; addressing all technological aspects of diesel and gasoline fuel injection systems Topics range from fundamental fuel spray theory and component design to effects on engine performance, fuel economy and emissions
Author: Bernard Henry Johnson (IV.)
Author: Bernard Johnson
Author: Avinash Kumar Agarwal
Author: Flavio Dal Forno Chuahy
Author: Dhananjay Kumar Srivastava
Author: Giovanni Fiengo
Author: Jerald A. Caton
Author: Prabhat Ranjan Jha
Author: Jihad Badra
Author: Institution of Mechanical Engineers