OPTIMIZATION AND COMPARISON OF OVER-EXPANDED AND OTHER HIGH EFFICIENCY FOUR-STROKE SPARK-IGNITED BOOSTED ENGINES PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download OPTIMIZATION AND COMPARISON OF OVER-EXPANDED AND OTHER HIGH EFFICIENCY FOUR-STROKE SPARK-IGNITED BOOSTED ENGINES PDF full book. Access full book title OPTIMIZATION AND COMPARISON OF OVER-EXPANDED AND OTHER HIGH EFFICIENCY FOUR-STROKE SPARK-IGNITED BOOSTED ENGINES by . Download full books in PDF and EPUB format.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Abstract : Recent fuel economy and emission regulations are the major concern of the research and development of modern internal combustion engine. Such technologies include variable valve timing (VVT), direct injection (DI), turbocharging, downsizing, and over-expanded cycle are used by many manufacturers to improve engine fuel economy or increase power density. Current Atkinson cycle technology in the production engine is mainly realized by an advanced valvetrain system to reduce the effective compression ratio while maintaining the same expansion ratio. Another approach to realize over-expanded cycle engine is to utilize a multi-link cranktrain mechanism. Although the Atkinson cycle was originally patented in the 1880s, the research of the over-expanded cycle engine realized by a multi-link cranktrain design is incomplete. This study focuses on the investigation of over-expanded engine realized by a cranktrain with a multi-link mechanism. The multi-link mechanism of cranktrain was developed and simulated with the constraints of packaging and match the same specification as the baseline engine including compression ratio, bore, and intake/compression stroke. This study also discusses adapting the cam profiles, cam phasing, and spark timing to compensate for the geometric characteristics difference between an Atkinson cycle engine and a conventional engine. The 1-D engine model was developed and calibrated in the commercial engine program, GT-Suite/GT-Power, based on the experimental results from a production four-cylinder spark-ignited engine (not over-expanded). The simulations of multi-link over-expanded engine and high compression engine were realized by substituting the new cranktrain for the baseline cranktrain In this study, the investigation of the multi-link over-expanded engine included a series of operating conditions from light load to high load. The results were compared at the optimized condition between the baseline engine, multi-link over-expand engine, and high compression engine. At the light load condition, it was observed that the net indicated efficiency of the over-expanded engine was slightly improved based on the adjustment method. This study also investigated the operating condition of the baseline engine with knock constrained and exhaust temperature constrained conditions at medium to high load. With the optimization, the over-expanded cycle engine is less constrained than the baseline engine due to the reduced knock propensity and exhaust gas temperature resulting in the further improvement of net indicated efficiency. The study of the multi-link over-expanded cycle engine includes the comparison with the latest production high compression ratio engine, representing state-of-the-art high efficiency engine technologies. The net indicated efficiency of multi-link over-expanded engine is even better than the peak efficiency point of the high compression engine.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Abstract : Recent fuel economy and emission regulations are the major concern of the research and development of modern internal combustion engine. Such technologies include variable valve timing (VVT), direct injection (DI), turbocharging, downsizing, and over-expanded cycle are used by many manufacturers to improve engine fuel economy or increase power density. Current Atkinson cycle technology in the production engine is mainly realized by an advanced valvetrain system to reduce the effective compression ratio while maintaining the same expansion ratio. Another approach to realize over-expanded cycle engine is to utilize a multi-link cranktrain mechanism. Although the Atkinson cycle was originally patented in the 1880s, the research of the over-expanded cycle engine realized by a multi-link cranktrain design is incomplete. This study focuses on the investigation of over-expanded engine realized by a cranktrain with a multi-link mechanism. The multi-link mechanism of cranktrain was developed and simulated with the constraints of packaging and match the same specification as the baseline engine including compression ratio, bore, and intake/compression stroke. This study also discusses adapting the cam profiles, cam phasing, and spark timing to compensate for the geometric characteristics difference between an Atkinson cycle engine and a conventional engine. The 1-D engine model was developed and calibrated in the commercial engine program, GT-Suite/GT-Power, based on the experimental results from a production four-cylinder spark-ignited engine (not over-expanded). The simulations of multi-link over-expanded engine and high compression engine were realized by substituting the new cranktrain for the baseline cranktrain In this study, the investigation of the multi-link over-expanded engine included a series of operating conditions from light load to high load. The results were compared at the optimized condition between the baseline engine, multi-link over-expand engine, and high compression engine. At the light load condition, it was observed that the net indicated efficiency of the over-expanded engine was slightly improved based on the adjustment method. This study also investigated the operating condition of the baseline engine with knock constrained and exhaust temperature constrained conditions at medium to high load. With the optimization, the over-expanded cycle engine is less constrained than the baseline engine due to the reduced knock propensity and exhaust gas temperature resulting in the further improvement of net indicated efficiency. The study of the multi-link over-expanded cycle engine includes the comparison with the latest production high compression ratio engine, representing state-of-the-art high efficiency engine technologies. The net indicated efficiency of multi-link over-expanded engine is even better than the peak efficiency point of the high compression engine.
Author: F. Zhao
Publisher: Elsevier
ISBN: 008055279X
Category : Technology & Engineering
Languages : en
Pages : 129
Get Book Here
Book Description
The process of fuel injection, spray atomization and vaporization, charge cooling, mixture preparation and the control of in-cylinder air motion are all being actively researched and this work is reviewed in detail and analyzed. The new technologies such as high-pressure, common-rail, gasoline injection systems and swirl-atomizing gasoline fuel injections are discussed in detail, as these technologies, along with computer control capabilities, have enabled the current new examination of an old objective; the direct-injection, stratified-charge (DISC), gasoline engine. The prior work on DISC engines that is relevant to current GDI engine development is also reviewed and discussed. The fuel economy and emission data for actual engine configurations have been obtained and assembled for all of the available GDI literature, and are reviewed and discussed in detail. The types of GDI engines are arranged in four classifications of decreasing complexity, and the advantages and disadvantages of each class are noted and explained. Emphasis is placed upon consensus trends and conclusions that are evident when taken as a whole; thus the GDI researcher is informed regarding the degree to which engine volumetric efficiency and compression ratio can be increased under optimized conditions, and as to the extent to which unburned hydrocarbon (UBHC), NOx and particulate emissions can be minimized for specific combustion strategies. The critical area of GDI fuel injector deposits and the associated effect on spray geometry and engine performance degradation are reviewed, and important system guidelines for minimizing deposition rates and deposit effects are presented. The capabilities and limitations of emission control techniques and after treatment hardware are reviewed in depth, and a compilation and discussion of areas of consensus on attaining European, Japanese and North American emission standards presented. All known research, prototype and production GDI engines worldwide are reviewed as to performance, emissions and fuel economy advantages, and for areas requiring further development. The engine schematics, control diagrams and specifications are compiled, and the emission control strategies are illustrated and discussed. The influence of lean-NOx catalysts on the development of late-injection, stratified-charge GDI engines is reviewed, and the relative merits of lean-burn, homogeneous, direct-injection engines as an option requiring less control complexity are analyzed.
Author: National Research Council
Publisher: National Academies Press
ISBN: 0309216389
Category : Science
Languages : en
Pages : 373
Get Book Here
Book Description
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.
Author: Gordon Blair
Publisher: SAE International
ISBN: 0768025540
Category : Technology & Engineering
Languages : en
Pages : 847
Get Book Here
Book Description
This book provides design assistance with the actual mechanical design of an engine in which the gas dynamics, fluid mechanics, thermodynamics, and combustion have been optimized so as to provide the required performance characteristics such as power, torque, fuel consumption, or noise emission.
Author: Flavio Dal Forno Chuahy
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
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: National Research Council
Publisher: National Academies Press
ISBN: 0309159474
Category : Science
Languages : en
Pages : 251
Get Book Here
Book Description
Technologies and Approaches to Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles evaluates various technologies and methods that could improve the fuel economy of medium- and heavy-duty vehicles, such as tractor-trailers, transit buses, and work trucks. The book also recommends approaches that federal agencies could use to regulate these vehicles' fuel consumption. Currently there are no fuel consumption standards for such vehicles, which account for about 26 percent of the transportation fuel used in the U.S. The miles-per-gallon measure used to regulate the fuel economy of passenger cars. is not appropriate for medium- and heavy-duty vehicles, which are designed above all to carry loads efficiently. Instead, any regulation of medium- and heavy-duty vehicles should use a metric that reflects the efficiency with which a vehicle moves goods or passengers, such as gallons per ton-mile, a unit that reflects the amount of fuel a vehicle would use to carry a ton of goods one mile. This is called load-specific fuel consumption (LSFC). The book estimates the improvements that various technologies could achieve over the next decade in seven vehicle types. For example, using advanced diesel engines in tractor-trailers could lower their fuel consumption by up to 20 percent by 2020, and improved aerodynamics could yield an 11 percent reduction. Hybrid powertrains could lower the fuel consumption of vehicles that stop frequently, such as garbage trucks and transit buses, by as much 35 percent in the same time frame.
Author: Jeff Hartman
Publisher: Motorbooks
ISBN: 1610590368
Category : Transportation
Languages : en
Pages : 272
Get Book Here
Book Description
Drawing on a wealth of knowledge and experience and a background of more than 1,000 magazine articles on the subject, engine control expert Jeff Hartman explains everything from the basics of engine management to the building of complicated project cars. Hartman has substantially updated the material from his 1993 MBI book Fuel Injection (0-879387-43-2) to address the incredible developments in automotive fuel injection technology from the past decade, including the multitude of import cars that are the subject of so much hot rodding today. Hartman's text is extremely detailed and logically arranged to help readers better understand this complex topic.
Author: Alejandro Medina
Publisher: Springer
ISBN: 9781447152903
Category : Science
Languages : en
Pages : 195
Get Book Here
Book Description
Based on the simulations developed in research groups over the past years, Introduction to Quasi-dimensional Simulation of Spark Ignition Engines provides a compilation of the main ingredients necessary to build up a quasi-dimensional computer simulation scheme. Quasi-dimensional computer simulation of spark ignition engines is a powerful but affordable tool which obtains realistic estimations of a wide variety of variables for a simulated engine keeping insight the basic physical and chemical processes involved in the real evolution of an automotive engine. With low computational costs, it can optimize the design and operation of spark ignition engines as well as it allows to analyze cycle-to-cycle fluctuations. Including details about the structure of a complete simulation scheme, information about what kind of information can be obtained, and comparisons of the simulation results with experiments, Introduction to Quasi-dimensional Simulation of Spark Ignition Engines offers a thorough guide of this technique. Advanced undergraduates and postgraduates as well as researchers in government and industry in all areas related to applied physics and mechanical and automotive engineering can apply these tools to simulate cyclic variability, potentially leading to new design and control alternatives for lowering emissions and expanding the actual operation limits of spark ignition engines
Author: Robert A. Hintermister
Publisher:
ISBN:
Category :
Languages : en
Pages : 37
Get Book Here
Book Description
Author: Theodore Taylor
Publisher:
ISBN:
Category : Automobiles
Languages : en
Pages : 96
Get Book Here
Book Description
