High Egr Dilution Enabled By Dual Mode Turbulent Jet Ignition Dm Tji For High Efficiency Internal Combustion Engines

Gasoline fuel is the most convenient energy source for light-duty vehicles in energy density and refueling time. However, the emission regulations for internal combustion engines force the industry to exploit innovative combustion technologies. The spark-ignition engine was forced to be cleaner and more efficient, changing from regular combustion engines to a more advanced internal combustion engine and electrification. The current scenario shows that automotive companies and researchers are exploring hybrid powertrains with advanced internal combustion engine technologies with electrification or pure electric vehicles. The Dual Mode, Turbulent Jet Ignition (DM-TJI) system is one of the promising advanced combustion systems, powered by active air/fuel scavenging pre-chamber ignition systems. The distributed ignition sites created by the pre-chamber flames improve the combustion engine's efficiency, simultaneously mitigating combustion knock at a high engine compression ratio and enabling lean-burn or high level of external EGR dilution operation. This study analyzes the performance of a single-cylinder DM-TJI metal engine with gasoline and alternative fuels. The first part of the study presents the experimental investigations on three pre-chamber nozzle orifice diameters at various engine speeds and 10 bar engine load. The combustion parameters for each tested orifice diameter are presented for the incremental engine speeds. A numerical analysis was conducted using the GT-Power model simulation tool to support the experimental result. The DM-TJI engine's maximum gross indicated efficiency was examined and found to be 44.56%, with a higher EGR dilution rate of 45%. This orifice diameter study reported on the first published results of the desertion. Additional experimental data were collected for the selected orifice diameter at a wide range of engine operating test matrices. A predictive engine model was introduced with experimental data validation. The experimental data and predictive model generated the engine performance and fuel map for a real-world fuel economy study. Conventional and hybrid powertrain vehicles were developed with GT-Suite commercial software. Each powertrain model was calibrated in terms of components (battery, electric motors) capacity, internal combustion engine operative points, energy management strategy, and gear ratios with chassis dynamometer measured data of the vehicle drive cycle. A selected U.S. Environmental Protection Agency (EPA) driving schedule was implemented on the GT-Suite powertrain. The DM-TJI engine drive cycle fuel economy is compared to an industry-based conventional vehicle with the same powertrain except for the engine map. The results show the DM-TJI engine fuel economy improvement between 10.5%-17.29% and CO2 emissions reductions between 9.51%-14.75% for the selected driving schedule. Mild and parallel hybrid powertrain further improve the fuel economy by 9.23% and 29.88%, respectively, compared to the conventional powertrain of the DM-TJI engine. The CO2 emission was reduced by 23%. Finally, the single-cylinder DM-TJI metal engine performance under different alternative fuels was studied. An experimental test was carried out at stoichiometric conditions with different fuels, engine speed, engine load, and EGR dilution rates. Compared to gasoline fuel, E80 ethanol blend fuel produces 4.47% less CO2 and 25.75% less CO emission, and methane fuel produces 27.91% less CO2 and 57.85% less CO emission. E80 ethanol blend has the highest indicated efficiency of 45.61% with 45% EGR dilution. Methane fuel has a maximum indicated efficiency of 45.03% with 38.5% EGR dilution.

The number of vehicles powered by a source of energy other than traditional petroleum fuels will increase as time passes. However, based on current predictions, vehicles run on liquid fuels will be the major source of transportation for decades to come. Advanced combustion technologies can improve fuel economy of internal combustion (IC) engines and reduce exhaust emissions. The Dual Mode, Turbulent Jet Ignition (DM-TJI) system is an advanced, distributed combustion technology which can achieve high diesel-like thermal efficiencies at medium to high loads and potentially exceed diesel efficiencies at low-load operating conditions. The DM-TJI strategy extends the mixture flammability limits by igniting lean and/or highly dilute mixtures, leading to low-temperature combustion (LTC) modes in spark ignition (SI) engines. A novel, reduced order, and physics-based model was developed to predict the behavior of a DM-TJI engine with a pre-chamber air valve assembly. The engine model developed was calibrated based on experimental data from a Prototype II DM-TJI engine. This engine was designed, built, and tested at the MSU Energy and Automotive Research Laboratory (EARL). A predictive, generalized model was introduced to obtain a complete engine fuel map for the DM-TJI engine. The engine fuel map was generated in a four-cylinder boosted configuration under highly dilute conditions, up to 40% external exhaust gas recirculation (EGR). A vehicle simulation was then performed to further explore fuel economy gains using the fuel map generated for the DM-TJI engine. The DM-TJI engine was embodied in an industry-based vehicle to examine the behavior of the engine over the U.S. Environmental Protection Agency (EPA) driving schedules. The results obtained from the drive cycle analysis of the DM-TJI engine in an industry-based vehicle were compared to the results of the same vehicle with its original engine. The vehicle equipped with the DM-TJI system was observed to benefit from ~13% improvement in fuel economy and ~11% reduction in CO2 emission over the EPA combined city/high driving schedules. Potential improvements were discussed, as these results of the drive cycle analysis are the first-ever reported results for a DM-TJI engine embodied in an industry-based vehicle. The resulting fuel economy and CO2 emission were used to conduct a cost-benefit analysis of a DM-TJI engine. The cost-benefit analysis followed the economic and key inputs used by the U.S. EPA in a Proposed Determination prepared by that agency. The outcomes of the cost-benefit analysis for the vehicle equipped with the DM-TJI system were reported in comparison with the same vehicle with its base engine. The extra costs of a DM-TJI engine were observed to be compensated over the first three years of the vehicle's life time. The results projected maximum savings of approximately 2400 in 2019 dollars. This includes the lifetime-discounted present value of the net benefits of the DM-TJI technology, compared to the base engine examined. In this dollar saving estimate, the societal effects of CO2 emission were calculated based on values by the interagency working group (IWG) at 3% discount rate.

The international marine shipping industry is responsible for the transport of around 90% of the total world trade. Low-speed two-stroke diesel engines usually propel the largest trading ships. This engine type choice is mainly motivated by its high fuel efficiency and the capacity to burn cheap low-quality fuels. To reduce the marine freight impact on the environment, the International Maritime Organization (IMO) has introduced stricter limits on the engine pollutant emissions. One of these new restrictions, named Tier III, sets the maximum NOx emissions permitted. New emission reduction technologies have to be developed to fulfill the Tier III limits on two-stroke engines since adjusting the engine combustion alone is not sufficient. There are several promising technologies to achieve the required NOx reductions, Exhaust Gas Recirculation (EGR) is one of them. For automotive applications, EGR is a mature technology, and many of the research findings can be used directly in marine applications. However, there are some differences in marine two-stroke engines, which require further development to apply and control EGR. The number of available engines for testing EGR controllers on ships and test beds is low due to the recent introduction of EGR. Hence, engine simulation models are a good alternative for developing controllers, and many different engine loading scenarios can be simulated without the high costs of running real engine tests. The primary focus of this thesis is the development and validation of models for two-stroke marine engines with EGR. The modeling follows a Mean Value Engine Model (MVEM) approach, which has a low computational complexity and permits faster than real-time simulations suitable for controller testing. A parameterization process that deals with the low measurement data availability, compared to the available data on automotive engines, is also investigated and described. As a result, the proposed model is parameterized to two different two-stroke engines showing a good agreement with the measurements in both stationary and dynamic conditions. Several engine components have been developed. One of these is a new analytic in-cylinder pressure model that captures the influence of the injection and exhaust valve timings without increasing the simulation time. A new compressor model that can extrapolate to low speeds and pressure ratios in a physically sound way is also described. This compressor model is a requirement to be able to simulate low engine loads. Moreover, a novel parameterization algorithm is shown to handle well the model nonlinearities and to obtain a good model agreement with a large number of tested compressor maps. Furthermore, the engine model is complemented with dynamic models for ship and propeller to be able to simulate transient sailing scenarios, where good EGR controller performance is crucial. The model is used to identify the low load area as the most challenging for the controller performance, due to the slower engine air path dynamics. Further low load simulations indicate that sensor bias can be problematic and lead to an undesired black smoke formation, while errors in the parameters of the controller flow estimators are not as critical. This result is valuable because for a newly built engine a proper sensor setup is more straightforward to verify than to get the right parameters for the flow estimators.

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.

Volume 2 of the two-volume set Advanced direct injection combustion engine technologies and development investigates diesel DI combustion engines, which despite their commercial success are facing ever more stringent emission legislation worldwide. Direct injection diesel engines are generally more efficient and cleaner than indirect injection engines and as fuel prices continue to rise DI engines are expected to gain in popularity for automotive applications. Two exclusive sections examine light-duty and heavy-duty diesel engines. Fuel injection systems and after treatment systems for DI diesel engines are discussed. The final section addresses exhaust emission control strategies, including combustion diagnostics and modelling, drawing on reputable diesel combustion system research and development. Investigates how HSDI and DI engines can meet ever more stringent emission legislation Examines technologies for both light-duty and heavy-duty diesel engines Discusses exhaust emission control strategies, combustion diagnostics and modelling

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