Download or read book Strategies for Optimization of Diesel ignited Propane Dual Fuel Combustion in a Heavy Duty Compression Ignition Engine written by Chad Duane Carpenter and published by . This book was released on 2013 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: A 12.9 L heavy duty compression ignition engine was tested with strategies for dual fuel optimization. The effects of varied intake manifold pressure as well as split-injection strategies at a load of 5 bar BMEP and 85 PES were observed. These results were used to allow testing of split-injection strategies at a higher load of 10 bar BMEP at 70 PES that were void of MPRR above 2000 kPa/CAD. The split-injection strategies at 5 bar BMEP showed that lower BSNOx can be achieved with minimal drop in FCE. Varying intake manifold pressure revealed that combustion occurs earlier in a cycle with increasing intake manifold pressure and indirectly increasing FCE. A load of 10 bar BMEP at 70 PES should only use split-injection strategy to maintain load without high MPRR as efficiency drops with dependency on the second injection.

Download or read book Detailed Characterization of Conventional and Low Temperature Dual Fuel Combustion in Compression Ignition Engines written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this study is to assess conventional and low temperature dual fuel combustion in light- and heavy-duty multi-cylinder compression ignition engines in terms of combustion characterization, performance, and emissions. First, a light-duty compression ignition engine is converted to a dual fuel engine and instrumented for in-cylinder pressure measurements. The primary fuels, methane and propane, are each introduced into the system by means of fumigation before the turbocharger, ensuring the air-fuel composition is well-mixed. Experiments are performed at 2.5, 5, 7.5, and 10 bar BMEP at an engine speed of 1800 RPM. Heat release analyses reveal that the ignition delay and subsequent combustion processes are dependent on the primary fuel type and concentration, pilot quantity, and loading condition. At low load, diesel-ignited propane yields longer ignition delay periods than diesel-ignited methane, while at high load the reactivity of propane is more pronounced, leading to shorter ignition delays. At high load (BMEP = 10 bar), the rapid heat release associated with diesel-ignited propane appears to occur even before pilot injection, possibly indicating auto-ignition of the propane-air mixture. Next, a modern, heavy-duty compression ignition engine is commissioned with an open architecture controller and instrumented for in-cylinder pressure measurements. Initial diesel-ignited propane dual fuel experiments (fumigated before the turbocharger) at 1500 RPM reveal that the maximum percent energy substitution (PES) of propane is limited to 86, 60, 33, and 25 percent at 5, 10, 15, and 20 bar BMEP, respectively. Fueling strategy, injection strategy, exhaust gas recirculation (EGR) rate, and intake boost pressure are varied in order to maximize the PES of propane at 10 bar BMEP, which increases from 60 PES to 80 PES of propane. Finally, diesel-ignited propane dual fuel low temperature combustion (LTC) is implemented using early injection timings (50 DBTDC) at 5 bar BMEP. A sweep of injection timings from 10 DBTDC to 50 DBTDC reveals the transition from conventional to low temperature dual fuel combustion, indicated by ultra-low NOx̳ and smoke emissions. Optimization of the dual fuel LTC concept yields less than 0.02 g/kW-hr NOx̳ and 0.06 FSN smoke at 93 PES of propane.

Download or read book Exploration of High Efficiency Pathways in Dual Fuel Low Temperature Combustion Engines written by Prabhat Ranjan Jha and published by . This book was released on 2020 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Emissions Optimization of Propane Dual Fuel Combustion Ignited by Diesel and Polyoxymethylene Dimethyl Ether At Low Loads written by Prabhat R Jha and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dual fuel engines utilize two different fuels consisting of a high reactivity fuel (HRF)injected into the cylinder and a low reactivity fuel (LRF), typically fumigated into the intakemanifold. In order to reduce the emissions of nitrogen oxides when compared against dieselcombustion, dual fuel engines begin the injection process early in the combustion cycle.However, at early injection timings dual fuel engines exhibit high emissions of both unburnedhydrocarbons (HC) and carbon monoxide (CO). This work discusses the emissions optimizationprocess to reduce emissions for two different fueling types, diesel-propane and poly-oxymethylene dimethyl ether (POMDME)-propane, on a single cylinder research engine (SCRE)based upon a PACCAR MX-11 heavy-duty engine while maintaining combustion and fuelconversion efficiencies.The parameters swept during this optimization process include start of injection, percentenergy substitution, a second injection and its timing, the split ratio - or the ratio of commandedduration of the first injection to that of the second, a coupled injection sweep, rail pressure, andintake pressure. These parameters were varied at a fixed gross indicated mean effective pressure(IMEPg) of 5 bar to represent low load operation as well as a fixed engine speed of 1339 rpm("B speed" of the SCRE). During all experiments a global limit of 1 g/kWh was set on theindicated specific NOx emissions, as well as a maximum pressure rise rate of 10 bar/deg, and acoefficient of variation of IMEPg at or below 5%. Using these limits and the emissions tradeoffsbetween HC, CO and NOx, this work was able to demonstrate diesel-propane emissionsimprovements of HC and CO of 86.4% and 66.8% respectively when compared to the baseline, while POMDME-propane emissions showed improvements in HC and CO of 90.9% and 86.2%respectively. Additionally, POMDME emissions demonstrated zero measurable filter smokenumber during all engine operations. A preliminary life cycle analysis of using both dual fuelcombinations have been compared against traditional diesel operation as well as battery poweredoperation and is found within the appendix of this work.

Download or read book Advances in Compression Ignition Natural Gas Diesel Dual Fuel Engines written by Hongsheng Guo and published by Frontiers Media SA. This book was released on 2021-03-23 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Strategies for Reduced Unburned Hydrocarbon and Carbon Monoxide Emissions in Diesel Propane Dual Fuel Low Temperature Combustion written by Kyle Anthony Hodges and published by . This book was released on 2016 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present manuscript discusses the use of two diesel injections in diesel-ignited propane dual fuel Low Temperature Combustion (LTC). Using propane fumigation into the intake runners of a single cylinder research engine, the maximum and minimum percent energy substitution (PES) values were obtained to be 90% and 53%, respectively at 3.3 bar BMEP. An optimal PES value of 80% was used to explore the effects of a secondary injection on the engine-out emissions. The secondary injection proved to have a strong influence on combustion phasing (CA50). As combustion is phased closer to TDC the IFCE shows and increase of 4% at 5 bar BMEP and 6% at 3.3 bar BMEP. Finally, a relationship between the IFCE and the CO to CO2 conversion was developed. An increase in the carbon to hydrogen ratio of the fuel shows a reduction of the CO output of the engine while the CO2 concentration increases. More importantly however, the CO to CO2 conversion shows a direct effect on the IFCE. It is shown that a decrease in CO emissions found in the engine-out emissions will correlate directly with an increase in the IFCE.

Download or read book Analysis of Ignition Behavior in a Turbocharged Direct Injection Dual Fuel Engine Using Propane and Methane as Primary Fuels written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents experimental analyses of the ignition delay (ID) behavior for diesel-ignited propane and diesel-ignited methane dual fuel combustion. Two sets of experiments were performed at a constant speed (1800 rev/min) using a 4-cylinder direct injection diesel engine with the stock ECU and a wastegated turbocharger. First, the effects of fuel-air equivalence ratios (© pilot ¼ 0.2-0.6 and © overall ¼ 0.2-0.9) on IDs were quantified. Second, the effects of gaseous fuel percent energy substitution (PES) and brake mean effective pressure (BMEP) (from 2.5 to 10 bar) on IDs were investigated. With constant © pilot (> 0.5), increasing © overall with propane initially decreased ID but eventually led to premature propane autoignition; however, the corresponding effects with methane were relatively minor. Cyclic variations in the start of combustion (SOC) increased with increasing © overall (at constant © pilot), more significantly for propane than for methane. With increasing PES at constant BMEP, the ID showed a nonlinear (initially increasing and later decreasing) trend at low BMEPs for propane but a linearly decreasing trend at high BMEPs. For methane, increasing PES only increased IDs at all BMEPs. At low BMEPs, increasing PES led to significantly higher cyclic SOC variations and SOC advancement for both propane and methane. Finally, the engine ignition delay (EID) was also shown to be a useful metric to understand the influence of ID on dual fuel combustion.

Download or read book Optimization Methods for the Mixture Formation and Combustion Process in Diesel Engines written by Jost Weber and published by Cuvillier Verlag. This book was released on 2008 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book EXPERIMENTAL AND COMPUTATIONAL INVESTIGATION OF DUAL FUEL DIESEL NATURAL GAS RCCI COMBUSTION IN A HEAVY DUTY DIESEL ENGINE written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : Among the various alternative fuels, natural gas is considered as a leading candidate for heavy-duty applications due to its availability and applicability in conventional internal combustion diesel engines. Compared to their diesel counterparts natural gas fueled spark-ignited engines have a lower power density, reduced low-end torque capability, limited altitude performance, and ammonia emissions downstream of the three-way catalyst. The dual fuel diesel/natural gas engine does not suffer with the performance limitations of the spark-ignited concept due to the flexibility of switching between different fueling modes. Considerable research has already been conducted to understand the combustion behavior of dual fuel diesel/natural gas engines. As reported by most researchers, the major difficulty with dual fuel operation is the challenge of providing high levels of natural gas substitution, especially at low and medium loads. In this study extensive experimental and simulation studies were conducted to understand the combustion behavior of a heavy-duty diesel engine when operated with compressed natural gas (CNG) in a dual fuel regime. In one of the experimental studies, conducted on a 13 liter heavy-duty six cylinder diesel engine with a compression ratio of 16.7:1, it was found that at part loads high levels of CNG substitution could be achieved along with very low NOx and PM emissions by applying reactivity controlled compression ignition (RCCI) combustion. When compared to the diesel-only baseline, a 75% reduction in both NOx and PM emissions was observed at a 5 bar BMEP load point along with comparable fuel consumption values. Further experimental studies conducted on the 13 liter heavy-duty six cylinder diesel engine have shown that RCCI combustion targeting low NOx emissions becomes progressively difficult to control as the load is increased at a given speed or the speed is reduced at a given load. To overcome these challenges a number of simulation studies were conducted to quantify the in-cylinder conditions that are needed at high loads and low to medium engine speeds to effectively control low NOx RCCI combustion. A number of design parameters were analyzed in this study including exhaust gas recirculation (EGR) rate, CNG substitution, injection strategy, fuel injection pressure, fuel spray angle and compression ratio. The study revealed that lowering the compression ratio was very effective in controlling low NOx RCCI combustion. By lowering the base compression ratio by 4 points, to 12.7:1, a low NOx RCCI combustion was achieved at both 12 bar and 20 bar BMEP load points. The NOx emissions were reduced by 75% at 12 bar BMEP while fuel consumption was improved by 5.5%. For the 20 BMEP case, a 2% improvement in fuel consumption was achieved with an 87.5% reduction in NOx emissions. At both load points low PM emissions were observed with RCCI combustion. A low NOx RCCI combustion system has multiple advantages over other combustion approaches, these include; significantly lower NOx and PM emission which allows a reduction in aftertreatment cost and packaging requirements along with application of higher CNG substitution rates resulting in reduced CO2 emissions.

Download or read book Analysis and Control of Compression ignition and Spark ignited Engines Operating with Dual fuel Combustion Strategy written by Mateos Kassa and published by . This book was released on 2017 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low temperature Combustion and Autoignition written by M.J. Pilling and published by Elsevier. This book was released on 1997-11-27 with total page 823 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combustion has played a central role in the development of our civilization which it maintains today as its predominant source of energy. The aim of this book is to provide an understanding of both fundamental and applied aspects of low-temperature combustion chemistry and autoignition. The topic is rooted in classical observational science and has grown, through an increasing understanding of the linkage of the phenomenology to coupled chemical reactions, to quite profound advances in the chemical kinetics of both complex and elementary reactions. The driving force has been both the intrinsic interest of an old and intriguing phenomenon and the centrality of its applications to our economic prosperity. The volume provides a coherent view of the subject while, at the same time, each chapter is self-contained.

Download or read book Alternative Fuels and Advanced Vehicle Technologies for Improved Environmental Performance written by Richard Folkson and published by Woodhead Publishing. This book was released on 2022-07-27 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alternative Fuels and Advanced Vehicle Technologies for Improved Environmental Performance: Towards Zero Carbon Transportation, Second Edition provides a comprehensive view of key developments in advanced fuels and vehicle technologies to improve the energy efficiency and environmental impact of the automotive sector. Sections consider the role of alternative fuels such as electricity, alcohol and hydrogen fuel cells, as well as advanced additives and oils in environmentally sustainable transport. Other topics explored include methods of revising engine and vehicle design to improve environmental performance and fuel economy and developments in electric and hybrid vehicle technologies. This reference will provide professionals, engineers and researchers of alternative fuels with an understanding of the latest clean technologies which will help them to advance the field. Those working in environmental and mechanical engineering will benefit from the detailed analysis of the technologies covered, as will fuel suppliers and energy producers seeking to improve the efficiency, sustainability and accessibility of their work. - Provides a fully updated reference with significant technological advances and developments in the sector - Presents analyses on the latest advances in electronic systems for emissions control, autonomous systems, artificial intelligence and legislative requirements - Includes a strong focus on updated climate change predictions and consequences, helping the reader work towards ambitious 2050 climate change goals for the automotive industry

Download or read book Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy Duty Vehicles written by National Research Council and published by National Academies Press. This book was released on 2010-07-30 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Addressing the Challenges of Advanced Compression Ignition Strategies Using Optimization Techniques with Machine Learning written by Naga Krishna Chaitanya Kavuri and published by . This book was released on 2018 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced compression ignition strategies like reactivity controlled compression ignition (RCCI) and gasoline compression ignition (GCI) have received substantial interest over the past few years. This is due to their potential to achieve reduced emissions, and higher efficiency, relative to conventional diesel combustion. However, most of the benefits seen in past research from these strategies were demonstrated under mid-load conditions. For these strategies to be implemented practically, similar benefits must be demonstrated across the drive cycle. Two particularly challenging areas of operation are high-load-low-speed and low-load-high-speed. Very limited research has been done with advanced compression ignition strategies in these points of the engine operating map. The reason for this is, at these operating conditions, there exists a mismatch between engine and chemistry time scales. The time scale mismatch results in either increased pressure rise rates or high levels of incomplete combustion, both of which make it difficult to operate. The work presented in this dissertation attempts to fill in these research gaps by using a combination of computational fluid dynamics modeling and genetic algorithm optimization. Initially, targeting high-load-low-speed conditions, a computational optimization study was performed at 20 bar indicated mean effective pressure and 1300 rev/min. with RCCI and GCI combustion strategies. The study was performed on a low compression ratio (12:1) piston with a "bathtub" geometry, since it was found to be well suited for high-load operation in earlier studies. The optima from the two combustion strategies were compared in terms of combustion characteristics, combustion control, and sensitivity to operating parameter variations. The results showed that both the strategies have similar combustion characteristics, including a two-stage heat release. A near top dead center injection initiated the combustion and its injection timing could be used to control the combustion phasing for both the strategies. Both the strategies required elevated levels of exhaust gas recirculation (EGR) (~55%) at a near stoichiometric global equivalence ratio to control the peak pressure rise rate. This resulted in high sensitivity to variations in EGR. To address this issue, high-load strategies at reduced EGR levels were investigated. A constraint analysis was performed using the optimization data to identify the constraints preventing operation at lower EGR levels. Results showed that operation at lower EGR rates was constrained by NOx emissions. Relaxing the NOx constraint enabled lower EGR operation with significant efficiency improvement. Allowing NOx emissions to increase to acceptable levels for selective catalytic reduction after treatment yielded an optimum at a moderate (~45%) level of EGR and a globally lean equivalence ratio of 0.8. This optimum case had near zero soot emissions and a higher net fluid efficiency (which accounted for the pumping loop work and the diesel exhaust fluid mass required to reduce the NOx emissions) compared to the earlier high EGR optima. Furthermore, the optimum case with NOx aftertreatment was compared with the high EGR optima in terms of combustion control and stability to operating condition fluctuations. The optimum with NOx aftertreatment retained the excellent combustion control seen with the high EGR optima, while reducing the sensitivity to operating parameter variations. The improved stability was attributed to operation at a reduced global equivalence ratio (from 0.93 to 0.8), which decreased the sensitivity to fluctuations in EGR rate. After addressing the issues at the high-load-low-speed operating condition, a low-load-high-speed operating point of 2 bar and 1800 rev/min. was simulated on the same engine used for the high-load studies. The results showed poor thermal efficiency for the low-load point. The poor efficiency was found to be due to an elevated level of incomplete combustion, which was a result of the low compression ratio piston used for the study. This result suggested that an optimum compression ratio should be identified considering the performance at the low-load and high-load conditions simultaneously. In addition, past optimization studies performed at low-load conditions have shown that the optimum bowl and injector design are very different compared to the high-load conditions. Accordingly, an optimization study was performed, considering performance at low- and high-load simultaneously. The optimum from the study was a stepped bowl geometry, with a compression ratio of 13.1:1, which resulted in a gross indicated efficiency of ~46% at both the loads. The study showed that the optimum design obtained from prioritizing one load deteriorates the performance at the other load. The results highlight the importance of considering multiple modes of the drive cycle simultaneously, when optimizing the engine design for advanced combustion strategies. It was shown that multiple modes of the drive cycle should be considered in optimization studies for advanced combustion strategies; however, the optimization with just two operating points took three months to complete. To consider all the modes of a drive cycle in the optimization, the computational time must be reduced. To address this issue, machine learning through Gaussian process regression was coupled with a genetic algorithm optimization to speed up the optimization process. Including machine learning within the optimization process reduced the computational time of optimization by 62%. The optimization process was further improved by using the Gaussian process regression model to check for the sensitivity of the designs to operating parameter variations during the optimization. The approach was tested with existing optimization data and it was shown that adding the stability check resulted in a reliable and stable optimum solution.

Download or read book Investigation of Two Low Emissions Strategies for Diesel Engines written by Sang-Suk Lee and published by . This book was released on 2006 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Investigation of Dual injection Strategies on Diesel methane Dual fuel Low Temperature Combustion in a Single Cylinder Research Engine written by Aamir Sohail and published by . This book was released on 2015 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present manuscript discusses the performance and emission benefits due to two diesel injections in diesel-ignited methane dual fuel Low Temperature Combustion (LTC). A Single Cylinder Research Engine (SCRE) adapted for diesel-ignited methane dual fuelling was operated at 1500 rev/min and 5 bar BMEP with 1.5 bar intake manifold pressure. The first injection was fixed at 310 CAD. A 2nd injection sweep timing was performed to determine the best 2nd injection timing (as 375 CAD) at a fixed Percentage Energy Substitution (PES 75%). The motivation to use a second late injection ATDC was to oxidize Unburnt Hydrocarbons (HC) generated from the dual fuel combustion of first injection. Finally, an injection pressure sweep (550-1300 bar) helped achieve simultaneous reduction of HC (56%) and CO (43%) emissions accompanied with increased IFCE (10%) and combustion efficiency (12%) w.r.t. the baseline single injection (at 310 CAD) of dual fuel LTC.

Download or read book Combustion in a Natural Gas diesel Fuel Dual fuel Compression Ignition Engine written by John Thomas Kubesh and published by . This book was released on 1991 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: