Criteria

Text:
Display:

Results

Viewing 1 to 30 of 552
2016-04-05
Technical Paper
2016-01-0728
Daniel Christopher Bitsis, Charles Roberts, Jason Miwa, Christopher Chadwell, Sankar Rengarajan
There are numerous off road diesel engine applications. In some applications there is more focus on metrics such as initial cost, packing and transient response and less emphasis on fuel economy. In this paper a combustion concept is presented that may be well suited to these applications. The novel combustion concept operates in two distinct operation modes: lean operation at light engine loads and stoichiometric operation at intermediate and high engine loads. One advantage to the two mode approach is the ability to simplify the aftertreatment and reduce cost. The simplified aftertreatment system utilizes a non-catalyzed diesel particulate filter (DPF) and a relatively small lean NOx trap (LNT). Under stoichiometric operation the LNT has the ability to act as a three way catalyst (TWC) for excellent control of HC, CO and NOx.
2016-04-05
Technical Paper
2016-01-0907
Matthew Blanks, Nathan Forster
In 2012, NHTSA and EPA extended Corporate Average Fuel Economy (CAFE) standards for light duty vehicles through the 2025 model year. The new standards require passenger cars to achieve an average of five percent annual improvement in fuel economy and light trucks to achieve three percent. This yearly increase in fuel economy standards and the increasing price of oil are driving research and development into fuel-saving technologies. A large portion of the current research is focused on incremental improvements in fuel economy through technologies such as new lubricant formulations. While these technologies typically yield less than two percent improvement, the gains are extremely significant and will play an increasing role in the overall effort to increase fuel economy. The ability to measure small, but statistically significant, changes in vehicle fuel economy is vital to the development of new technologies.
2016-04-05
Technical Paper
2016-01-0989
Scott Eakle, Svitlana Kroll, Alice Yau, John Gomez, Cary Henry
Ideally, complete thermal decomposition of urea should produce only two products in active Selective Catalytic Reduction (SCR) systems: ammonia and carbon dioxide. In reality, urea thermal decomposition reaction is a two-step process that includes the formation of ammonia and isocyanic acid as intermediate products. Being highly reactive, isocyanic acid can initiate the formation of larger molecular weight compounds such as cyanuric acid, biuret, melamine, ammeline, ammelide, and dicyandimide. These compounds can be responsible for the formation of deposits on the walls of the decomposition reactor in urea SCR systems. Composition of these deposits varies with temperature exposure, and under certain conditions can create oligomers such as melam, melem, and melon that are difficult to remove from exhaust pipes. Deposits can affect efficiency of the urea decomposition, and if large enough, can inhibit the exhaust flow.
2016-04-05
Technical Paper
2016-01-0636
Kevin L. Hoag, Anthony Megel
The objective of this work was to develop a methodology to assess comparative intake port designs for their capability to produce tumble flow in spark-ignition engine combustion chambers. A literature review and prior work with a steady-flow cylinder head test bench led to the conclusion that existing approaches fell far short of that needed. In creating intake ports to optimize tumble characteristics, engine development engineers have had to adopt resource-intensive approaches such as particle velocity measurements in engines with optical access, or computationally detailed, moving piston, three-dimensional finite element modeling. There have been a number of efforts to generate a “tumble number” or “tumble ratio” from steady-state cylinder head flow benches. These efforts have been loosely based on the previous development of “swirl numbers” or swirl ratios.” Steady-state bench measurements of swirl are well established, and correlate quite well to engine test results.
2016-04-05
Technical Paper
2016-01-0660
Thomas Reinhart, Marc Megel
This paper describes the potential for for the use of Dedicated EGR® (D-EGR®) in a gasoline powered medium truck engine. The project goal was to determine if it is possible to match the thermal efficiency of a medium-duty diesel engine in Class 4 to Class 7 truck operations. The project evaluated a range of parameters for a D-EGR engine, including displacement, operating speed range, boosting systems, and BMEP levels. The engine simulation was done in GT-POWER, guided by experimental experience with smaller size D-EGR engines. The resulting engine fuel consumption maps were applied to two vehicle models, which ran over a range of 8 duty cycles at 3 payloads. This allowed a thorough evaluation of how D-EGR and conventional gasoline engines compare in fuel consumption and thermal efficiency to a diesel. The project results show that D-EGR gasoline engines can compete with medium duty diesel engines in terms of both thermal efficiency and GHG emissions.
2016-04-05
Technical Paper
2016-01-0779
Radu Florea, Gary D. Neely, Zainal Abidin, Jason Miwa
For the US market, recent green-house gas (GHG) regulations coupled with ample supply of natural gas (NG) have spurred renewed interest in dual-fuel combustion regimes. This paper explores the potential of co-direct injection to improve the efficiency and reduce the methane emissions versus equivalent fumigated dual-fuel combustion systems. Using the Westport HPDI experimental test platform, the paper reports the results obtained using both diffusion controlled (HPDI) combustion strategy as well as the proposed partially-premixed combustion strategy (DI2).
2016-04-05
Technical Paper
2016-01-0978
Nolan Wright, Dustin Osborne, Nathan Music
Exhaust emissions of non-methane hydrocarbon (NMHC) and methane were measured from a Tier 3 dual-fuel demonstration locomotive running diesel-natural gas blend. Measurements were performed with the typical flame ionization detector (FID) method in accordance with EPA CFR Title 40 Part 1065 and with an alternative Fourier-Transform Infrared (FTIR) Spectroscopy method. Measurements were performed with and without oxidation catalyst exhaust aftertreatment. FTIR may have potential for improved accuracy over the FID when NMHC is dominated by light hydrocarbons. In the dual fuel tests, the FTIR measurement was 1-4% higher than the FID measurement of. NMHC results between the two methods differed considerably, in some cases reporting concentrations as much as four times those of the FID. However, in comparing these data it is important to note that the FTIR method has several advantages over the FID method, so the differences do not necessarily represent error in the FTIR.
2016-04-05
Technical Paper
2016-01-0616
Jayant Sarlashkar, Sankar Rengarajan, Ryan Roecker
Southwest Research Institute (SwRI) has successfully demonstrated the cooled EGR concept via the High Efficiency Dilute Gasoline Engine (HEDGE) consortium. Dilution of intake charge provides three significant benefits – (1) Better Cycle Efficiency (2) Knock Resistance and (3) Lower NOx/PM Emissions. But EGR dilution also poses challenges in terms of combustion stability, condensation and power density. The Dedicated EGR (D-EGR) concept brings back some of the stability lost due to EGR dilution by introducing reformates such as CO and H2 into the intake charge. Control of air, EGR, fuel, and ignition remains a significant challenge to realizing the aforementioned benefits without sacrificing performance and drivability. This paper addresses the DEGR solution from a controls standpoint. SwRI has been developing a unified framework for controlling a generic combustion engine (gasoline, diesel, dual-fuel natural gas etc.).
2016-04-05
Technical Paper
2016-01-0600
Zainal Abidin, Kevin Hoag, Douglas Mckee, Nicholas Badain
The engine intake process governs many aspects of the flow within the cylinder. The inlet valve is the minimum area so gas velocities at the valve are the highest velocity. Geometrical configuration of the inlet ports and the valves and the opening schedule create organized motions in the cylinder known as swirl and tumble. Good charge motion within the cylinder will produce high turbulence level at the end of compression stroke. As the turbulence resulting from the conversion energy of the inlet jet decays fast, the strategy is to encapsulate some of the inlet jet in the organized motions. In this work the baseline port of a 2.0 L gasoline engine was modified by inserting a tumble plate. The analysis was conducted using a 3-D CFD tool. The plate entrance was designed to minimize the pressure loss in the intake system. The tumble ratio increased by 35.9% at the intake valve closing.
2016-04-05
Technical Paper
2016-01-0595
Zainal Abidin, Radu Florea, Timothy Callahan
The current boom in natural gas from shale formations in the United States has reduced the price of natural gas to less than one-half the price of petroleum fuels. Thus it is attractive to convert high horsepower diesel engines that use large quantities of fuel to dual fuel operation where a portion of the diesel fuel is replaced by natural gas. The substitution is limited by emissions of unburned natural gas and severe combustion phenomena such as auto-ignition or knock of the mixture and high rates of pressure rise during the ignition and early phase combustion of the diesel and natural gas-air mixture. In this work, the knocking process for dual fuel combustion was investigated using 3-D CFD tool. Discrete phase model was used to simulate the injected diesel liquid into the chamber. The combustion process was modeled using the first principle of the detailed chemistry process.
2016-04-05
Technical Paper
2016-01-0834
Arjun Prakash, Roger Cracknell, Vinod Natarajan, David Doyle, Aaron Jones, Matthew Hinojosa, Peter Lobato
Octane appetite of modern engines has changed as engine designs have evolved to meet performance, emissions, fuel economy and other demands. The octane appetite of seven modern vehicles was studied in accordance with the octane index equation OI=RON-KS, where K is an operating condition specific constant, and S is the fuel sensitivity (RON-MON). Engines with a displacement of 2.0L and below and different combinations of boosting, fuel injection, and compression ratios were tested using a decorrelated RON-MON matrix of eight fuels. Power and acceleration performance was used to determine the K values for corresponding operating points. Previous studies have shown that vehicles manufactured up to 20 years ago mostly exhibited negative K values and the fuels with higher RON and higher sensitivity tended to perform better.
2016-04-05
Technical Paper
2016-01-0952
Gordon J. Bartley, Zachary Tonzetich, Ryan Hartley
A recent collaborative research project between Southwest Research Institute and the University of Texas at San Antonio has demonstrated that a ruthenium catalyst is capable of converting NOx emissions to N2 with high activity and selectivity. The catalyst can be used in the EGR leg of a D-EGR engine, where it uses CO and H2 present in the rich gas environment to reduce NOx to N2 with 100% efficiency close to 100% selectivity to N2. The NOx-free EGR gases can then be fed into the intake air without concerns that the NOx will lead to pre-ignition under high engine efficiency operating conditions.
2016-04-05
Journal Article
2016-01-0712
Terrence Alger, Mark Walls, Christopher Chadwell, Shinhyuk Joo, Bradley Denton, Kelsi Kleinow, Dennis Robertson
Experiments were performed on a small displacement (< 2 L), high compression ratio, 4 cylinder, MPI gasoline engine equipped with Dedicated EGR (D-EGR) technology using fuels with varying anti-knock indices. Gasolines with anti-knock indexes of 81, 89 and 93 AKI were tested. The engine was operated at a nearly constant EGR rate (~ 25%) and the overfuelling rate of the dedicated cylinder was swept between no overfuelling (Dϕ = 1.0 - equivalent to 25% LPL EGR) and the maximum allowable overfuelling based on the stability of the dedicated cylinder (Dϕ ~ 1.4-1.5 - e.g 40-50% overfuelling). The engine was run at knock-limited spark advance or MBT timing at a constant torque condition to demonstrate the impact of the overfuelling rate on combustion phasing and thus knock resistance of the engine. The resulting data were then compared across fuels to determine the tradeoff between the overfuelling rate required to achieve a certain knock resistance and the fuel octane rating.
2016-04-05
Journal Article
2016-01-0713
Terrence Alger, Raphael Gukelberger, Jess Gingrich
A series of tests were performed on a gasoline powered engine with a Dedicated EGR system. The results showed that changes in engine performance, including improvements in burn rates and stability, reductions in unburned hydrocarbons and increases in the oxides of nitrogen could not be adequately accounted for solely due to the presence of reformate in the EGR stream. In an effort to adequately characterize the engine's behavior, a new parameter was calculated, the Total Inert Dilution Ratio (TIDR), that accounts for the changes in the EGR quality as inert gases are replaced by reactive species such as CO and H2.
2016-04-05
Technical Paper
2016-01-1006
Cary Henry, Svitlana Kroll, Vinay Premnath, Ian smith, Peter Morgan, Imad Khalek
Recent legislation has been enacted requiring unprecedented reductions in greenhouse gas emissions, and thus improved fuel efficiency, from internal combustion engines. For light duty automotive applications, this mandated reduction in greenhouse gas emissions directly coincides with a required 80% reduction in gaseous criteria pollutant emissions, and a 90% reduction in particulate emissions. The dedicated EGR combustion strategy, developed by Southwest Research Institute, has been shown to provide reductions in fuel economy of up to 15% when compared with conventional non-EGR type strategies [1,2]. In addition to these observed improvements in fuel consumption, the use of cooled EGR has been shown to reduce certain criteria pollutants, including PM and PN emissions [2,3]. In this study, the criteria pollutant emissions from a D-EGR light duty vehicle were compared with emissions from an identical production GDI vehicle without externally cooled EGR.
2016-04-05
Technical Paper
2016-01-0067
Ryan Wilson, Wayne Music, Brian Anderson
Modern vehicular systems rely on millions of lines of code that must occasionally be updated to ensure safe and secure operations. Of the various techniques that could be used to update software or firmware on mobile platforms, cellular communications has a massive coverage footprint that ranges from urban to rural locations worldwide. Long Term Evolution (LTE) communications is becoming and will be the standard for global cellular communications for the foreseeable future. Personal cellular base stations such as femtocells, which play a key role in planned LTE coverage, have been shown to be vulnerable to compromise. Updates accomplished through a compromised base station could lead to an update that is compromised.
2015-09-29
Journal Article
2015-01-2775
Nicholas Badain, Thomas Reinhart, Coralie Cooper, James MacIsaac, John Whitefoot
This paper presents the fuel consumption results of engine and vehicle simulation modeling for a wide variety of individual technologies and technology packages applied to a long haul heavy duty vehicle. Based on the simulation modeling, up to 11% in fuel savings is possible using commercially available and emerging technologies applied to a 15L DD15 engine alone. The predicted fuel savings are up to 17% in a Kenworth T700 tractor-trailer unit equipped with a range of vehicle technologies, but using the baseline DD15 diesel engine. A combination of the most aggressive engine and vehicle technologies can provide savings of up to 29%, averaged over a range of drive cycles. Over 30% fuel savings were found with the most aggressive combination on a simulated long haul duty cycle. Note that not all of these technologies may prove to be cost-effective. The fuel savings benefits for individual technologies vary widely depending on the drive cycles and payload.
2015-09-29
Journal Article
2015-01-2769
Coralie Cooper, Thomas Reinhart, James David MacIsaac, John Whitefoot
This paper presents the results of engine and vehicle simulation modeling for a wide variety of individual technologies and technology packages applied to two medium-duty vocational vehicles. Simulation modeling was first conducted on one diesel and two gasoline medium-duty engines. Engine technologies were then applied to the baseline engines. The resulting fuel consumption maps were run over a range of vehicle duty cycles and payloads in the vehicle simulation model. Results were reported for both individual engine technologies and combinations or packages of technologies. Two vehicles, a Kenworth T270 box delivery truck and a Ford F-650 tow truck were evaluated. Once the baseline vehicle models were developed, vehicle technologies were added. As with the medium-duty engines, vehicle simulation results were reported for both individual technologies and for combinations. Vehicle technologies were evaluated only with the baseline 2019 diesel medium-duty engine.
2015-09-29
Journal Article
2015-01-2778
Joe Steiber, Coralie Cooper, John Whitefoot, James MacIsaac
Medium- and Heavy Duty Truck fuel consumption and the resulting greenhouse gas (GHG) emissions are significant contributors to overall U.S. GHG emissions. Forecasts of medium- and heavy-duty vehicle activity and fuel use predict increased use of freight transport will result in greatly increased GHG emissions in the coming decades. As a result, the National Highway Traffic Administration (NHTSA) and the United States Environmental Protection Agency (EPA) finalized a regulation requiring reductions in medium and heavy truck fuel consumption and GHGs beginning in 2014. The agencies are now proposing new regulations that will extend into the next decade, requiring additional fuel consumption and GHG emissions reductions. To support the development of future regulations, a research project was sponsored by NHTSA to look at technologies that could be used for compliance with future regulations.
2015-09-01
Technical Paper
2015-01-2045
Haiying Tang, Saad Abouzahr, Jeff Betz, Donald Breece, Jerry C. Wang, Kaustav Sinha, Scott O. Lindholm, Jeffery H. Hsu, Karin E. Haumann, Sidney Clark, Tracey King, Wayne E. Petersen
With the impending development of GF-6, the newest generation of engine oil, a new standardized oil oxidation and piston deposit test was developed using Chrysler 3.6 L Pentastar engine. The performance requirements and approval for passenger car light duty gasoline engine oil categories are set by the International Lubricants Standardization and Approval committee (ILSAC) and the American Petroleum Institute (API) using standardized testing protocols developed under the guidance of ASTM, the American Society for Testing and Materials. This paper describes the development of a new ASTM Chrysler oxidation and deposit test that will be used to evaluate lubricants performance for oil thickening and viscosity increase, and piston deposits.
2015-09-01
Technical Paper
2015-01-1968
Raphael Gukelberger, Gordon J. Bartley, Jess Gingrich, Terrence Alger, Steven Almaraz, Janet Buckingham, Cary Henry
Dedicated Exhaust Gas Recirculation (D-EGR®) technology provides a novel means for fuel efficiency improvement through efficient, on-board generation of H2 and CO reformate [1, 2]. In the simplest form of the D-EGR configuration, reformate is produced in-cylinder through rich combustion of the gasoline-air charge mixture. It is also possible to produce more H2 by means of a Water Gas Shift (WGS) catalyst, thereby resulting in further combustion improvements and overall fuel consumption reduction. In industrial applications, the WGS reaction has been used successfully for many years. Previous engine applications of this technology, however, have only proven successful to a limited degree. The motivation for this work was to develop and optimize a WGS catalyst which can be employed to a D-EGR configuration of an internal combustion engine. This study consists of two parts.
2015-07-29
Article
SAKOR Technologies supplies a test system for the Dream Chaser atmospheric flight control system, serving as a spacecraft emulator to test overall system performance.
2015-07-13
Article
Mark Brooks of Southwest Research Institute’s Automation and Data Systems Division discusses the latest issues and technologies related to cybersecurity for commercial vehicles.
2015-04-14
Technical Paper
2015-01-0743
Michael Clifford Kocsis, Shinhyuk Joo, Thomas Briggs, Terrence Alger
Abstract In response to the sensitivity to diesel aftertreatment costs in the medium duty market, a John Deere 4045 was converted to burn gasoline with high levels of EGR. This presented some unique challenges not seen in light duty gasoline engines as the flat head and diesel adapted ports do not provide optimum in-cylinder turbulence. As the bore size increases, there is more opportunity for knock or incomplete combustion to occur. Also, the high dilution used to reduce knock slows the burn rates. In order to speed up the burn rates, various levels of swirl were investigated. A four valve head with different levels of port masking showed that increasing the swirl ratio decreased the combustion duration, but ultimately ran into high pumping work required to generate the desired swirl. A two valve head was used to overcome the breathing issue seen in the four valve head with port masking.
2015-04-14
Technical Paper
2015-01-1062
E. Robert Fanick, Svitlana Kroll, Stefan Simescu
Abstract Semi-volatile organic compounds (SVOC) are a group of compounds that may form during combustion and/or are present in the unburned portion of the fuel and lubricating oil which ultimately become part of the exhaust. Many of these compounds are considered toxic or carcinogenic. Since these compounds are present in very low concentrations in diesel engine exhaust, the methods for sampling, handling, and analyzing these compounds are critical to obtaining representative and repeatable results. Engine testing is typically performed using a dilution tunnel. With a dilution tunnel, the collection of a representative sample is important. Experiments were performed with a modified EPA Method TO-9A to determine the equilibration time and other sampling parameters required for the measurement of SVOC in dilute exhaust. The results show that representative results can be obtained with this method.
2015-04-14
Journal Article
2015-01-1077
Huzeifa Badshah, Imad A. Khalek
Abstract Human exposure to vehicle exhaust during engine start-up can be encountered on a daily basis in parking lots, home garages, and vehicle stop/star traffic environment. This work is the first pilot study to characterize solid particle number and size distribution during engine start-up using various light-duty vehicles with different technology engines. A total of 84 vehicles were tested in this pilot study, consisting of post-2007 diesel engines equipped with high efficiency diesel particulate filters (DPFs) as well as modern gasoline port fuel injected (PFI) and gasoline direct injected (GDI) engines equipped with three-way-catalysts (TWCs). Particle concentration from DPF equipped diesel engines were found to be the lowest, while GDI and 8-cylinder PFI engines had the highest particle emissions.
2015-04-14
Technical Paper
2015-01-0778
Zainal Abidin, Christopher Chadwell
Abstract The presented work describes how spark calorimeter testing was used for parametric study and secondary circuit model calibration. Tests were conducted at different pressures, sparkplug gaps and supplied primary energies. The conversion efficiency increases and the spark duration decreases when the gas pressure or the sparkplug gap size is increased. Both gas pressure and sparkplug gas size increase the positive column voltage which represents part of the electrical energy delivered to the gas. The opposite direction occurs when the supplied primary energy is increased. The testing results were then used to calibrate the secondary circuit model which consisted of the sparkplug, the sparkplug gap and the secondary wiring. A step-by-step method was used to calibrate the three constants of the model to match the calculated delivered energy with test data during arc / glow phase.
2015-04-14
Technical Paper
2015-01-0203
Brian Anderson, Mark Brooks, Ryan Wilson, Purser K. Sturgeon II
Several wireless systems such as Dedicated Short Range Communication (DSRC), cellular, Wi-Fi, Bluetooth, and the Tire Pressure Monitoring System (TPMS) can be found on modern vehicles. In the future, Software Defined Radio (SDR) technology could be integrated into automobiles to increase the efficiency and adaptability of wireless communications systems. SDR is also a powerful tool for designing and testing new communications protocols. However there are also some security considerations associated with SDR. This paper will review some advantages of using SDR technology in the automotive domain as well as potential security issues. The authors are currently conducting research into the use of SDR technology to model wireless systems and investigate security threats in modern vehicular systems.
2015-04-14
Journal Article
2015-01-0781
Raphael Gukelberger, Jess Gingrich, Terrence Alger, Steven Almaraz
Abstract The ongoing pursuit of improved engine efficiency and emissions is driving gasoline low-pressure loop EGR systems into production around the globe. The Dedicated EGR (D-EGR®) engine was developed to minimize some of the challenges of cooled EGR while maintaining its advantages. The D-EGR engine is a high efficiency, low emissions internal combustion engine for automotive and off-highway applications. The core of the engine development focused on a unique concept that combines the efficiency improvements associated with recirculated exhaust gas and the efficiency improvements associated with fuel reformation. To outline the differences of the new engine concept with a conventional LPL EGR setup, a turbocharged 2.0 L PFI engine was modified to operate in both modes. The second part of the cooled EGR engine concept comparison investigates efficiency, knock resistance, combustion stability, and maximum load potential at high load conditions.
2015-04-14
Journal Article
2015-01-0783
Raphael Gukelberger, Jess Gingrich, Terrence Alger, Steven Almaraz, Bradley Denton
Abstract The ongoing pursuit of improved engine efficiency and emissions are driving gasoline low-pressure loop EGR systems into production around the globe. To minimize inevitable downsides of cooled EGR while maintaining its advantages, the Dedicated EGR (D-EGR®) engine was developed. The core of the D-EGR engine development focused on a unique concept that combines the efficiency improvements associated with recirculated exhaust gas and the efficiency improvements associated with fuel reformation. To outline the differences of the new engine concept with a conventional low-pressure loop (LPL) EGR setup, a turbocharged 2.0 L PFI engine was modified to operate in both modes and also compared to the baseline. The first part of the cooled EGR engine concept comparison investigates efficiency, emissions, combustion stability, and robustness at throttled part load conditions.
Viewing 1 to 30 of 552

Filter

  • Range:
    to:
  • Year: