Criteria

Text:
Affiliation:
Display:

Results

Viewing 1 to 27 of 27
2013-09-24
Journal Article
2013-01-2422
Yu Zhang, Ilya Sagalovich, William De Ojeda, Andrew Ickes, Thomas Wallner, David D. Wickman
Low temperature combustion through in-cylinder blending of fuels with different reactivity offers the potential to improve engine efficiency while yielding low engine-out NOx and soot emissions. A Navistar MaxxForce 13 heavy-duty compression ignition engine was modified to run with two separate fuel systems, aiming to utilize fuel reactivity to demonstrate a technical path towards high engine efficiency. The dual-fuel engine has a geometric compression ratio of 14 and uses sequential, multi-port-injection of a low reactivity fuel in combination with in-cylinder direct injection of diesel. Through control of in-cylinder charge reactivity and reactivity stratification, the engine combustion process can be tailored towards high efficiency and low engine-out emissions. Engine testing was conducted at 1200 rpm over a load sweep.
2010-10-05
Technical Paper
2010-01-1914
Mahender Singh
This paper talks about using an approach to simulate snow mass falling from roof of cab on the cowl tray of a commercial truck and predicting the durability life of the cowl tray based on this loading. It has always been a challenge for analysts to model the behavior of snow/slurry in dynamic simulations especially where the area of concern is structure and not the fluid. The conventional approach followed in most industries would be either to model snow as soft rubber or to divert from the conventional Lagrangian algorithm for mesh movement towards Eulerian method (or ALE algorithm). Although modeling snow as soft rubber captures the basic physics of the problem, it is not able to correctly simulate the fluid structure interaction behavior and the pressure wave movement inside the snow/slurry when it comes in contact with the structure.
2012-09-24
Technical Paper
2012-01-1972
Xiaoye Han, Kelvin Xie, Ming Zheng, William De Ojeda
The use of gasoline fuels in compression ignition engines, with or without diesel pilots, has shown encouraging progress in engine efficiency and emissions. The dual fuel combustion of gasoline-diesel offers the flexibility of modulating the cylinder charge reactivity, but an accurate and reliable control over the ignition in the dual fuel applications is more challenging than in classical engines. In this work, the gasoline-diesel dual fuel operation is investigated on a single cylinder research engine. The effects of the intake boost, exhaust gas recirculation (EGR) rates, diesel/gasoline ratio, and diesel injection timing are studied in regard to the ignition control. The results indicate that at low load, a diesel pilot can improve the cylinder charge reactivity and reduce emissions of incomplete combustion products.
2012-09-24
Journal Article
2012-01-1979
Shinhyuk Michael Joo, Terrence Alger, Christopher Chadwell, William De Ojeda, Jacob Zuehl, Raphael Gukelberger
A 13 L HD diesel engine was converted to run as a flame propagation engine using the HEDGE™ Dual-Fuel concept. This concept consists of pre-mixed gasoline ignited by a small amount of diesel fuel - i.e., a diesel micropilot. Due to the large bore size and relatively high compression ratio for a pre-mixed combustion engine, high levels of cooled EGR were used to suppress knock and reduce the engine-out emissions of the oxides of nitrogen and particulates. Previous work had indicated that the boosting of high dilution engines challenges most modern turbocharging systems, so phase I of the project consisted of extensive simulation efforts to identify an EGR configuration that would allow for high levels of EGR flow along the lug curve while minimizing pumping losses and combustion instabilities from excessive backpressure. A potential solution that provided adequate BTE potential was consisted of dual loop EGR systems to simultaneously flow high pressure and low pressure loop EGR.
2012-09-24
Journal Article
2012-01-1976
William De Ojeda, M. Rajkumar
Diesel engine manufacturers have faced stringent emission regulations for oxides of nitrogen and particulate emissions for the last two decades. The emission challenges have been met with a host of technologies such as turbocharging, exhaust gas recirculation, high- pressure common rail fuel injection systems, diesel aftertreatment devices, and electronic engine controls. The next challenge for diesel engine manufacturers is fuel-economy regulations starting in 2014. As a prelude to this effort the department of energy (DOE) has funded the Supertruck project which intends to demonstrate 50% brake-thermal efficiency on the dynamometer while meeting US 2010 emission norms. In order to simultaneously meet the emission and engine efficiency goals in the cost effective manner engine manufacturer have adopted a systems approach, since individual fuel saving technologies can actually work against each other if fuel economy is not approached from a total vehicle perspective.
2008-08-04
Article
Navistar signed a joint-venture agreement with Mahindra & Mahindra to produce diesel engines for medium and heavy commercial trucks and buses in India. The joint venture, to be named Mahindra International Engines, will be 51% owned by Mahindra & Mahindra and 49% owned by Navistar.
2012-08-13
Article
Navistar is providing the executive leadership for this year’s SAE Commercial Vehicle Engineering Congress, taking place in Rosemont, IL, on Oct. 2-3. Ramin Younessi, Group Vice President, Product Development, Navistar Inc., discusses how the Congress is shaping up and the company’s future product plans incorporating the next-gen ICT+ (in-cylinder technology plus) system, which adds urea-based aftertreatment to its EGR technology.
2012-10-01
Article
Navistar International Corp. and Chinese truck maker Anhui Jianghuai Automobile Co. Ltd. (JAC) recently received formal approval from China’s National Development and Reform Commission (NDRC) to move forward with their commercial-engine joint venture, first announced in September 2010 when the companies signed an agreement.
2012-10-09
Article
New commercial vehicles, onboard storage tanks, and shipping container-sized fueling stations signal the latest CNG products.
2009-12-03
Article
One of Navistar International Corp.’s wholly owned affiliates has signed a joint venture agreement with U.K.-based Modec Ltd. to create the Navistar-Modec EV Alliance, LLC. The JV will produce and market Class 2c-3 all-electric commercial trucks for sale in North, Central, and South America.
2017-03-14
Article
International Truck recently unveiled its all-new engine for the Class 8 market called the International A26, in addition to a new initiative called Project Alpha, which brought together a small team of powertrain engineers dedicated to a new perspective on engine development.
2009-04-07
Article
Caterpillar and Navistar International Corp. have formed a strategic alliance to produce Cat heavy-duty vocational trucks for North America. Cat and Navistar have already started the co-development of the new line of trucks, which will be manufactured in Navistar's Garland, TX facility and be sold and serviced through the Cat North American Dealer network.
2010-01-14
Article
The U.S. Department of Energy recently awarded $187 million for nine projects aimed at improving vehicle efficiency. Most of the grant money, $115 million, is targeted at advances that will increase the fuel efficiency of Class 8 long-haul freight trucks 50% by 2015. Among the technologies to be investigated are engine combustion, engine waste heat recovery, powertrain hybridization, idle reduction, and aerodynamics.
2010-03-01
Article
Navistar Inc. and Clean Air Power Ltd. have entered into a concept development agreement to enable Navistar’s MaxxForce 13 big-bore engine to run on natural gas and diesel fuel for the North American market.
2009-02-19
Article
The U.S. Army has awarded Navistar Defense nearly $79 million to provide 605 vehicles for Operation Iraqi Freedom. Under the new contract, which is in addition to the $2.3 billion in military contracts for 2009 announced on Jan. 5, Navistar will provide the Army with 328 fuel trucks and 277 water tankers—all customized from the WorkStar platform.
2016-01-11
Article
Navistar CIO Terry Kline talks about the company’s vehicle connectivity strategy and its new over-the-air reprogramming for improved uptime, which it claims is an industry-first technology for heavy trucks.
2016-08-16
Article
With its new-generation X Series modular diesel engines, Cummins promises new levels of fuel-efficiency and power, compliance with 2017 EPA greenhouse-gas emissions standards and sophisticated OTA capabilities.
2016-09-14
Article
Exa and Navistar researchers examine CFD simulations and wind-tunnel test results to increase the understanding of simulation methods used to reveal aerodynamic losses in the real-world environment.
2013-07-19
Article
Dana Holding Corp. has been named the standard and exclusive supplier of steer axles, drive axles, and driveshafts for Navistar's new International TerraStar 4x4 medium-duty truck. Dana’s Spicer Model 273 front drive steer axle has a turn angle of 42°, a GAWR (gross axle weight rating) of 8000 lb, and popular axle ratios.
2013-04-15
Article
The truck maker's Project Horizon concept showcases technology related to aerodynamics, lighting, and chassis that could be on the road within 24 to 36 months.
2017-04-03
Article
Commercial vehicles are at the forefront of the Internet of Things movement, leveraging the connectivity that many have deployed for years. Equipment manufacturers are using IoT connections to improve their manufacturing operations, upgrade diagnostics to prognostics and improve maintenance operations.
2015-09-29
Journal Article
2015-01-2777
Gary Salemme, Erik Dykes, Daniel Kieffer, Michael Howenstein, Matthew Hunkler, Manik Narula
Abstract Simulations used to estimate carbon dioxide (CO2) emissions and fuel consumption of medium- and heavy-duty vehicles over prescribed drive cycles often employ engine fuel maps consisting of engine measurements at numerous steady-state operating conditions. However, simulating the engine in this way has limitations as engine controls become more complex, particularly when attempting to use steady-state measurements to represent transient operation. This paper explores an alternative approach to vehicle simulation that uses a “cycle average” engine map rather than a steady state engine fuel map. The map contains engine CO2 values measured on an engine dynamometer on cycles derived from vehicle drive cycles for a range of generic vehicles. A similar cycle average mapping approach is developed for a powertrain (engine and transmission) in order to show the specific CO2 improvements due to powertrain optimization that would not be recognized in other approaches.
2014-09-30
Journal Article
2014-01-2314
John Stuart, Stefano Cassara, Brendan Chan, Nicholas Augustyniak
Wobble and shimmy vibrations are commonly observed in commercial highway vehicles with solid-beam front axles. These vibrations are typically self-excited and manifest themselves as sustained oscillations about the kingpin and axle tramp. A study was initiated to investigate and quantify wobble and shimmy behaviors, with a primary focus on wobble. A cross functional team including test and simulation engineers evaluated a vehicle exhibiting these behaviors. The team developed an ADAMS model to reproduce the behaviors and developed a DOE to quantify the impact of variables and combinations of variables. The evaluation demonstrated that dynamic imbalance in the rotating masses is a primary source of excitation. Wheel run-out, caster angle, tire brand, tire wear and tire inflation are also significant sources. Future studies will use these findings to mitigate the concern.
2013-09-24
Technical Paper
2013-01-2412
Kevin Golsch, Bradley Duncan, Satheesh Kandasamy
Recent regulations on greenhouse gas (GHG) emission standards for heavy duty vehicles have prompted government agencies to standardize procedures to assess aerodynamic performance of Class 8 tractor-trailers. The coastdown test procedure is the primary reference method to assess vehicle drag and other valid alternatives include wind tunnel testing and computational fluid dynamics (CFD) simulations. While there have been many published studies comparing results between simulations and wind tunnel testing, it is less well understood how to compare results with coastdown testing. Both the wind tunnel and simulation directly measure aerodynamic drag forces in controlled conditions, while coastdown testing is conducted in an open road environment, aerodynamic forces are calculated from a road load equation, and variable wind and vehicle speed introduce additional complexity.
2017-09-19
Article
The International Catalist SuperTruck employed lightweighting strategies to help improve efficiency, and Navistar's focus on weight reduction continues unabated for its SuperTruck II program.
2016-09-27
Technical Paper
2016-01-8140
Devaraj Dasarathan, Ashraf Farag, Matthew Ellis
Abstract Recent regulations on greenhouse gas (GHG) emission standards for heavy-duty vehicles have prompted government agencies to standardize procedures assessing the aerodynamic performance of Class 8 tractor-trailers. The coastdown test procedure is the primary reference method employed to assess vehicle drag currently, while other valid alternatives include constant speed testing, computational fluid dynamics (CFD) simulations, and wind tunnel testing. The main purpose of this paper is to compare CFD simulations with a corresponding 1/8th scale wind tunnel test. Additionally, this paper will highlight the impacts of wind tunnel testing on the total drag coefficient performance as compared to full scale open road analysis with and without real world, upstream turbulence wind conditions. All scale model testing and CFD simulations were performed on a class 8 tractor with a standard 53-foot dry-box trailer.
2017-11-13
Article
Navistar president and CEO Troy Clarke recently signaled an acceleration of new product offerings and integrations stemming from its partnership with Volkswagen Truck & Bus. Chief among these activities is to converge the two companies’ connectivity activities and to develop an electric-powered, medium-duty vehicle for the U.S. by late 2019 or early 2020.
Viewing 1 to 27 of 27

    Filter

    • Range:
      to:
    • Year: