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Technical Paper

“MBE 4000-A New Engine for the US Class 8 Truck Market”

2000-12-04
2000-01-3457
Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.
Technical Paper

pCBT: A New Material for High Performance Composites in Automotive Applications1

2004-10-26
2004-01-2698
Cyclic oligomers of butylene terephthalate (CBT™)† represent a new chemical route to semi-crystalline thermoplastic polybutylene terephthalate (PBT). The oligomers of interest melt completely at about 150°C to produce a low viscosity fluid that is ideal for wetting and dispersing fibrous fillers and reinforcements thereby enabling the development of composites that were previously not possible when working with high viscosity commercial PBT. Introduction of catalyst to undiluted molten cyclic oligomer leads to rapid ring opening polymerization and the formation of high molecular weight thermoplastic PBT without the generation of volatile organic compounds. The polymer resulting from this polymerization will be hereby referred to as pCBT. Treatment of cyclic oligomers in this fashion results in pCBT thermoplastic resin with a high melting point (230°C) and physical performance similar to that of other commercially available PBT resins.
Technical Paper

Zero Emission Vehicles

1994-04-01
941108
Recharging electric vehicles with photovoltaics (PV) results in a truer “zero-emission” vehicle. Other papers have discussed the complex issue of distributed tailpipe emissions versus displaced emissions from centralized generating stations. The use of PV to recharge electric vehicles avoids the distributed versus centralized emission controversy because PV has minimal environmental impact. Even when considering the total fuel cycle, including fuel extraction and plant construction, PV still retains a significant environmental advantage over conventional electrical generation technologies. This paper reviews total fuel cycle emissions and then addresses the use of PV to recharge electric vehicles. The data presented in this paper applies also to hybrid electric vehicles.
Technical Paper

Yield Mapping with Digital Aerial Color Infrared (CIR) Images

1999-09-14
1999-01-2847
Yield potential was predicted and mapped for three corn fields in Central Illinois, using digital aerial color infrared images. Three methods, namely statistical (regression) modeling, genetic algorithm optimization and artificial neural networks, were used for developing yield models. Two image resolutions of 3 and 6 m/pixel were used for modeling. All the models were trained using July 31 image and tested using images from July 2 and August 31, all from 1998. Among the three models, artificial neural networks gave best performance, with a prediction error less than 30%. The statistical model resulted in prediction errors in the range of 23 to 54%. The lower resolution images resulted in better prediction accuracy compared to resolutions higher than or equal to the yield resolution. Images after pollination resulted in better accuracy compared to images before pollination.
Technical Paper

World Fuels and Modern Fuel Systems - A Path to Coexistence

2015-09-29
2015-01-2818
All around the world, steps are being taken to improve the quality of our environment. Prominent among these are the definition, implementation, and attainment of increasingly stringent emissions regulations for all types of engines, including off-highway diesels. These rigorous regulations have driven use of technologies like after-treatment, advanced air systems, and advanced fuel systems. Fuel dispensed off-highway is routinely and significantly dirtier than fuel from on-highway outlets. Furthermore, fuels used in developing countries can be up to 30 times dirtier than the average fuels in North America. Poor fuel cleanliness, coupled with the higher pressures and performance demands of modern fuel systems, create life challenges greater than encountered with cleaner fuels. This can result in costly disruption of operations, loss of productivity, and customer dissatisfaction in the off-highway market.
Technical Paper

Wiremesh Mounting System for Low Temperature Diesel Catalytic Converters

2005-11-01
2005-01-3508
Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.
Technical Paper

Winterization Of Construction Equipment - Report of CIMTC Subcommittee XV—Winterization

1957-01-01
570031
SINCE 1954 the CIMTC Subcommittee has been engaged in a program to meet military requirements through industry's production of construction equipment which can give satisfactory cold weather performance down to temperatures of −65 F. Individual contracts for three crawler tractors and one motor grader were negotiated by ERDL for these projects, and their performance is discussed. Industry participation was subsequently expanded to include engineering tests in the cold weather conditions of the Mesabi Iron Range. This joint report of the Winterization Sub-committee of the CIMTC and ERDL Winterization Section consists of separate papers by various members and consultants of this Sub-committee and ERDL personnel.
Technical Paper

Wind-Averaged Drag Determination for Heavy-Duty Vehicles Using On-Road Constant-Speed Torque Tests

2016-09-27
2016-01-8153
To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.
Technical Paper

Wind Effects on Dynamic Stability of Tractor Trailers in Winter Conditions

2009-10-06
2009-01-2915
There is a limited amount of data in literature discussing dynamic instability of tractor trailers due to wind speed and wind gusts on slippery surfaces. This paper outlines an analytical approach to assess tractor trailer performance due to these factors. The paper considers short-period wind gusts as well as uplift effect of the wind, frictional properties of the roadway, vehicle speed, jackknife effects, inertial (both translational and rotational) properties of tractor trailer combinations. Correlation between parameters related to semi dynamic instabilities are offered in a graphical format.
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Wiley SAE MOBILUS® eBook Package

2018-03-23
Committed to being the primary source for aerospace and ground vehicle engineering resources, SAE International has added the full compilation of our Wiley eBook collections to the SAE MOBILUS® technical resource platform. Purchasable as an annual subscription and containing the titles from the Wiley Aerospace Collection, the Wiley Automotive Collection, the Wiley Computer Systems Collection, and the Wiley Cyber Security Collection.
SAE MOBILUS Subscription

Wiley Automotive Collection

2018-03-23
Purchasable as an annual subscription, the Wiley Automotive Collection contains 20 eBook titles and focuses on a wide range of categories, including engines, transmission, chassis, body, electrical, safety, and manufacturing. Titles covering new and emerging topics such as battery technology and electric and hybrid vehicles are included as well, making the series an essential addition to any institution’s automotive resources.
Technical Paper

Why Not 125 BMEP in an L-Head Truck Engine?

1939-01-01
390130
HIGH output per cubic inch of piston displacement is desirable not alone for the purpose of being able to transport more payload faster, but more particularly for the invariably associated byproduct of lower specific fuel consumption, and especially at road-load requirements. The only way of accomplishing this purpose is through the use of higher compression ratios, and the limiting factors for this objective are fuel distribution and the operating temperatures of the component parts. A manifold is proposed which not only definitely improves distribution at both full and road loads, but has the inherent additional advantage of reducing the formation of condensate, thus still further facilitating a reduction in road-load specific fuel consumption. Hydraulic valve lifters, obviation of mechanical and thermal distortion, and controlled water flow are the essentials in improved cooling.
Technical Paper

Whole Body Vibration Levels: A Realistic Baseline for Standards

1976-02-01
760415
Statistical measures of whole-body vibration from ambulation are shown to be higher than those from operation of earthmoving machinery and significantly higher than published guidelines for human exposure to whole-body vibration. The inconsistency of human response to low level vibration of technological origin as compared to human imperceptiveness to high level vibration from ambulation is discussed.
Technical Paper

When the Workplace Takes Its Toll: Combating Stress

1992-04-01
920905
The pressures created by the work environment and its demands can be many and varied. The effect of these pressures and demands can be extremely taxing to essentially every facet of the person experiencing them. However, this stress can be effectively managed and even prevented by using the appropriate measures.
Technical Paper

Wheel Traction Prediction - A Comparison Between Models and Experimental Data

2004-10-26
2004-01-2707
The paper attempts to determine which traction model best fits with experimental data for a romanian lugged tractor tire. Different models for predicting net traction and traction efficiency for off-road conditions were considered. These models assume different tire-ground pressure distributions (constant, parabolic) over the undertread area and different contact patch length calculations. Experiments were conducted and the results were compared to the theoretical data. Two of the models are the best fit with the experimental data; both models assumed a parabolic pressure distribution over the undertread.
Journal Article

Wheel Chock Key Design Elements and Geometrical Profile for Truck Vehicle Restraint

2018-06-06
Abstract Wheel chocks are rather simple compliant mechanisms for stabilizing vehicles at rest. However, chocks must be carefully designed given the complex interaction between the chock and the tire/suspension system. Despite their importance for safety, literature is surprisingly limited in terms of what makes a wheel chock efficient. Using simple but reliable quasi-static mechanical models, this study identifies mechanical requirements that help to avoid a number of failure modes associated with many existing wheel chocks. Given that chock grounding is not always possible, a chock’s maximum restraining capacity is only obtained when the wheel is completely supported by the chock. A generic chock profile is proposed to achieve this objective while mitigating undesirable failure modes. The profile is based on fundamental mechanical principles and no assumption is made on the load interaction between the chock and the wheel.
Technical Paper

What is This Thing Called A System (and How Can I Go About Understanding It?)

1989-11-01
892473
This paper describes how the needs of the truck end-user have changed under the pressures of deregulation and competition, and how the truck supply community has responded. It observes that traditional management and hardware responses are yielding diminishing improvements. Significant further improvement is postulated based on application of electronic technology to functional control of a “truck system”. This is defined as a technological discontinuity where a new perspective, “thinking systems” will be needed. The post-1995 truck system is described; and what “thinking systems” entails and “how to create a system” are discussed. It is further postulated that this change in technology will have major impacts on the structure of the truck manufacturing industry, and the capabilities required of its management and technical communities.
Technical Paper

What SPC Can Do for You

1986-09-01
861219
Quality improvement, widely accepted as the key to survival in today's global marketplace, can only be achieved through a disciplined approach to problem solving based on proven statistical process control (SPC) techniques. Improving quality also improves productivity, and SPC applications are generating substantial savings for both product and service organizations throughout industry.
Technical Paper

What Every Engineer Should Know About Finite Element Analysis Methods

1986-09-08
861294
The scope of Finite Element Analysis in the Product Development Cycle is given. A brief review of the development process is given. A brief description of the analysis method is presented. A description of how it works, how is it implemented, and where do I use it are included. The entire range of questions are answered through, how do I train for it, how do I manage it, along with what are the limitations and what are the benefits of this analysis method.
Technical Paper

Wet Clutch Energy Calculation

1984-09-01
841067
Formulas are derived to show that moving elements of a drive train can contribute to the energy seen by the clutch plates. Oscillograph traces, sample calculations and photographs of failed plates show actual energy at failure of test plates. The formula is presented for calculating instantaneous energy when coefficient of friction, apply pressure and slip speed are known or can be estimated.
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