Refine Your Search

Topic

Author

Affiliation

Search Results

Book

Hydrogen, The Post-Oil Fuel?

2012-11-01
Hydrogen, energy vector for the future? Or, on the contrary, limited to its current applications in the field of chemistry and refining for decades to come, possibly even until the end of the century? There is much controversy over this issue and two sides to the argument. Advocates of the hydrogen civilization consider that, following a technological revolution hydrogen will play a universal role alongside electricity as a substitute for fossil fuels, especially (but not only) in transport, leading to radical elimination of CO2 emissions. For the skeptics, and even outspoken opponents, hydrogen will remain restricted to its current applications due to the insoluble problems inherent to its generalized use, especially in transport. This book highlights the increasing and inevitable role of "energy" hydrogen – as opposed to chemical hydrogen – in the key sectors of transport and "clean" electricity production.
Book

Everything Works Wonderfully

2014-07-01
EVERYTHING WORKS WONDERFULLY is a 250-page A4 softback book written to provide a structured source of guidance and reference information on Servitization and the management of physical assets for people at all levels in industry: • Senior executives considering the expansion of their businesses into the provision of Asset Management services for the products they design and manufacture; • Middle management wishing to know what needs to be done to look after the assets they are responsible for and who to approach for help; • ‘Hands-on’ engineers looking for contacts and advice on detailed tools and techniques. • Academics may also find the book useful as a source of contacts and ideas for research.
Technical Paper

Performance and Emissions of an LPG Lean-Burn Engine for Heavy Duty Vehicles

1999-05-03
1999-01-1513
Performance and emissions of an LPG lean burn engine for heavy duty vehicles were measured. The piston cavity, swirl ratio, propane - butane fuel ratio, and EGR were varied to investigate their effects on combustion, and thus engine performance. Three piston cavities were tested: a circular flat-bottomed cavity with sloped walls (called the “bathtub” cavity), a round bottomed cavity (called the “dog dish” cavity), and a special high-turbulence cavity (called the “nebula” cavity). Compared to the bathtub and dog dish cavities, the nebula type cavity showed the best performance in terms of cyclic variation and combustion duration. It was capable of maintaining leaner combustion, thus resulting in the lowest NOx emissions. High swirl improved combustion by achieving a high thermal efficiency and low NOx emissions. In general, as the propane composition increased, cyclic variation fell, NOx emissions increased, and thermal efficiency was improved.
Technical Paper

Emissions from Buses with DDC 6V92 Engines Using Synthetic Diesel Fuel

1999-05-03
1999-01-1512
Synthetic diesel fuel can be made from a variety of feedstocks, including coal, natural gas and biomass. Synthetic diesel fuels can have very low sulfur and aromatic content, and excellent autoignition characteristics. Moreover, synthetic diesel fuels may also be economically competitive with California diesel fuel if produced in large volumes. Previous engine laboratory and field tests using a heavy-duty chassis dynamometer indicate that synthetic diesel fuel made using the Fischer-Tropsch (F-T) catalytic conversion process is a promising alternative fuel because it can be used in unmodified diesel engines, and can reduce exhaust emissions substantially. The objective of this study was a preliminary assessment of the emissions from older model transit operated on Mossgas synthetic diesel fuel. The study compared emissions from transit buses operating on Federal no. 2 Diesel fuel, Mossgas synthetic diesel (MGSD), and a 50/50 blend of the two fuels.
Technical Paper

Transmission Oil Degradation Warning Systems and Computing in Agricultural Tractors

2000-06-19
2000-01-1873
This communication examines three strategies of predictive lubricant monitoring and replacement, used for farm tractors or similar vehicles. These strategies optimise the draining periodicity. They are the off-line follow-up, the sensors follow-up and the analytical model follow-up. The implementation of the suggested analytical model will be discussed, on the basis of field collected data (on a series of tractors, either customer's or on loan). Regular oil samples, and significant ones carried out at the end of the study, were taken and analysed in order to predict the evolution of the lubricant characteristics. Extensions to the experimental study were carried out at the end of this work. They are discussed in the paper (FZG gear scuffing, 4 ball wear and EP…).
Technical Paper

Influence of Fuel Aromatics Type on the Particulate Matter and NOx Emissions of a Heavy-Duty Diesel Engine

2000-06-19
2000-01-1856
The influence of fuel aromatics type on the particulate matter (PM) and NOx exhaust emissions of a heavy-duty, single-cylinder, DI diesel engine was investigated. Eight fuels were blended from conventional and oil sands crude oil sources to form five fuel pairs with similar densities but with different poly-aromatic (1.6 to 14.6%) or total aromatic (14.3 to 39.0%) levels. The engine was tuned to meet the U.S. EPA 1994 emission standards. An eight-mode, steady-state simulation of the U.S. EPA heavy-duty transient test procedure was followed. The experimental results show that there were no statistically significant differences in the PM and NOx emissions of the five fuel pairs after removing the fuel sulphur content effect on PM emissions. However, there was a definite trend towards higher NOx emissions as the fuel density, poly-aromatic and total aromatic levels of the test fuels increased.
Technical Paper

Heavy Duty Testing Cycles Development: A New Methodology

2000-06-19
2000-01-1860
Testing cycles for heavy-duty vehicles are an important topic for authorities, manufacturers, fleet owners, etc. in order to assess exhaust gas emissions and fuel consumption. A new methodology was developed to derive representative testing cycles from velocity versus time driving information. During the development, the work was focussed on city-buses, but the methodology can be applied to heavy-duty vehicles in general. The testing cycles are ‘distance-based’, meaning they impose goal speeds at each location. This implies that during acceleration phases, the accelerator-pedal - and gear lever in case of manual transmission - can be operated in a realistic way. The techniques for deriving this kind of testing cycle are proposed. Results of on-board emission and fuel consumption measurements employing these testing cycles are presented for two 19 tons, 160kW city buses, equipped with respectively a diesel and a CNG (stoechiometric) engine, and a 10 tons 112 kW diesel delivery truck.
Technical Paper

Investigation of Package Bearings to Improve Driveline Performance

2000-06-19
2000-01-1785
The tapered roller bearings employed in axle centers for the pinion support are critical components in determining the noise, fuel economy and reliability characteristics of the vehicle. They represent a relatively complex mechanical and tribological system, with special requirements from the stiffness, lubrication and heat transfer points of view. This paper brings a contribution to the investigation of the intricate dependency between design parameters, environmental factors and the resultant performance of a package bearing in an integral double cup configuration. Axial compactness, reduced weight, and superior rigidity are only few of the multiple advantages recommending this type of double row bearings for automotive driveline applications. Different aspects related to the tapered roller bearing setting are analyzed in a theoretical and experimental manner, also under the consideration of the manufacturing and assembly processes.
Technical Paper

New Quiescent Combustion System for Heavy–Duty Diesel Engines to Overcome Exhaust Emissions and Fuel Consumption Trade–Off

2000-06-19
2000-01-1811
In the next few years, the USA, EU, and Japan plan to introduce very stringent exhaust emissions regulations for heavy–duty diesel engines, in order to enhance the protection air quality. This builds upon the heavy–duty diesel engine exhaust emissions regulations already in effect. At the same time, improvement in fuel consumption of heavy–duty diesel engines will be very important for lowering vehicle operating costs, conserving fossil fuel resources, and reduction of CO2 (greenhouse gas) levels. This paper presents a detailed review of a quiescent combustion system for a heavy–duty diesel engine, which offers breakthrough performance in terms of the exhaust emissions – fuel consumption trade–off, compared with the more conventional swirl supported combustion system. This conclusion is supported by experimental results comparing quiescent and swirl supported versions of various combustion system configurations.
Technical Paper

Compressor Oil Carryover and Its Effect on the Pneumatic System

1999-11-15
1999-01-3768
Oil carryover is present in all pneumatic systems where the compressed air is generated by oil lubricated compressors. With the increased use of electronic and small orifice components on trucks and coaches, the problem of contamination and failure related to oil carryover in the compressed air system has increased. Even though the rate of oil carryover out of the compressor has improved over recent years, problems persist. This paper will describe how the oil is transported out of the compressor, the various states oil is generated including vapor pressure profiles and size distribution of the condensed aerosols. Also reviewed is the oil removal effectiveness of various components downstream of the compressor. A model of oil liquefaction from vapor and aerosol states will be presented. The effect of liquefied oil combined with other contaminates in the pneumatic system and various design criteria for downstream equipment will be discussed.
Technical Paper

Benefits of Profiling Tapered Roller Bearings - Matching Driveline Component Performance to the Demands of Higher Horsepower Engines of Heavy Duty Trucks

1999-11-15
1999-01-3767
The heavy-duty trucking industry is continuing to move toward the use of higher horsepower engines. Engines exceeding 450 horsepower have become increasingly popular, with 500 - 600 horsepower engines expected to share a significant portion of the truck engine market in the next decade {Reference 1}. Sometimes these higher horsepower engines are used with existing gross combined vehicle weight, simply to increase the speed at which payloads are delivered. However, when higher engine horsepower is used to transport increased payloads, the result is higher loads and stresses on all driveline components between the engine and the wheels. All components downstream of the engine could be adversely affected.
Technical Paper

Analysis of Elastic Distortions of a Piston Ring in the Reciprocating Air Brake Compressor Due to the Installation Stresses

1999-11-15
1999-01-3770
The objective of this paper is to present the results of an investigation of elastic distortions of split piston rings that are used in lubricated and non-lubricated air brake compressors. Concepts of advanced stress analysis and Finite Element Analysis (FEA) have been employed in this study. The analysis of elastic distortions (twist) of piston rings due to the installation stresses has been quite poorly documented in the technical literature. As a result, unjustifiable engineering assumptions are some time made which result in misleading design solutions. This paper demonstrates analytically and with the support of FEA the mechanical/geometrical parameters of a split ring which affect the twist of the ring during the installation in the cylinder bore, and the calculated magnitude of this twist along the ring circumference.
Technical Paper

Analytical Solution of Piston Ring Pack Lubrication for Truck Air Brake Compressor

1999-11-15
1999-01-3769
This paper presents an analytical solution of piston ring pack lubrication for two-cylinder truck air brake compressor. A system of nonlinear equations with seven variables was developed to describe lubrication phenomena of the piston ring pack for both fully flooded and starvation conditions. The full mass conservation boundary conditions defined by JFO ([14],[15]) theory were employed for complete description of the cavitation algorithm with enclosed and open cavitation patterns. Impact of the piston ring design parameters such as offset, crown height, and tension on the oil transport, lubrication conditions and friction losses of the compressor were discussed in details.
Technical Paper

A Three Year Comparison of Natural Gas and Diesel Transit Buses

1999-11-15
1999-01-3738
This report details the experiences of two California public transit agencies that replaced aging diesel buses with new compressed natural gas (CNG) buses in 1994. The operating characteristics and costs of 170 natural gas buses are compared with 73 older diesel buses. The natural gas bus fleets have operated well and led to cost reductions in both fleets. The findings are particularly significant because both Sacramento Regional Transit District (RT) and SunLine Transit Agency have been using the same engine-chassis configuration, thus enabling a valid method to combine cost data for a large sample fleet of buses. The data indicate that labor for diesel equipment was almost twice that for CNG vehicles, parts were 25% more and fuel costs were nearly double. In 1997, CNG buses saved RT over $1 million in fuel, maintenance, parts and hazardous waste disposal, a 38% per mile reduction over the cost of their older diesel buses.
Technical Paper

Leveraging a Commercial Medium-Duty Product for the Heavy-Duty Pickup Truck Market

1999-11-15
1999-01-3743
Allison Transmission has developed a family of three new automatic transmission products, the 1000, 2000 and 2400 Series™, for the light and medium-duty commercial markets. This technical paper will discuss how Allison first identified the opportunity, established the market requirements, designed, and validated these new products.
Technical Paper

The New Allison HD4070 Transmission - Design, Development and Applications

1999-11-15
1999-01-3742
Allison Transmission has been a key player in the Military and Heavy Duty Commercial truck markets for many years. These tough vocations require transmissions that are not only capable of heavy loads, rigorous duty cycles, and proven reliability, but also provide value for the end-user and maintain compatibility with leading edge technological improvements of engines and other parts of the vehicle system. The Allison HD4070 transmission is one of the latest transmission offerings from Allison Transmission to meet the “next generation” heavy-duty vehicle needs. This product increases value to the vehicle manufacturer and customer, and provides compatibility with the fast changing electronics capabilities of modern vehicle systems and engines. These improvements are offered in a durable design that has been the trademark of Allison transmissions in these markets.
Technical Paper

Vocational and Body Builder Controls Features of the Allison 1000/2000/2400 Series™ Automatic Transmission

1999-11-15
1999-01-3744
Light and Medium Duty Trucks (N.A. Classes 2–7) make up of a wide variety of vehicle configurations. These vehicles, in addition to providing the basic hauling needs of the industry, also provide distinct operational features dictated by the vocation they serve. This results in additional auxiliary equipment and control features being employed. The control system for Allison Transmission's new 1000/2000/2400 Series™ transmission was designed to satisfy the many requirements of this complex market. This paper will describe these features and how they interact with various control aspects of the vehicle. Also, future control features will be discussed.
Technical Paper

Design of a Multilink Independent Front Suspension for Class A Motor Homes

1999-11-15
1999-01-3731
Motorized recreational vehicles with front axle load ratings that exceed 4,086 kilograms, or 9,000 pounds, are traditionally equipped with rigid I-beam type axles. These axles are used in this application because of their ability to carry high axle loads at a reasonable cost, and their durability history in truck usage. Recently, several manufacturers have used independent type front suspension designs. A multi-link type suspension offers some unique solutions in optimizing the front suspension design. This paper describes the performance goals (i.e. Suspension Design Factors) and tradeoffs in pursuit of the final design. Establishing these SDF’s, achieving them and their relationship to vehicle performance are the focus of this paper. Plots of the kinematic and elastic characteristics are included to illustrate some of the unique features of this multi-link suspension.
Technical Paper

Optimal Mass and Geometric Parameters in Multi-Wheel Drive Trucks for Improved Transport and Fuel Efficiency

1999-11-15
1999-01-3733
To develop better performing vehicles, for ground transportation, it is necessary to improve the theory in vehicle dynamics for choosing suitable mass and geometric parameters for highway as well as for off road trucks. A new approach is required for choosing such optimal mass and geometric parameters. The present paper is devoted to this problem. A new method for synthesis of mass and geometric parameters is introduced here. The method allows us to synthesize the parameters in such way as to provide a vehicle with the best transport efficiency under various road surface conditions. Constraints such as limitations on these parameters, vehicle running modes, mass and geometric parameters are included in the model. Furthermore other constraints for vehicle running abilities which are dependent on mass and geometric parameters, as well as an algorithm for synthesizing mass and geometric parameters are also included in the paper for pre-optimization process.
X