Search Results

Fuel economy, Emission regulation and extended oil drain intervals (ODI) are the three key driving forces for engine oil development. More and more attentions have been focused on long ODI diesel engine oil both from the domestic OEMs and oil suppliers, and the ODI was being periodically improved from a normal mileage of about 1×104 kilometers to 6/8/10×104 km or even 12×104 km just within several years on China market. Lots and lots of factors may affect the oil life including oil properties, engine technologies, after-treatment devices and engine working conditions and so on. While from the oil side, the main factors contribute to the oil drain intervals may be the oil nitration and oxidation, soot contamination, base number deterioration and sludge accumulation and etc. There are two strategies to extend the oil longevity applied currently.

An inhibitor package which is silicate-, nitrate-, borate- and phosphate-free has been developed as the basis for a world-wide automotive coolant formulation. The formulation contains aliphatic mono- and dicarboxylic acids and tolyltriazole as the sole inhibitors. Formulations containing carboxylic acid inhibitors have been studied in ASTM bench tests and found to sufficiently protect all prevalent cooling system metals. In addition, fleet tests have shown that carboxylic acid inhibitors deplete much more slowly than conventional inhibitors, making possible a much longer life coolant. Results from laboratory tests which simulate extended usage indicated that carboxylic acid-containing coolants have a significantly longer life span for the protection of all cooling system metals. Finally, the carboxylic acid/tolyltriazole inhibitor package is completely adaptable to a propylene glycol base.

Recently various kinds of position sensors have been used in automotive subsystems which include Electronic Fuel Injection, Active Suspension and Exhaust Gas Recirculation (EGR). Because a potentiometer has a simple structure in which a brush slides on a resistor surface, it has many advantages such as high temperature applications, low cost, high signal level and almost infinite resolution compared to other kinds of position sensors that are magnetic or optical in nature. The potentiometer is considered to have the highest potential for a position sensor. However, conventional potentiometers sometimes lose their linearity after use under severe conditions such as engine vibration (dither). They can endure only tens of millions of cycles of dither.

This paper summarizes a technology roadmap for completing advanced development of a Proton Exchange Membrane (PEM) Regenerative Fuel Cell (RFC) to meet long life (20,000 hrs at 50% duty cycle) mobile or portable power system applications on the surface of the Moon and Mars. Development of two different sized RFC power system modules is included in this plan (3 and 7.5 kWe). A conservative approach was taken which includes the development of a Ground Engineering System (GES), Qualification Unit (QU), and Flight Unit (FU). Development of a long life system was estimated to require about 7 years (through flight qualification). This development plan was formulated as part of a NASA Lewis task order contract (NAS3-25808) entitled “Mars Power System Concept Definition.” This paper includes a concept description, technology assessment, development issues, development tasks, and development schedule.

This paper shows that the analysis of factors such as costs, weights, fuel distribution logistics, etc. indicates that the replacement of internal combustion engines (ICE) by fuel cell/electric motor (FC/EM) systems, can be more attractive to aeronautical than to automotive applications. For long range airplanes especially, where the fuel represents an important fraction of the vehicle weight, the penalties from that replacement by a heavier system, can be overcome by the fuel weight reductions resulting from the higher fuel cell efficiencies. The necessity of FC/EM powered airplanes is also discussed in view of the eventual climate effects the air traffic may have, due to the injection of carbon dioxide and water vapor into the high troposphere.

A study is made of U.S. and worldwide aluminum supply/demand and issues which led to shortages of the recent past. Key economic factors and their impact on future availability of aluminum are discussed by constructing possible scenarios.

An analysis was made to determine which potential highway and motor vehicle safety activies were most deserving of further pursuit so as to obtain the greatest improvement in safety at the least cost. Criteria were established to guide in the rating and ranking of potential safety projects. The most significant national safety problems were identified and a description and schedule of the chosen safety projects to address those problems were prepared.

Japanese safety standards are specified by the Safety Regulations and relevant Circular Notices. MOT had revised the standards according to the first program plan for safety of 1972. Future revisions will be made according to the second program plan issued in 1980. The main emphasis will be laid down on measures for high speed driving, measures to prevent fire and safety measures for trucks. MOT will also seek the way to harmonize its standards with the UN ECE Regulations through positive participation to HP 29 of ECE. Efforts for world-wide harmonization will be made by MOT.

Increasing market penetration of driver assistance systems challenges system suppliers with ACC (Adaptive Cruise Control) and PSS (Predictive Safety Systems) functions with divergent requirements. This paper covers the technical development of a long range radar sensor that can address the requirements for high-performance systems as well as requirements for cost-efficient sensor components with robust and compact design and high quality standards, which are suited for high-volume production.

Excavator is a typical hydraulic heavy-duty human-operated machine applicable in general versatile construction operation, such as digging, ground leveling, carrying loads, and dumping loads [1]. The aim of this article is to establish the design process of a new long reach boom for the Caterpillar excavator (CAT 375) for dredging in harbors and dams. The length of both the boom and the stick in extended mode can reach up to the maximum digging depth of 17.2 m. The capacity of the bucket for this new model of long reach boom is 0.8 m3. Among common reach booms of CAT 375L, the maximum digging depth is 11.68 m [2]. In the current design, the lengths of boom and stick as well as the material properties were selected based on the maximum pressure of hydraulic circuit and stability against overturning of excavator. This special long reach boom excavator was used in Assalouyeh construction harbor.

Vegetable oils are a potential alternative to the partial or total substitution of diesel fuels. It was known that short-term engine tests have been successful with vegetable oils, however, long-term tests have revealed the fuel's limitations regarding lubricating oil contamination, deposits on engine surfaces and injection problems. In this ongoing research study, properties of palm oils and diesel blends were determined and long-term engine tests of palm oils and diesel blends were performed on a modern direct injection diesel engine at a speed of 2500 rev/min under part load condition for almost 250 hours. Results of engine torques, specific fuel consumptions, black smoke emissions and injection pump surface inspection were compared between diesel and palm oil/diesel blends. Engine performance, smoke emissions and fuel consumption were found to change slightly with running time.

A wet clutching/braking mechanism has been designed to operate as prescribed in a patent issued to R. A. Iverson in 1982 (1)*. A key element in this design is to allow high radial oil flow rates through the clutch plate stack to carry the heat generated during power absorbtion away from the clutch disks. A continuously variable transmission incorporating this new clutch was constructed and tested under contract to NASA in which the clutch assembly was found to absorb 5.78 × 10−3 KW/cm2 (0.05 HP/in2) of surface area with no supplemental oil cooling. As a result of the new design, an equal fraction of torque was transmitted through each of the disks in the clutch pack and no wear of the clutch plates was descernable after several hours of high energy rejection operation. As applied to transmissions, this design eliminates the need for torque convertors/fluid couplers and tolerates long duration of slippage.

Today’s value proposition of plug-in hybrid electric vehicles (PHEV) and battery electric vehicles (BEV) remain expensive. While the cost of lithium batteries has significantly decreased over the past few years, more improvement is necessary for PHEV and BEV to penetrate the mass market. However, the technology and cost improvements of the primary components used in electrified vehicles such as batteries, electric machines and power electronics have far exceeded the improvements in the main components used in conventional vehicles and this trend is expected to continue for the foreseeable future. Today’s weight and cost structures of electrified vehicles differ substantially from that of conventional vehicles but that difference will shrink over time. This paper highlights how the weight and cost structures, both in absolute terms and in terms of split between glider and powertrain, converge over time.

The long-term environmental and mechanical properties of adhesive intensive five door car body, using automotive grades of one component, heat curing rubber based and epoxy based adhesives have been tested and evaluated. The bodies were built in a normal production line in one of Volvo Car Corporation’s factories. The application and assembly aspects of weld-bonding on a large scale are evaluated with respect to work environment and joint quality. Properties after long-term testing of both laboratory specimens and body structures are described as well as analysis of the failure modes as a function of the adhesive bonding systems. Comparisons are made with normal production bodies.

This paper describes improvements achieved with regard to the long term stability and the system integrability of a previously described thick film NOx sensor for gasoline lean burn and diesel applications. (1, 2, 3) Durability test up to 1000 hours consisting of a temperature cycle have been carried out by a stoichiometric operating gasoline engine test bench. The NOx sensor demonstrates the NOx output shift in terms of the NOx sensitivity less than 5 % on a model gas apparatus and ± 7 % measuring accuracy in practical operating condition on a diesel engine after 1000 hours that is equivalent to approximately 60K miles driving. The integration of the control electronics for the sensor in its connector is achieved for the sensitive measuring current in the μA-range or less on vehicle applications. The developed electronics functions closed-loop controls for a tip temperature and oxygen pumps as well as a diagnosis of sensor malfunctions.

A newly developed simulation methodology for a long term, transient tractor cabin cool-down is presented in this paper. The air flow was simulated using a Lattice-Boltzmann Equation (LBE) based 3-dimensional flow solver. The conduction and radiation effects on the solid parts as well as the average cabin air temperature evolution were solved by the thermal solver, which also includes a human comfort model. The simulation results were compared with the measured experimental test data and good agreement was observed validating the developed simulation approach. The developed methodology can be applied to all other ground vehicles cabin comfort applications.

EXTENSION of motorcoach services over routes of 100 miles or more in length in all parts of the Country is shown by a map, and figures are given of the number of routes, the miles of highway over which the services are operated, running time, rates of fare charged and like data. Facilities and operating methods differentiating long-distance from suburban services are mentioned and the similarity to railroad practice pointed out. A characteristic of routes ranging from several hundred to nearly 1500 miles is that service is afforded continuously for 24 hr. per day seven days per week and many passengers ride day and night. Such long runs are broken into stages so that a driver does not work more than 8 to 10 hr. as a rule and vehicles are changed at the end of a run of a certain distance, which may vary from about 200 to nearly 750 miles.

THE creation of additional operating divisions and maintenance units, based on the California Transit Co. system originally operated by the author, which had proved successful in long-haul passenger transportation on the Pacific Coast, expanded the business so that the Yelloway Pioneer Stages, Inc., now includes about 9000 miles of route. The design of the equipment for the service was developed to meet the severe operating conditions, which demand that the same vehicle run satisfactorily over a sea-level desert and through mountainous country having an average altitude of more than 5000 ft. and, at the same time, that safety and comfort be provided for the passengers. This requires factors of strength and safety that are greatly in excess of those possessed by the ordinary commercial motorcoach.

Annual fuel use for sleeper cab truck rest period idling is estimated at 667 million gallons in the United States, or 6.8% of long-haul truck fuel use. Truck idling during a rest period represents zero freight efficiency and is largely done to supply accessory power for climate conditioning of the cab. The National Renewable Energy Laboratory’s CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck thermal management systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In addition, if the fuel savings provide a one- to three-year payback period, fleet owners will be economically motivated to incorporate them.

The authors have developed a long range version human body sensing module. This module has a high measurement accuracy with a capacitance of less than two femto Farads and can detect more distant human bodies compared with conventional sensors. Furthermore, optimizing the electrode structure of this module, noise tolerance and directivity have been improved. We produced some prototypes of this sensor module and evaluated the sensitivity of them in a vehicle. The results show that the prototype can detect a hand at the distance of 300 mm from the sensor electrode.