Search Results

The excellent anti-wear (AW) and oxidation inhibition properties of Zinc Dialkyl Dithio Phosphates (ZDDPs) have resulted in their extensive use in modern AW hydraulic oils. However, increasingly compact hydraulic systems utilizing high service-pressure pumps (>300kg/cm2), has lead to operating temperatures (>250°C) that have been shown to thermally degrade ZDDP into insoluble sludge [1]. This paper chronicles the development of a non-ZDDP AW hydraulic oil, and evaluates its performance relative to a ZDDP oil in the areas of sludge generation, oxidation, and AW properties. The formulation reduces sludge by 85 to 99.5%; retains more viscosity; reduces metal wear by 04-06%; and extends useful service life to at least twice that of the ZDDP-based hydraulic oil.

Liquid automatic optical particle counters (APCs) are used to monitor contamination levels in hydraulic and engine oil, to establish component and assembly cleanliness level specifications, and to determine filter efficiencies and size ratings. As a result of the recent revisions to ISO particle counter calibration, multi-pass filter test, and on-line particle counter calibration standards, it is anticipated that the quality and reliability of particle count and filter test data will improve, increasing their usefulness to the hydraulics, automotive and aerospace industries. However, the resultant redefinition of particle sizes affects how contamination levels and filter performance are reported and interpreted. The impact of these changes is discussed in this report.

The armed forces of most NATO countries are committed to a ‘single fuel’ policy for all battlefield equipment, based on diesel fuel in peacetime and avaiation kerosene in war. Motorcycles will shortly become the only land vehicles unable to comply with this policy. A programme has been undertaken to establish the feasibility of a diesel-powered motorcycle offering the all round on/off road performance required for military duties. A demonstrator motorcycle having a compact, high specific output naturally aspirated engine, capable of running on the specified fuels, has been designed and built. Evaluation by the British Army and US Marine Corps indicates that a production machine employing the technology used in the demonstrator would be capable of meeting the user's requirements. The paper describes the design approach used to produce the demonstrator machine, performance achieved and potential for further development.

This paper describes the development and manufacture of roll-off container handling systems for off-highway articulated trucks. This presentation reviews systems incorporating four unique products covering various roll-off container handling alternatives. The various components described and, depending on the style of the system, incorporated into a system are: 1. An off-highway truck “J”-Hook arrangement for picking roll-off containers up off of the ground and pulling them onto a haulage vehicle. 2. An automatic tailgate locking and opening system for roll-off containers vs. a manual vehicle driver dependent door/tailgate system. 3. A scissors lift for lifting roll-off containers to be dumped into various other vessels (railroad gondola cars, etc.). 4. A unique “J”-Hook interface for standard 20-ft. intermodal roll-off shipping containers so they can be hooked onto and handled with a “J”-Hook.

The application of open-circuit, load-sensing hydraulic systems in industrial, marine, and mobile equipment has long provided many advantages to machine designers, manufacturers, distributors, dealers, and end-user customers. Typically, the flow for such systems is provided by variable-displacement piston or vane pumps. However, in some applications, fixed-displacement gear pumps with integral load-sensing valve packages offer a more economical, and (depending on machine duty cycle and other parameters) a more efficient system. This paper will provide an overview of the design and advantages of these units, discuss the essential criteria which must be considered during the “fixed-displacement versus variable-displacement” pump selection process, and describe some typical applications.

DENSO mandated that its 13 affiliated North American facilities implement ISO 14001 by 1999. This posed a number of substantial challenges given the diversity and scope of its operations, challenges which conventional implementation approaches seemed ill-suited to handle. DENSO North America developed and executed a hybrid strategy, “system-consistency,” that may offer valuable lessons for other manufacturers confronting the task of implementing ISO 14001 in a diverse, multi-facility environment. Moreover, “system-consistency” has provided DENSO with tangible economic benefits, including substantial reductions in environmental management systems development, implementation, and re-certification costs that will amount to over $1 million within the first 3 years alone.

The use of real time cylinder pressure information in advanced diesel engine monitoring and control techniques offers the potential for improved engine reliability and performance as well as reduced levels of emissions. This paper reports the design and performance of Optrand high-temperature, long-life, and miniature fiber-optic pressure sensor that has been specifically developed for engine control and monitoring applications. For use in automotive diesel engines the sensor is preferably integrated with a fuel injector or a glow plug. Laboratory and various engine tests are reported here for small and large diesel engines demonstrating a typical +/-0.5% total error due to non-linearity, hysteresis, and thermal shock. In various engines the sensor has already demonstrated the unprecedented lifetime of 0.8 Billion-pressure cycles.

This paper provides a comparison of simulation results with experimentally measured performance data in a lean-burn engine operating with natural gas over a wide range of air-fuel ratios. The Ricardo WAVE 3.3 engine simulation code was used to predict intake and exhaust manifold pressures and flow rates, as well as cylinder pressure and engine performance parameters. Experimental data were obtained from a Ricardo Hydra single-cylinder research engine operating in a speed range of 1000 - 3000 rpm. Calculations were conducted with both a simplified mass burn-rate model, as well as a more sophisticated engine combustion model. Comparison between the two different combustion models and experimental data showed that both models were able to predict the engine performance with satisfactory accuracy under stoichiometric conditions. With increasing air-fuel ratio up to the lean limit, however, the more complete combustion model resulted in closer agreement with the experimental results.

Direct injection into open chambers of Diesel- and S.I.- Engines is considered by the experts of automotive engineering worldwide as the best way for future economy and ecology engines [1]. Beside of the best fuel saving passenger cars driven by Diesel engines, advanced Diesel like Stratified Charge Engines as the CCSC (Controlled Combustion Stratified Charge) and the MESC (Mixture Exhaust Stratified Charge) -Engines open the way for future developments. Both engines work with the following new elements: Air assisted injection for the formation of the combustible mixture in the small cavities of prechambers, where the load control is achieved by the quantity of the injected fuel without the need of throttling the charge of the main chamber as common in today's SI engines. Pulsed Jet Combustion, where at first in small cavities of prechambers a rich mixture gets ignited.

Concurrent engineering is the wave of the future in powertrain development. This paper presents a time accelerated development program to reduce emissions in a gasoline direct injection fuel combustion engine. Several approaches for positioning the injector and the spark plug including multiple plugs for each chamber were explored. Any change in the position of the fuel injector or the spark plug(s) heavily affects the water jacket's design as well as the position of the DOHC shaft's bearings. This paper describes a case study utilizing Soligen's Direct Shell Production Casting (DSPC') while integrating the development of this new cylinder head in record time, bypassing the traditional need for casting tooling. Record number of design iterations were explored in rapid turn-around time and using a paperless process of converting the CAD file of the head into functional cast and CNC machined heads. DSPC is a rapid casting process which makes conventional prototype casting obsolete.

An electromagnetic valve actuation (EVA) system was developed and applied to a Kohler Command Series engine. Engine development and testing was conducted for the purpose of evaluating the performance of the EVA-equipped engine, running on natural gas, in an engine-test laboratory environment. As part of this effort, a personal computer-based engine control system, which managed the fueling, ignition, throttling, and intake/exhaust valve control functions, was developed. The evaluation included an investigation into increasing engine power output and full load efficiency, as well as increased part load efficiency. Techniques including optimized valve events as a function of operating condition, and throttleless operation using early and late intake valve closing are presented. Engine simulation results are compared with actual engine data and presented in this paper.

This paper describes a fuel management known as engine air control as opposed to the more conventional management technique, or engine fuel control. When applied to an internal combustion engine, conventional fuel management systems utilize fuel modulation, where the human is in direct control of the intake air-throttling valve. Here, the throttle indirectly controls the airflow into the engine. The fuel management controller determines the air flowing into the engine and based on the desired air fuel ratio, calculates the appropriate amount of fuel necessary, based on the desired performance index (minimize fuel, maximize power, etc.). In an air control system, the human is in control of fuel flow as opposed to airflow. The engine management system interprets the human input as a desired fuel flow rate, and must calculate the proper amount of air necessary to obtain the desired air fuel ratio. The controller must also deliver the correct amount of fuel to the engine.

Hybrid Electric Vehicles (HEVs) have several potential advantages over traditional internal combustion engine (ICE) vehicles. They promise higher fuel economy and lower emissions without sacrificing vehicle performance and range. They can also take advantage of the existing fuel delivery infrastructure which may facilitate their acceptance by the consumer. High performance electrochemical battery systems are the most promising candidates for providing peak power for HEVs in the near future. However, the specific requirements these batteries must meet (higher specific power, good high rate charge acceptance, low self discharge) are much more stringent than for any other application. This paper summarizes general test requirements and procedures used in the development and characterization of battery packs and management system for hybrid electric vehicles. A comparison of the capabilities of existing test equipment is also given.

We describe here a hybrid electric vehicle (HEV) built by the American Electric Automobile Company (AEAC) and operated on a daily basis. The HEV was chosen over a pure electric vehicle (EV) to address the most common problems with electric vehicles: their limited range and long charging times. For example, a frequent question from potential EV buyers is: “What happens if my batteries run down while I'm on the freeway?” In order to be a viable concept at an acceptable price, this HEV design emphasized off-the-shelf components whenever possible. Furthermore, for similar considerations, a series hybrid design was utilized. The characteristics of this HEV will be described which include the platform (a 1985 VW Cabriolet) and the internal combustion power plant (a 9kVA Dyna generator powered by a 16 HP engine). This HEV has been operated for 2 years and has accumulated 24,000 km under actual driving conditions. During this evaluation period, several problems were identified and solved.

The Army is committed to hybrid electric combat vehicles for deployment in the next century. The key consideration for such systems is to minimize system volume, since interior vehicle volume, particularly under armor, is at a premium. A variety of power converters are required. It is therefore beneficial to reduce converter volume as much as possible, yet maximize efficiency, versatility and maintain high power quality. In a prior study[1], the Army Research Laboratory (ARL) determined that compact converters are feasible. The most significant finding of the study was the substantial space savings obtainable if the passive components of the filter section commonly found in standard DC link converters were eliminated. This may be done with the matrix converter, an AC to AC converter. The technology is not new, but has not been utilized extensively in the past due to the complexity of control required to efficiency operate such converters.

Quantifying Hybrid Electric Vehicle (HEV) emissions and fuel consumption is a difficult problem for a number of different reasons: 1) HEVs can be configured in significantly different ways (e.g., series or parallel); 2) the Auxiliary Power Unit (APU) can consist of a wide variety of engines, fuel types, and sizes; and 3) the APU can be operated very differently depending on the energy management system strategy and the type of driving that is performed (e.g., city vs. highway driving). With the future increase of HEV penetration in the vehicle fleet, there is an important need for government agencies and manufacturers to determine HEV emissions and fuel consumption. In this paper, several critical issues associated with HEV emissions and fuel consumption are identified and analyzed, using a sophisticated set of HEV and emission simulation modeling tools.

This investigation of the use of cryogens as energy storage media for zero emission vehicles has found that using liquid nitrogen to liquefy the working fluids of one or more closed Rankine power cycles can be an effective means for increasing motive power. System configurations are presented which can realize over 50% of the availability of liquid nitrogen without relying on isothermal expanders. A zero emission vehicle utilizing such a propulsion system would have an energy storage reservoir that can be refilled in a matter of minutes and a range comparable to that of a conventional automobile.

An optimum design has been performed to maximize the total stored energy (TSE) of a hybrid composite flywheel with a permanent magnetic rotor attached inside the flywheel. The flywheel rotor consists of multiple rings of advanced composite materials. A structural analysis has been performed considering ring-by-ring variation of material properties. The pressure from the centrifugal forces of the magnet is also considered together with the centrifugal body forces in the flywheel rotor. The size of the magnet is dependent upon the required induced voltage, and effects the pressure distribution at the inner surface of the composite rotor. An analytical solution for each ring has been obtained and expressed in terms of a symmetric stiffness matrix. Using the stiffness matrix the continuity conditions can be easily considered and a global system of equations is derived.

The International Border Electronic Crossing System (IBEX) incorporates low cost sensors on commercial vehicle braking systems to evaluate out-of-service conditions (OOS). OOS conditions include dragging, worn and inoperable brakes. Present roadside brake inspections require manual inspection under the vehicle to verify the operation and condition of the brake system components. To minimize these under-vehicle inspections, on-board sensors can monitor brake component conditions while the vehicle is in operation. Signal Processing Systems (SPS), Calspan Corporation, and Radlinski and Associates, Inc. (RAI) equipped three commercial vehicle tractors with brake shoe thermocouples and instrumented brake chambers. Brake condition data, acquired by the SPS “SmartLog” system, was recorded to a PCMCIA card and down-loaded on a weekly basis. Also recorded with the brake condition data was vehicle location at time of brake operation.

Multiplexing systems have been used in automobiles for the past decade. The use of these systems has allowed manufacturers to reduce wiring harness size, eliminate redundant sensors, and achieve a level of communication not available before. While most applications of multiplexing have been inter-modular communication, there exist many more opportunities to utilize multiplexing. These opportunities include multiplexing various user activated/interacted switches, sensors, and actuators. Multiplexing of this type is defined by the SAE as a low speed sensor/actuator bus, or Class “A” bus. The Class “A” bus addresses issues, such as: the challenge of handling increasing wiring complexity, incorporating diagnostics and testability into automotive electronic designs, facilitating the use of new switch and actuator technologies, and allowing a higher degree of systems design flexibility.