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Diesel engines, especially CR (Common Rail) DI (Direct Injection) TCI (Turbo Charged Inter-cooled), share a wide acceptance in the passenger car market due to the enormous torque and flexibility at low engine speed. A pre - condition for the use of a diesel engine in a motorcycle is that the disadvantages like combustion noise and visible smoke are reduced or eliminated. Moreover the fuel economy and performance characteristics of a diesel engine are dedicated to be used in a touring or large displacement motorcycle. The AVL engine concept is the first high performance diesel engine to be specially designed for motorcycles in terms of packaging and styling. To compensate for the limited engine speed range a gearbox with a wide ratio spread is required. This leads to a manual transmission with at least 6 gears or an automatic transmission. For the AVL concept an AMT (Automated Manual Transmission) was selected.

General Motors Powertrain Division has developed the next generation big block V8 engine for introduction in the 1996 model year. In addition to meeting tighter emission and on-board diagnostic legislation, this engine evolved to meet both customer requirements and competitive challenges. Starting with the proven dependability of the time tested big block V8, goals were set to substantially increase the power, torque, fuel economy and overall pleaseability of GM's large load capacity gasoline engine. The need for this new engine to meet packaging requirements in many vehicle platforms, both truck and OEM, as well as a requirement for minimal additional heat rejection over the engine being replaced, placed additional constraints on the design.

General Motors Powertrain Group (GMPTG) has developed an all new small block V8 engine, designated LS1, for introduction into the 1997 Corvette. This engine was designed to meet both customer requirements and competitive challenges while also meeting the ever increasing legislated requirements of emissions and fuel economy. This 5.7L V8 provides increased power and torque while delivering higher fuel economy. In addition, improvements in both QRD and NVH characteristics were made while meeting packaging constraints and achieving significant mass reductions.

Most of current jet aircraft circulate fuel on the airframe to match heat loads with available heat sink. The demands for thermal management in wide range of air vehicle systems are growing rapidly along with the increased mission power, vehicle survivability, flight speeds, and so on. With improved aircraft performance and growth of heat load created by Aircraft Mounted Accessory Drive (AMAD) system and hydraulic system, effectively removing the large amount of heat load on the aircraft is gaining crucial importance. Fuel is becoming heat transfer fluid of choice for aircraft thermal management since it offers improved heat transfer characteristics and offers fewer system penalties than air. In the scope of this paper, an AMESim model is built which includes airframe fuel and hydraulic systems with AMAD gearbox of a jet trainer aircraft. The integrated model will be evaluated for thermal performance.

The electric power steering (EPS) is increasing its number since there are many advantages compared to hydraulic power steering. The EPS saves fuel and eliminates hydraulic fluid. Also, it is more suitable to the cooperation control with the other vehicle components. The EPS is now expanding to the heavier vehicle with the advance in the power electronics. In order to meet customer's needs, such as down-sizing, lower failure rate and lower price, we have developed the new motor control unit (MCU) for the EPS. The motor and the electric control unit (ECU) were integrated for the better installation. We adopted new technologies of redundant 2-drive design for more safe EPS. “2-drive Motor Control technology” which consists of dual winding, two torque sensors and two inverter drive units. In our developed MCU, even if there is a failure in one of the drive unit, the assistance of the EPS can be maintained with the other drive unit.

After the first appearance of LED rear lamps, which employed mainly two-dimensional arrays of LEDs, the request of stylists and OEMs to have three-dimensional LED alignment has increased strongly. Development of more powerful LEDs and new packaging and assembly technologies now allows for a three-dimensional assembly of the LEDs, giving an impression of depth and enabling the LEDs to follow even extreme curvatures. This gives great customer satisfaction in terms of styling, but the disadvantage is that the cost for the three-dimensional LED alignment increases significantly. To counteract this development, we have developed a light guide technology approach (so-called 2.5 D) to combine a cost efficient LED assembly process with the flexibility of a 3 D arrangement of the light sources. Thus, we can use standard planar FR4 (Flame Resistant 4) LED printed circuit boards with arbitrary LEDs and do not depend on a certain assembly technology.

Fixed displacement pumps will continue to be a popular choice for hydraulic system designers for decades to come. These pumps are used in almost every industrial and mobile market segment and are generally less expensive than comparable variable displacement type pumps. Fixed displacement “Vane Type” pumps are especially popular because of their low noise characteristics as well as their inherent repair features. The demand for “Vane Type” fixed displacement pumps continues to grow in all market segments. Because of this continued demand, a new design of “fixed displacement vane pumps” is being developed. These pumps, designated the VPF Series, are targeted to offer continuous operating pressures up to 280 BAR with displacements from 40 to 215 cc/rev.

Electrical Air Conditioning Systems for 42 V vehicles will provide many benefits in terms of Environment protection, car Architecture, cabin Comfort and overall Safety. E-A/C Systems essentially differ from conventional ones by the use of electrical compressors. First of all, they will be particularly well adapted to new powertrains, helping to make them more environmentally friendly. Accurate control and high efficiency under the most common thermal conditions will reduce the A/C impact on fuel consumption. Besides, higher sealing integrity will cut emissions of refrigerant during normal operation and maintenance. Secondly, the use of an electrically driven compressor (EDC) will suppress a belt, and will reduce the packaging constraints. This will help to design new vehicle architectures. Thirdly, the electrification of air conditioning will allow better thermal comfort. In particular, E-A/C Systems provide a good opportunity for cabin pre-conditioning.

J I Case Company has produced four-wheel-drive agricultural tractors since 1964. In 1984 however, the flagship of the Case fleet changed hands. Rising labor costs and larger farming operations spearheaded the need for a more efficient larger tractor. January 1984 marked the introduction of the largest four-wheel-drive tractor in the history of Case, the 4994, a 400-gross engine horsepower tractor, Figure 1. Sheer horsepower alone however, would not meet the requirements of today's farming operations. Case Engineering realized that tomorrows tractors must have sufficient power to handle the wide variety of attachments available. They also realized that along with the unmatched power must come precise control of the attachment. These advancements in farming have required improvements to the tractor hydraulic system. This paper describes the hydraulic system of the 4994, Case's new flagship.

Flight control technology for 8000 psi has emerged almost simultaneously with new fire-resistant hydraulic fluids, such as MIL-H-83282 and CTFE. A proliferation of industry recommendations has resulted in a wide variety of mechanisms for solving associated actuator design problems, including tighter clearances, special seals, finishes, materials, and many others. As there are few common agreements on the issues, an extensive three-phase test program was undertaken to attempt to corroborate some of these approaches or suggest others that may be better or more cost effective.

An 8000 psi test program was conducted to resolve conflicts and issues surrounding the use of CTFE and MIL-H-83282 fluid with vented and unvented actuator rod seals. Each of the four possible combinations had unique problems and each responded to appropriate corrections including new backup rings designed to operate with standard clearances. It was concluded that all combinations were viable within certain limits. Advantages and disadvantages of each configuration were identified and specific recommendations made for both dynamic and static seals within the context of existing military specifications.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

Shortly after World War II, as aircraft became more sophisticated and power-assist, flight-control functions became a requirement, hydraulic system operating pressures rose from the 1000 psi level to the 3000 psi level found on most aircraft today. Since then, 4000 psi systems have been developed for the U.S. Air Force XB-70 and B-1 bombers and a number of European aircraft including the tornado multirole combat aircraft and the Concorde supersonic transport. The V-22 Osprey incorporates a 5000 psi hydraulic system. The power levels of military aircraft hydraulic systems have continued to rise. This is primarily due to higher aerodynamic loading, combined with the increased hydraulic functions and operations of each new aircraft. At the same time, aircraft structures and wings have been getting smaller and thinner as mission requirements expand. Thus, internal physical space available for plumbing and components continues to decrease.

Positive displacement pumps are key components in automotive and hydraulic fluid systems, often serving as the primary power source and a major source of noise in both on-highway and off-highway vehicles. Specifically, gerotor pumps are widely utilized in vehicle coolant, lubricating, and other fluid systems for both conventional and electric powertrains. This study introduces a novel method for predicting noise in gerotor pumps by combining a Computational Acoustics (CA) approach with a 3D Computational Fluid Dynamics (CFD) approach, both implemented in the Simerics–MP+ code. The CFD simulation includes the detailed transient motion of the rotors (including related mesh motion) and models the intricate cavitation/air release phenomena at varying pump speeds. The acoustic simulation employs a Ffowcs–Williams Hawkings (FW–H) integral formulation to predict sound generation and propagation based on the detailed flow field predictions from the CFD model.

As a basic tool for fundamental studies on combustion and heat transfer in diesel engines, a new rapid compression machine with a cylinder bore of 200 mm was developed which can realize in it a free diesel flame in a quiescent atmosphere, a diesel flame in a swirl, and a diesel flame impinging on the wall. The piston of this machine is driven by high pressure nitrogen, and its speed is controlled by a sophisticated hydraulic system. This paper describes the details of the mechanism and performances of the machine, and presents some examples of studies conducted with this machine.

This paper describes how airplane control surface rate limiting can enable a ‘cliff-like’ onset of Pilot-Induced Oscillation, (P.I.O.) and how the danger can be erased by implementation of Conditionally Enabled Phase Compensated Rate Limiters, (PCRLs), in the design of the airplane's flight control system. The application is particularly important for large airplanes where control surface actuator sizing and the associated hydraulic system volumetric flow rate capability cannot be generously over-sized without large weight and cost penalties. It is shown that the PCRL can remain inactive during normal airplane operations where RMS control commands are relatively small thus avoiding adverse control surface response effects that have hindered earlier PCRL acceptance.

In practical applications of ammonia SCR aftertreatment systems using urea as the reductant storage compound, one major difficulty is the often constrained packaging envelope. As a consequence, complete mixing of the urea solution into the exhaust gas stream as well as uniform flow and reductant distribution profiles across the catalyst inlet face are difficult to achieve. This paper discusses a modeling approach, where a combination of 3D CFD and a lumped parameter SCR model enables the prediction of system performance, even with non-uniform exhaust flow and ammonia distribution profiles. From the urea injection nozzle to SCR catalyst exit, each step in the modeling process is described and validated individually. Finally the modeling approach was applied to a design study where the performance of a range of urea-exhaust gas mixing sections was evaluated.

In order to reduce fuel consumption, companies have been looking at hybridizing vehicles. So far, two main hybridization options have been considered: electric and hydraulic hybrids. Because of light duty vehicle operating conditions and the high energy density of batteries, electric hybrids are being widely used for cars. However, companies are still evaluating both hybridization options for medium and heavy duty vehicles. Trucks generally demand very large regenerative power and frequent stop-and-go. In that situation, hydraulic systems could offer an advantage over electric drive systems because the hydraulic motor and accumulator can handle high power with small volume capacity. This study compares the fuel displacement of class 6 trucks using a hydraulic system compared to conventional and hybrid electric vehicles. The paper will describe the component technology and sizes of each powertrain as well as their overall vehicle level control strategies.

Environmentally friendly fuels and lubricants research on hydraulic fluids, engine oils, greases and industrial applications is of interest to government agencies and manufacturers of equipment, engines and vehicles. The key to increasing the use of renewable natural resources is developing fluids of equivalent performance to petroleum base products, at an acceptable product cost. The well known drawbacks of vegetable oils are oxidation stability and low temperature properties. This study compares commercial fluids and laboratory formulations as to their rheological properties and uses different approaches to solve both the low temperature and the oxidative stability problems. Frictions and wear characteristics of the fluids are evaluated and several fluids are compared laboratory bench tests.

Mobile hydraulic systems traditionally operate under severe conditions in a wide range of climates. The component manufacturer's prime consideration in the selection of hydraulic oils for such service is the successful operation of the hydraulic system. Knowledge of his components and broad experience gained in their utilization emphasizes certain characteristics of oils that will aid the manufacturer in wedding the hardware into a system meeting the design criteria. Many types of oils, other than those specifically formulated for hydraulic systems, are being used for mobile hydraulic service. Among the more widely used are automotive and diesel engine oils and automotive transmission fluids. The major properties and characteristics of the fluids to be considered are wear protection, viscosity, fluid stability, rust protection, and filterability. These factors will be discussed in reference to their effect on component and system operation.