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Experimental and numerical approaches were adopted to understand flow behavior and performance of centrifugal fans in an automotive HVAC blower system. This work is directed at improving the performance of a conventional forward-curved centrifugal fan for a given small scroll casing. Recent requirements in the design of the multiblade centrifugal fan being used in automotive HVAC blowers are not only higher pressure rise and lower noise, but also better packaging in the automobile cabin. In order to meet these requirements, among various well-known design factors affecting the fan performance, principal parameters related to the rotor shape were modified and detailed flow analysis was carried out. Measurements have been made by means of a miniature five-hole probe and a pressure scanning system connected to an online data acquisition system.

This paper describes a new 4.5-Liter V8 engine, VK45DE, which was developed for the use in the Infiniti Q45 sporty luxury sedan. The VK45DE engine, the replacement of the VH41DE for the Infiniti Q45 2000 model, is a new generation V8 engine that produces high output power at top-end speed and also generates ample torque at low and middle engine speed. Furthermore, this engine achieved best in class quietness that is pleasing the customer throughout the range of loads and speeds. Development efforts were focused on how to highly balance the need for performance with the need for quietness and smoothness. This paper provides details of this VK45DE engine as well as highlights of individual technologies that support highly balanced performance of this engine.

This paper describes the new inline 4-cylinder QR engine series that is available in 2.0-liter and 2.5-liter versions. The next-generation QR engine series incorporates new and improved technologies to provide an optimum balance of power, quietness and fuel economy. Its quiet operation results from the adoption of a compact balancer system and the reduced weight of major moving parts. Power and fuel economy have been enhanced by a two-stage cooling system, a continuous variable valve timing control system, a dual close coupled catalyst system, electronic throttle control and an improved direct-injection system. The latter includes an improved combustion chamber concept and improved fuel spray characteristics achieved by driving the injector by battery voltage. A lightweight and compact engine design has been achieved by adopting a high-pressure die cast aluminum cylinder block, resin intake manifold and rocker cover and a serpentine belt drive.

Due to environmental and legislative concerns, less polluting and more efficient vehicle powertrain systems must be developed. A first step is a simple, low cost system such as the presented Engine Stop-Start (ESS) system. A 1.9 liter four-cylinder spark-ignition engine with a four-speed automatic transmission was modified to enable fuel off-on transitions during decelerations and stops. Additional hardware includes a 7 kW electric motor-generator, a power electronics module with an inverter and a DCDC converter, a 36 Volt nominal battery system, and minor modifications to the transmission. A control scheme was developed which takes advantage of the system's fuel saving potential while minimally affecting driveability. Tests have shown EPA City fuel economy gains of approximately 12-14 percent while maintaining the same emissions classification. The EPA Highway fuel economy was increased by approximately 1 percent.

The design of the newly developed Toyota AZ series 4 cylinder engine has been optimized through both simulations and experiments to improve heat transfer, cooling water flow, vibration noise and other characteristics. The AZ engine was developed to achieve good power performance and significantly reduced vibration noise. The new engine meets the LEV regulations due to the improved combustion and optimized exhaust gas flow. A major reduction in friction has resulted in a significant improvement in fuel economy compared with conventional models. It also pioneered a newly developed resin gear drive balance shaft.

The shape and configuration of the air ventilation system determines the ventilation performance while influencing the design and structure of a car. It is therefore necessary to decide the configuration of the air ventilation system in the early stages of design. We tried to analyze the pressure level of the ventilation ducts from the aerodynamics simulation results added to the cowl top which had the ventilation intake duct, and so on. Thus we succeeded in designing a new development process that can be used to predict the ventilation performance in a shorter time without the use of prototypes.

Aqua-ammonia absorption refrigeration cycle and R-134a Vapor jet-ejector refrigeration cycle for automotive air-conditioning were studied and analyzed. Thermally activated refrigeration cycles would utilize combustion engine exhaust gas or engine coolant to supply heat to the generator. For the absorption system, the thermodynamic cycle was analyzed and pressures, temperatures, concentrations, enthalpies, and mass flow rates at every point were computed based on input parameters simulate practical operating conditions of vehicles. Then, heat addition to the generator, heat removal rates from absorber, condenser, and rectifying unit, and total rejection heat transfer area were all calculated. For the jet-ejector system, the optimum ejector vapor mass ratio based on similar input parameters was found by solving diffuser's conservation equations of continuity, momentum, energy, and flow through primary ejector nozzle simultaneously.

Fulfillment of SULEV standards without catalyst - this is a target engineers at IAV have been working on since the middle of the 1990s. The core of this development is an advanced steam engine with a high performance burner. This burner features extremely low raw pollutant emission. This paper describes new solutions that were found to solve the challenging tasks in the development of such an engine concept.

This paper will describe the BorgWarner Interactive Torque Management (ITM) system for FWD based AWD systems as well as the utilization of P/M technology for critical components within this system. The ITM is an electro-mechanical coupling device. The device consists of an electromagnet, ball ramp and wet clutch system. The system can be mounted anywhere in the drive line as well as integrated into components such as transfer cases and transaxles. The clutch actuation force is dependent on the current applied to the electromagnetic coil, providing a truly variable torque transfer device. The decision to make extensive use of P/M technology in the structural portion of this system was based on the net shape capability and weight reduction combined with the ability to chose from a wide range of engineered materials that resulted in the most economical total system package.

Connecting rods manufactured by the Precision Powder Forged (P/F) process offer several distinct advantages over those produced by all other methods including the state-of-the-art forged steel process. Precision P/F connecting rods have mechanical properties equivalent to those made from forged steel, with the added benefits of greater design flexibility, superior dimensional and weight precision, simplified finish machining and assembly, better machinability, and increased consistency because of highly stable metallurgy and a robust and reliable manufacturing process. The inherent flexibility of the P/F process also facilitates tailoring materials to achieve the optimal balance of strength and machinability for a given application. In combination, these advantages result in a product that requires less capital investment for finish machining, is more environmentally conscious by generating substantially less waste, exhibits better total performance, and has lower total cost.

Nondestructive test methods have focused on specific and narrow properties of critical dimension, hardness, visual indications, or localized crack detection, while missing significant structural characteristics not apparent without destructive test. Multi-frequency resonant inspection is a new technology, which accomplishes a quantitative, whole-body, structural analysis using natural mechanical resonances of a powder metal part. The technology is applicable to a wide range of product size and geometries, and has been used successfully on powder metal connecting rods, timing gears, ABS rings, exhaust flanges, gerotors, and more. This paper describes measurement and application fundamentals in context of a connecting rod study on production parts. Data is presented which demonstrate the ability to detect structural defects in sintered powder metal parts.

A feasibility study is presented concerning detailed vehicle modeling, including submodels for engine, transmission mechanics and hydraulics, as well as three-dimensional chassis behavior. The study was conducted jointly by Ford Motor Company, Dynasim AB and DLR. The results demonstrate that complex behavioral models of each subsystem can be developed, used and validated independently from each other, and finally assembled together to an overall model. Therefore, this approach could be the basis to establish modeling standards that allow collaboration between model developers throughout the automotive industry.

A thermal management system for heavy duty diesel engines is presented for maintaining acceptable and constant engine temperatures over a wide range of operational conditions. It consists of a computer controlled variable speed coolant pump, a position controlled thermostat, and a model-based control strategy. An experimentally validated, diesel engine cooling system simulation was used to demonstrate the thermal management system's capability to reduce power consumption. The controller was evaluated using a variety of operating scenarios across a wide range of loads, vehicle speeds, and ambient temperatures. Three metrics were used to assess the effects of the computer controlled system: engine temperature, energy savings, and cab temperature. The proposed control system provided very good control over the engine coolant temperatures while maintaining engine metal temperatures within a desired range.

This paper introduces the new 1.6L engine family, designed and developed by the Chrysler group of DaimlerChrysler Corporation in cooperation with BMW. An overview of the engine's design features is provided, with a detailed review of the performance development process with emphasis on airflow, combustion, thermal management and friction. This information is presented, to provide an understanding of how the engine simultaneously achieves outstanding levels of torque, power, fuel consumption, emissions and idle stability. The use of analytical tools such as Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) in the optimization of the engine is shown.

Engineers use phenomenological simulation models to determine engine performance. Using these models, we can predict with reasonable accuracy the heat release rate mechanism inside the engine cylinder, which enables us to obtain a prediction of the pressure history inside the engine cylinder. Using this value and the volume change rate of the combustion chamber, we can then estimate the indicated power output of the engine. However, in order to obtain the brake engine power output we must have an indication for the mechanical losses, a great part of which are friction losses. Up to now various correlations have been proposed that provide the frictional mean effective pressure as a function mainly of engine speed and load. These correlations have been obtained from the processing of experimental data, i.e. experimental values for the indicated and brake power output of engines.

After an absence of nearly two decades from General Motors vehicles, a state-of-the-art all new inline six cylinder engine will be introduced for the 2002 model year as the standard engine in a new line of midsize Sport Utility Vehicles (SUV's). The new VORTEC 4200 I6 Engine (Figure 1) brings the technical sophistication of premium passenger car engines to the truck market delivering power exceeding most competitor's V8's, with exceptional low and midrange torque, yet providing best in class fuel efficiency. It is designed to provide a high level of reliability, emit low emission levels, exhibit quiet, smooth, and refined engine operation, and is lightweight. The inline configuration provides an elegant solution to meeting customer demands with premium technology. Features include dual overhead cams - four valves per cylinder, variable exhaust valve timing, all aluminum construction for the cylinder block and cylinder head, and electronic throttle control.

The combination of physical models of an advanced engine control system was proposed to obtain sophisticated combustion control in ultra-lean combustion engines, including homogeneous compression-ignition and activated radical combustion. Physical models of intake, combustion (including engine thermodynamics), and transmission were incorporated, in which the effects of residual gas from prior cycles on intake air mass and combustion were taken into consideration. Control of the in-cylinder air/fuel ratio, exhaust temperature and engine speed during start, post-start and gear shifting phases was investigated using simulations.

A main requirement for a satisfactory function and service life of a forged powder metal connecting rod is the fatigue strength. Fatigue strength mainly depends on design, material, microstructure, and surface condition. Much work has been accomplished to optimize these factors, but still a variety of surface defects such as localized porosity, roughness, oxide penetration, decarburization, etc., can be developed during manufacturing. These surface defects impact the fatigue strength in various ways. The impact of the decarburized layer depth on the fatigue life of a forged powder metal connecting rod is the focus of this work. Several connecting rods were submitted to a Weibull test at the same loading pattern. After the fatigue tests, the connecting rods were divided into groups with different decarburized layer depths. Both Maximum Likelihood Estimates (MLE) and Rank Regression (RR) techniques were used to analyze test results from all the groups obtained.

Malleable and ductile cast irons are used extensively in automotive applications such as clutches, gears, carriers, shafts, bearings, cam, racers, hubs, etc. Recently developed P/M materials can be processed cost efficiently to replace malleable and ductile iron castings. An UTS in excess of 1240 MPa and a YS in excess of 825 MPa can be achieved with one of these new materials. These tensile properties can be coupled with elongations over 2% and impact energies over 25 Joules. This presentation will cover processing routes for these new materials and will identify parts that may benefit from this new technological advancement.

A new category of hypereutectic aluminum liners, made by PM route is now available on the market (SILITEC) and it is successfully applied to high-pressure die casting process to produce open deck cylinder blocks. The claimed achievable engine performances over cast-iron liners (weight saving, reduction of oil consumption, optimal heat transfer, wear and friction losses reduction) justify the interest of automotive industry in developing such a technology. The paper will present the experience and the achieved results in permanent mold gravity casting with Silitec liners, where metal flow definition and temperature distribution control make the casting technique more challenging for the manufacturing of closed deck cylinder blocks.