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The testing system developed will decrease the time and the costs involved in evaluating cylinder head valve bridge designs. The test uses actual data generated from engine testing to recreate the valve bridge cracks that occur during dynamometer and vehicle testing. This paper focuses on the system description, the test development, design modifications, and the test results obtained. Testing shows that this method correctly separates valve bridge designs by test cycle life using statistical methods. It is a cost effective and timely alternative to dynamometer testing.

The CBR [1] (Controlled Burn Rate) is a port deactivation concept developed by AVL and is already applied in series production cars. The benefit of this concept is the low engine-out emission (CO, HC and NOx) and good fuel economy. By creating turbulent kinetic energy at the correct time and place in the combustion chamber a rapid and stable combustion occurs which allows to run the engine well above a Lambda Excess Air Ratio of 1.5. The CBR system features two different intake ports, one charge motion port and one filling port. Additionally a device for port-deactivation (slider, butterfly) is applied. At part load points and lower engine speeds the filling port is switched off. The CBR concept was now evoluted for compact engines as CCBR - with carburetor and as CBR Light - for engines with electronic fuel injection. CCBR stands for Carbureted Controlled Burn Rate.

Hybrid electric vehicles (HEVs) are worldwide recognized as one of the best and most immediate opportunities to solve the problems of fuel consumption, pollutant emissions and fossil fuels depletion, thanks to the high reliability of engines and the high efficiencies of motors. Moreover, as transport policy is becoming day by day stricter all over the world, moving people or goods efficiently and cheaply is the goal that all the main automobile manufacturers are trying to reach. In this context, the municipalities are performing their own action plans for public transport and the efforts in realizing high efficiency hybrid electric buses, could be supported by the local policies. For these reasons, the authors intend to propose an efficient control strategy for a hybrid electric bus, with a series architecture for the power-train.

A simulation method is presented for the analysis of combustion in spark ignition (SI) engines operated at elevated exhaust gas recirculation (EGR) level and employing multiple spark plug technology. The modeling is based on a zero-dimensional (0D) stochastic reactor model for SI engines (SI-SRM). The model is built on a probability density function (PDF) approach for turbulent reactive flows that enables for detailed chemistry consideration. Calculations were carried out for one, two, and three spark plugs. Capability of the SI-SRM to simulate engines with multiple spark plug (multiple ignitions) systems has been verified by comparison to the results from a three-dimensional (3D) computational fluid dynamics (CFD) model. Numerical simulations were carried for part load operating points with 12.5%, 20%, and 25% of EGR. At high load, the engine was operated at knock limit with 0%, and 20% of EGR and different inlet valve closure timing.

The 1-D model of a radial centripetal turbine was developed for engine simulation to generalize and extrapolate the results of experiments to high pressure ratio or off-design velocity ratio using calibrated tuning coefficients. The model concerns a compressible dissipative flow in a rotating channel. It considers both bladed or vaneless turbine stators and a twin-entry stator for exhaust pulse manifolds. The experiments were used to find values of all model parameters (outlet flow angles, all loss coefficients including an impeller incidence loss) by an original method using repeated regression analysis. The model is suitable for the prediction of a turbocharger turbine operation and its optimization in 1-D simulation codes.

This paper introduces research work on 1-D model of Roots type supercharger with helical gears using 1-D simulation tool. Today, passenger car engine design follows approach of downsizing and the reduction of number of engine cylinders. Superchargers alone or their combination with turbochargers can fulfill low-end demands on engine torque for such engines. Moreover, low temperature combustion of lean mixture at low engine loads becomes popular (HCCI, PCCI) requiring high boost pressure of EGR/fresh air mixture at low exhaust gas temperature, which poses too high demands on turbocharger efficiency. The main objective of this paper is to describe Roots charger features and to amend Roots charger design.

The battery cooling system is one of the most critical parts for the safe and efficient operation of the Li-ion battery pack in EVs. Battery liquid cooling system is most commonly used. This paper represents a comprehensive study of the electric vehicle battery liquid cooling system design and performance using the 1D tool and experimental validation. The 1D model includes the battery thermal load, cooling system components, and different ambient conditions. The cooling system components are calibrated using the experimental performance data of the components. The 1D model is used to evaluate the effect of fan speed, ambient temperature, compressor speed, and coolant flow rate on the battery cooling system and to optimize the component sizing. The results are then experimentally validated in a climate chamber, and the simulation results show good agreement with experimental results. The study's findings provide a good understanding of the Li-ion liquid cooling system.

A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.

An advanced low heat rejection engine concept has successfully completed a 100 hour endurance test. The combustion chamber components were insulated with thermal barrier coatings. The engine components included a titanium piston, titanium headface plate, titanium cylinder liner insert, M2 steel valve guides and monolithic zirconia valve seat inserts. The tribological system was composed of a ceramic chrome oxide coated cylinder liner, chrome carbide coated piston rings and an advanced polyolester class lubricant. The top piston compression ring Included a novel design feature to provide self-cleaning of ring groove lubricant deposits to prevent ring face scuffing. The prototype test engine demonstrated 52 percent reduction in radiator heat rejection with reduced intake air aftercooling and strategic forced oil cooling.

Since 1978, the Agency of Industrial Science and Technology (AIST) of MITI has promoted research and development of “Large-Scale Energy Conservation Technology” popularly known as the “Moonlight Project”. As the first step, “system technology tests” using improved lead acid batteries started at Kansai Electric's Tatsumi Electric Energy Storage System Test Plant on October 1, 1986. The results showed that this system can work not only as a load-leveling apparatus but also as a high-quality power source which can support the utility power system with its load frequency control and voltage regulation capabilities. As the second step of these R&D activities, a 1MW/8MWh sodium-sulfur battery pilot plant was constructed at the same Tatsumi site. On July 11, 1991, 1000 kW× 8H facility, the largest of its type in the world, was completed and started operation. This paper describes the construction experience and operation results of the pilot plant.

Up to now, various compressor models for automotive air conditioners have been manufactured to answer the needs of car manufacturers for fuel economy and quietness. The 10PC20 compressor, developed for automotive air conditioners, is the world's first swash plate type compressor having a continuously variable displacement mechanism. The 10PC20 is aimed at realizing a large displacement compressor with a continuously variable displacement mechanism, which has not been achieved until today. To achieve this goal, the 10PC20 design is based on the swash plate type compressor, consisting of double-headed pistons, which is adaptable to a large displacement and has excellent rotating balance and durability. The 10PC20 changes its displacement continuously by changing the inclination of the swash plate (swash plate angle) continuously. (See photo. 1 and 2) The 10PC20 adopts two variable displacement principles.

The trend towards battery voltage vacuum fluorescent displays continues the technological advances in design and construction of VFD's, as they are applied to the automobile environment. With the ever increasing use of electronic displays for electronically tuned radios (ETR's), compact disc (CD) players, and other entertainment systems, advances in battery voltage displays and their associated drive circuitry have become a necessity. With the inherent advantages of low voltage operation and high information density, VFD's will continue to dominate the automobile audio markets. This paper will discuss battery voltage displays, the basic circuitry necessary to operate a vacuum fluorescent display, and comment on the “off the shelf” controller and driver circuitry available.

Inverters are solid state devices which change DC to 120VAC electricity. They are sufficiently rugged and reliable to make them practical for use on utility vehicles for operating thumpers, tools, lights and induction motor loads. The SCR type rather than the transistor type inverter is generally required for inductive and reactive loads. Static inverters operate from battery input. They provide power without running an engine, but are limited by battery capacity so work best in intermittent load applications. Dynamic inverters operate from alternator input and will handle continuous loads to 7200 watts with truck engine running.

This paper shows some aspects of the automotive voltage energy system level shift from 14 to 42 Volts. New features and prospective emissions/fuel economy requirements are creating electrical power needs in future automobiles, which today's conventional system cannot adequately supply at 14 Vdc (nominal, with a 12 Volt battery). It will be necessary to provide electric motors, DC/DC converters, inverters, battery management, and other electronic controls to meet higher voltage requirements. Suppliers must now include 42 Volt components and systems within their product range and make these new components as light, small, and cost efficient as possible. This paper is a compilation of several published works aiming to offer a synthesis to introduce this subject to the Brazilian Automotive Market.

A drivetrain model incorporating detailed crankshaft and drivetrain dynamics has been incorporated into an unsteady gas dynamic computer simulation of a single-cylinder two-stroke engine. This study examines the change in predicted engine performance caused by relaxing the conventional assumption of constant crankshaft velocity, and a comparison of results is presented. Relaxing the assumption changed the predicted brake mean effective pressures by over 10%. Experimental validation of the simulation involved mounting an engine to a test bed and driving an inertia wheel through a fully characterized drivetrain. A high-speed data acquisition system measured signals from a position encoder mounted on the crankshaft and from a non-contact torque transducer. The time and position data were used to calculate instantaneous crankshaft speed, and these results were compared to the predicted profiles. Simulation results and experimental measurements are presented and discussed.

This paper provides an overview about the consequences of a 14/42 V - Electrical Power Supply System for the Electrical Interconnection and Switching Technology. It presents design guidelines and solutions for connector systems including advanced applications like fuse and relay boxes and gives an overview of those existing connectors already suited for 42 V and even higher voltages. The problem of arcing due to the increased voltage is discussed for the case that mating and unmating under load has to be taken into consideration. Arcing also has a tremendous impact on the design of 42 V proof relays. Therefore, some basic results be presented along with proposals how these problems can be overcome by appropriate designs. Another part of the paper looks at the electrical power supply system itself. Here interconnection techniques for new battery systems are discussed. Finally, the chances for new technologies are highlighted.

The characteristics of the combustion process in an improved design of a novel spark ignition engine studied by means of Computational Fluid Dynamics are presented. The engine is designed to work at low average combustion temperatures to achieve very low NOx emissions. The engine is a two-stroke, two piston in-line engine. The main combustion occurs in four combustion pre-chambers that have an annular shape with a nozzle on the side facing the cylinder. Fuel is directly injected into the pre-chambers by using high-pressure fuel injectors. A progressive burning process is expected to keep the flame inside the pre-chambers while the fast ejection of combustion products should produce effective mixing with the cold air in the cylinder. This fast dilution should guarantee a temperature drop of the combustion products thus reducing the formation of NOx via a thermal path.

Transfer path analysis is a powerful tool to support the vehicle NVH development. On the one hand it is a fast method to gain an overview of the complex interplay in the vehicle noise generation process. On the other hand it can be used to identify critical noise paths and vehicle components responsible for specific noise phenomena. FEV has developed several tools, which are adapted to the considered noise phenomena: Powertrain induced interior noise and vibration is analyzed by VINS (Vehicle Interior Noise Simulation), which allows the deduction of improvement measures fast enough for application in the accelerated vehicle development process. Further on vehicle/powertrain combinations not realized in hardware can be evaluated by virtual installation of the powertrain in the vehicle, which is especially interesting in the context of engine downsizing from four to three or six to four cylinders.

Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.

System requirements and Interface Control Drawings (ICDs) make a variety of demands for MIL-STD-1553 remote terminals (RTs). Among these requirements are the need to ensure data integrity and sample data consistency, the need to perform bulk (multi-message) data transfers, and the need to offload the operation of the host CPU to the greatest degree possible. This latter requirement is reflected in such specifications as CPU spare bandwidth. The latest 1553 terminals provide a variety of choices for performing the different types of transfers. This paper provides a discussion of the hardware and software techniques for achieving these objectives. Three different schemes for RT subaddress memory management are presented: single message, circular buffer, and double buffered. For receive and transmit messages, these include fully synchronous single message transfers, asynchronous single message transfers, and multi-message transfers.