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Nowadays automobiles are getting smart and there is a growing need for the physical behavior to become part of its software. This behavior can be described in a compact form by differential equations obtained from modeling and simulation tools. In the offline simulation domain the Functional Mockup Interface (FMI) [3], a popular standard today supported by many tools, allows to integrate a model with solver (Co-Simulation FMU) into another simulation environment. These models cannot be directly integrated into embedded automotive software due to special restrictions with respect to hard real-time constraints and MISRA compliance. Another architectural restriction is organizing software components according to the AUTOSAR standard which is typically not supported by the physical modeling tools. On the other hand AUTOSAR generating tools do not have the required advanced symbolic and numerical features to process differential equations.

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.

ENGINE noise has become an increasing problem with the higher and higher compression ratios of present-day automotive engines. Because fuel octane number cannot be raised indefinitely, the problem is one of engine design and selection of crankcase lubricating oils and gasoline formulations, the authors think. This paper describes investigations into the cause of spark knock, wild ping, rumble, and the added problem of hot-spot surface ignition (which also intensifies as compression ratios increase). The authors have found gasolines with phosphorous additives, used with properly formulated multiviscosity lubricating oils, provide a partial answer to the problem of engine rumble. The authors conclude that very exact tailoring of fuels, lubricants, additives, and engines will be necessary to prevent engine noise if compression ratios continue to rise.

mDSF is a novel cylinder deactivation technology developed at Tula Technology, which combines the torque control of Dynamic Skip Fire (DSF) with Miller cycle engines to optimize fuel efficiency at minimal cost. mDSF employs a valvetrain with variable valve lift plus deactivation and novel control algorithms founded on Tula’s proven DSF technology. This allows cylinders to dynamically alternate among 3 potential states: high-charge fire, low-charge fire, and skip (deactivation). The low-charge fire state is achieved through an aggressive Miller cycle with Early Intake Valve Closing (EIVC). The three operating states in mDSF can be used to simultaneously optimize engine efficiency and driveline vibrations. Acceleration performance is retained using the all-cylinder, high-charge firing mode.

This paper deals with the Coupled thermo mechanical analysis of a cylinder head, cylinder block and crank case with the liner of an uprated engine. The existing engine develops 780 hp output with mechanical driven supercharger and the engine is uprated to 1000 hp by replacing the supercharger with a turbocharger and new Fuel injection equipment. For uprating any engine, the piston and cylinder head are the most vulnerable members due to increased mechanical and thermal loadings. Mechanical loading is due to the gas pressure in the gas chamber and its magnitude can be judged in terms of peak pressure. Thermal loading is due to temperature and the heat transfer conditions in the piston surface, cylinder liner and the cylinder head. The relative importance of the various loads applied on the head and cylinder block in operation are assessed and a method of predicting their influence on the structural integrity of the components described.

PEARLITIC malleable iron crankshafts are being used in the new Pontiac engine as a result of recent developments. This paper discusses the physical properties of pearlitic malleable iron such as elastic modulus, fatigue endurance, and tensile strength. According to the author, definite machining economies result from using pearlitic malleable iron crankshafts.

SIMULTANEOUS RECORDINGS of cylinder pressure, audible sound, and crankshaft motion have shown that rumble is a noise associated with bending vibrations of the crankshaft. The vibrations are caused by abnormally high rates of pressure rise near the top dead center piston position. In this study the high rates of pressure rise were obtained by inducting deposits into the the engine. Thud is a torsional vibration of the crankshaft, similar in sound to rumble but resulting from much earlier occurrence of the maximum rates of pressure rise. Rumble vibrations consisted of a fundamental frequency of 600 cps and higher harmonics in the 11/1 compression ratio V-8 laboratory engine used in the investigation. The audible noise of rumble was predominantly composed of the second harmonic or about 1200 cps.

This recommended practice prescribes clear and consistent labeling methodology for communicating important xEV high voltage safety information. Examples of such information include identifying key high voltage system component locations and high voltage disabling points. These recommendations are based on current industry best practices identified by the responder community. Although this recommended practice is written for xEVs with high voltage systems, these recommendations can be applied to any vehicle type.

Propulsion system control algorithms covering the functional needs of xEV propulsion (‘x’ donates P0-P4 configurations) systems are presented in this paper. The scope and foundation are based on generic well-established HEV controller architectures. However, unlike conventional HEV (series, parallel and power split) powertrains, the next generation of integrated electric propulsion configurations will utilize a single micro controller that supports multiple control functions ranging from the electric machines, inverters, actuators, clutch solenoids, coolant pumps, etc. This presents a unique challenge to architect control algorithms within the AUTOSAR framework while satisfying the complex timing requirements of motor/generator-inverter (MGi) control and increased interface definitions between software components to realize functional integration between the higher level propulsion system and its sub-systems.

This study proposes a novel biofuel for spark ignition (SI) engine, α-pinene (C10H16), which is non-oxygenated and thus has a gravimetric energy density comparable to that of hydrocarbon fuels. The ignition characteristics of α-pinene were evaluated in an ignition quality tester (IQT) under standard temperature and pressure conditions. The measured ignition delay time (IDT) of α-pinene is 10.5 ms, which is lower than that of iso-octane, 17.9 ms. The estimated research octane number (RON) for pinene from IQT is 85. A temperature sweep in IQT showed that that α-pinene is less reactive at low temperatures, but more reactive at high temperatures when compared to isooctane. These results suggest that α-pinene has high octane sensitivity (OS) and is suitable for operation in turbocharged SI engines. With these considerations, α-pinene was operated in a single cylinder SI engine.

Dynamic skip fire (DSF) has shown significant fuel economy improvement potential via reduction of pumping losses that generally affect throttled spark-ignition (SI) engines. In DSF operation, individual cylinders are fired on-demand near peak efficiency to satisfy driver torque demand. For vehicles with a downsized-boosted 4-cylinder engine, DSF can reduce fuel consumption by 8% in the WLTC (Class 3) drive cycle. The relatively low cost of cylinder deactivation hardware further improves the production value of DSF. Lean burn strategies in gasoline engines have also demonstrated significant fuel efficiency gains resulting from reduced pumping losses and improved thermodynamic characteristics, such as higher specific heat ratio and lower heat losses. Fuel-air mixture stratification is generally required to achieve stable combustion at low loads.

This paper presents a new design method for solving the vehicle vibration problem induced by engine drive, by using a μ-synthesis. We have tried the active control of engine mounts to insulate the vibration of engine. We experimented on the effects by using computer simulation and vibration simulator. Computer simulation results show that resonance peak can be effectively reduced. We have also confirmed the effect of vibration simulator, which shall be reported in this paper.

This Life Support Laboratory consists of a simulator of the spacecraft called Nautilus, which houses Air Revitalization Subsystem, Atmospheric Control and Supply, and Fire Detection and Suppression in the Equipment Area. There are supporting facilities including a Human Metabolic Simulator, simulated Low and Moderate Temperature Coolant Loop, chemical analysis bench, purified water supply, vacuum and gas supplies. These facilities are scheduled to be completed and start to operate for demonstration purposes by March 2005. There are an ARES Ground Model (AGM) and a Trace Contaminant Control Assembly in the ARS. The latter will be integrated with the AGM and a Condensing Heat Exchanger. The unit of AGM is being engineered, built, and will be delivered in early 2005 by EADS Space Division. These assemblies will be operated for sensitivity analysis, integration and optimization studies. The main goal is the achievement for optimal recovery of oxygen.

For 1974, Ford Motor Company is providing, as standard equipment, a solid state ignition system on all 400 CID and 460 CID engines as well as on all California vehicles equipped with 200 through 351 CID engines. This paper explains the Ford solid state ignition system and the objectives and design philosophy that was used in the development of the system. Further, a review of the design and production validation test plans is discussed. With this background, specific examples of the effectiveness of complete problem analysis for fundamental cause and corrective action is presented in addition to control methods and evaluation of corrective action. This problem analysis system allowed this automotive electronic product to go into production with a high degree of confidence in meeting the reliability goals.

This paper discusses the use of electromechanical devices as the kinematic portions of a microprocessor based gas turbine control system. Specific applications are: 1. An electric motor driven, positive displacement pump, which provides metered high pressure fuel to the distribution manifold. Fuel metering to be provided by varying the motor angular velocity. 2. An electric motor driven lube oil pump. 3. Electromechnical actuators for motion and control of compressor and power turbine variable geometry. 4. A starter/generator integral with the gas generator. Topics covered include: Comparison to conventional hydro-mechanical systems. Response characteristics of the fuel pump and actuator systems. Brushless D.C. motor characteristics. Power electronics requirements for brushless D.C. motors. Control electronics interface with brushless D.C. motor systems. Reliability and maintainability issues. Diagnostic/prognostic enhancements.

A new method for the structural study of long hydraulic cylinders has been developed. The rational analysis, taking cognizance of most known conditions and disturbances, is capable of an iterative type solution by computer. Some examples of its use are given, illustrating the effects of stroke length and mounting position on stresses, deflections, internal bearing loads, and critical axial load.

Ammonia is one of the most useful compounds that react with NOx selectively on a catalyst, such as V2O5-TiO2, under oxygen containing exhaust gas. However ammonia cannot be stored because of its toxicity for the small power generator in populated areas or for the diesel vehicles. A new concept for NOx reduction in diesel engine using ammonia is introduced. This system is constructed from the hydrogen generator by fuel reformer, the ammonia synthesizer, SCR catalyst for NOx reduction and the gas injection system of reformed gas into the cylinder. Experimental results show that, the SCR catalyst provides a very high rate of NOx reduction, reformed gas injection into cylinder is very effective for particulate reduction. WHEN CONSIDERING INTERNAL COMBUSTION ENGINES of the 1990's the question of how to harmonize the engine with the natural environments is one of the greatest problems. The internal combustion engine changes a substance into energy via its explosive combustion.

Due to the rising costs of fuel and increasingly stringent regulations, auto makers are in need of technology to enable more fuel-efficient powertrain technologies to be introduced to the marketplace. Such powertrains must not sacrifice performance, safety or driver comfort. Today's engine and powertrain manufacturers must, therefore, do more with less by achieving acceptable vehicle performance while reducing fuel consumption. One effective method to achieve this is the extreme downsizing of current direct injection spark ignited (DISI) engines through the use of high levels of boosting and cooled exhaust gas recirculation (EGR). Key challenges to highly downsized gasoline engines are retarded combustion to prevent engine knocking and the necessity to operate at air/fuel ratios that are significantly richer than the stoichiometric ratio.