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Automotive Applications (automotive + application)
Selected AbstractsReliability Aspects of Microsystems for Automotive Applications,ADVANCED ENGINEERING MATERIALS, Issue 4 2009Roland Müller-Fiedler Abstract The implementation of microsystems in automotive applications is certainly one of the driving forces for the success of MEMS as an industrial technology on mass production level. In many cases, automotive systems based on microsensors are critical to safety. Consequently, microsystems have to assure an accurate, reliable, and failsafe operation during the entire lifetime of the vehicle. Since, the car represents a harsh environment for electronic or mechanical systems and components, reliability issues of MEMS have moved more and more into the focus of research and development. In particular, reliability aspects related to packaging and assembly have become a key issue in lifetime investigations. The packaging of microsystems comprises a variety of materials and material combinations, that directly affect the stability of MEMS components. Therefore, sophisticated characterization methods are needed to extract the reliability-relevant material parameters. This paper gives an introduction into investigations of the stability assessment of glass frit bonding as well as new bonding technologies based on metallic sealing of MEMS devices. [source] Semi-Solid Processing of Tailored Aluminium-Lithium Alloys for Automotive Applications,ADVANCED ENGINEERING MATERIALS, Issue 4 2007R. Sauermann Abstract This paper describes the development and evaluation of thixoformable Al-Li-Mg-based alloys performed at the collaborative research center SFB 289, RWTH Aachen. Scandium and zirconium were added to AlLi2.1Mg5.5 (A1420) with the aid of DoE (Design of Experiments), and precursor billets were manufactured by pressure induction melting (PIM). To evaluate the thixoformability of the synthesized alloys semi-solid processed connecting rods were manufactured by the rheo container process (RCP). Subsequent heat treatment raised the mechanical properties to maximum values of tensile strength, 430,MPa, yield strength of 250,MPa, and an elongation to fracture of 13,%. The RCP process was designed for the special requirements of highly reactive alloys. The paper presents the remarkable property and process benefits of the semi-solid processing of Al-Li alloys. [source] Novel Polymer Electrolyte Membranes for Automotive Applications , Requirements and Benefits,FUEL CELLS, Issue 4 2004C. Wieser Abstract During the past few years, the feasibility of using polymer electrolyte fuel cells in automotive power trains at an impressive performance level has been proven repeatedly. However, current fuel cell stacks are still largely based on decade-old polymer electrolyte membrane technology thus limiting performance, durability, reliability, and cost of the fuel cell systems. The major challenge for membrane R&D constitutes the demand for polymer electrolytes that allow for system operation at higher temperatures and lower water management requirements without increased conduction losses. None the less, demanding automotive requirements will not compromise on other properties such as mechanical and chemical stability and gas permeability. [source] Concept, Design and Manufacture of a Prototype Hydrogen Storage Tank Based on Sodium AlanateCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 8 2009C. Na Ranong Abstract In the framework of the EC project STORHY (Hydrogen Storage for Automotive Applications), the prototype of a solid storage tank for hydrogen based on sodium alanate was developed. A storage tank containing 8,kg sodium alanate was designed and manufactured with the objective of fast refueling. To obtain the optimum design of the storage tank a simulation tool was developed and validated by experiments with a laboratory-scale tubular reactor. Application of the simulation tool to different storage concepts and geometries yielded the final design. The chosen concept is modular, enabling simple scale-up. This is the basis for the future development of fuel cell vehicle storage tanks containing 5,kg of hydrogen. [source] Simultaneous input and parameter estimation with input observers and set-membership parameter bounding: theory and an automotive applicationINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 5 2006I. Kolmanovsky Abstract The paper addresses an on-line, simultaneous input and parameter estimation problem for a first-order system affected by measurement noise. This problem is motivated by practical applications in the area of engine control. Our approach combines an input observer for the unknown input with a set-membership algorithm to estimate the parameter. The set-membership algorithm takes advantage of a priori available information such as (i) known bounds on the unknown input, measurement noise and time rate of change of the unknown input; (ii) the form of the input observer in which the unknown parameter affects only the observer output; and (iii) the input observer error bounds for the case when the parameter is known exactly. The asymptotic properties of the algorithm as the observer gain increases are delineated. It is shown that for accurate estimation the unknown input needs to approach the known bounds a sufficient number of times (these time instants need not be known). Powertrain control applications are discussed and a simulation example based on application to engine control is reported. A generalization of the basic ideas to higher order systems is also elaborated. Copyright © 2006 John Wiley & Sons, Ltd. [source] Intergranular corrosion on Nd:YAG laser-welded A653 steel for automotive applicationMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 11 2004Y. M. Looi Abstract Laser welding techniques produce a narrower heat-affected zone than other conventional welding methods. However, laser welding is not exempt from high heat input during the welding process. This high heat input results in changes of the material properties including its corrosion behaviour; the formation of the heat affected zone increases the susceptibility of the material to intergranular attack. The residue of zinc at the weld due to condensation and splashing during the welding process may also influence adversely the corrosion behaviour of the material. The degree of susceptibility to corrosion strongly depends on the welding parameters. Electrochemical and microstructure characterisation were employed to study the influence of Nd:YAG (neodymium yttrium aluminium garnet) laser-welding on an A653 galvanized steel at different welding parameters. [source] Reliability Aspects of Microsystems for Automotive Applications,ADVANCED ENGINEERING MATERIALS, Issue 4 2009Roland Müller-Fiedler Abstract The implementation of microsystems in automotive applications is certainly one of the driving forces for the success of MEMS as an industrial technology on mass production level. In many cases, automotive systems based on microsensors are critical to safety. Consequently, microsystems have to assure an accurate, reliable, and failsafe operation during the entire lifetime of the vehicle. Since, the car represents a harsh environment for electronic or mechanical systems and components, reliability issues of MEMS have moved more and more into the focus of research and development. In particular, reliability aspects related to packaging and assembly have become a key issue in lifetime investigations. The packaging of microsystems comprises a variety of materials and material combinations, that directly affect the stability of MEMS components. Therefore, sophisticated characterization methods are needed to extract the reliability-relevant material parameters. This paper gives an introduction into investigations of the stability assessment of glass frit bonding as well as new bonding technologies based on metallic sealing of MEMS devices. [source] High-speed-range enhancement of switched reluctance motor with continuous mode for automotive applicationsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 7 2008M. Rekik Abstract This paper describes an original method for the elaboration of control laws for the Switched Reluctance Motor (SRM) for high-speed operation. In this case, the control optimisation relies on the choice of optimal turn-on and turn-off angles to ensure, in general, high global efficiency, in classical supply mode with full-wave voltage. Then, after showing the influence of number of turns, a new supply mode called the continuous mode is described. This mode, used with a higher number of turns, allows to reduce the inverter current rating and hence silicon requirements without compromising performance at high speed. This makes the SRM competitive compared to other technologies (synchronous and induction motors). The simulation results for a 12/8 SRM are presented and compared to those for an induction motor. Copyright © 2007 John Wiley & Sons, Ltd. [source] On the attempts to optimize the performance and cost-effectiveness of TFPM drives: a crucial challenge for the automotive industryEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 6 2005Ahmed Masmoudi Much attention is currently focused upon transverse flux permanent magnet machines (TFPMs), especially in automotive applications, in so far as, to date, they exhibit the highest power production capability. Different automotive manufacturers are currently involved in R&D programs dealing with TFPM concepts and the possibilities of their integration in electric and hybrid propulsion systems. This paper is devoted to the analysis of two R&D projects developed within the design of TFPMs intended for hybrid propulsion systems of heavy-duty vehicles. In spite of the increasing interest in TFPMs and the significant improvements brought to their earlier topologies, we can firmly state that further investigations remain to be carried out before the TFPM concepts could be regarded as a mature technology for the automotive industry. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of Superplastic Deformation of AZ31 Magnesium Alloy,ADVANCED ENGINEERING MATERIALS, Issue 9 2007K. Abu-Farha AZ31 is a magnesium alloy possessing good mechanical properties, which makes it particularly attractive for automotive applications. Yet, in order to advance the utilization of this alloy, a broad database of its superplastic behavior is needed. This work presents the results of a comprehensive study on the elevated temperature superplastic behavior of the AZ31 magnesium alloy. Flow stress, fracture strain and strain sensitivity index maps were constructed over a wide range of strain rates, covering temperatures between 325 and 450 °C. [source] Polybenzimidazole-Based Membranes as a Real Alternative to Nafion for Fuel Cells Operating at Low Temperature,ADVANCED MATERIALS, Issue 7 2008Piercarlo Mustarelli Filler up! Composite proton-conducting membranes, based on polybenzimidazole (PBI) and imidazole-derivatized silica are presented. The addition of even small amounts (,10 wt %) of filler causes an outstanding improvement in the permanent proton conductivity by a factor <103. The preparation of PBI composite membranes with basic functionalities is a promising way to make possible their use in PEMFCs operating around 120,°C, that is, the temperature required for automotive applications. [source] Ceria in catalysis: From automotive applications to the water,gas shift reactionAICHE JOURNAL, Issue 5 2010Raymond J. Gorte Abstract Ceria is a crucial component of automotive catalysts, where its ability to be reduced and re-oxidized provides oxygen storage capacity. Because of these redox properties, ceria can greatly enhance catalytic activities for a number of important reactions when it is used as a support for transition metals. For reactions that use steam as an oxidant (e.g., the water,gas-shift reaction and steam reforming of hydrocarbons), rates for ceria-supported metals can be several orders of magnitude higher than that for ceria or the transition metal alone. Because the redox properties of ceria are strongly dependent on treatment history and the presence of additives, there are significant opportunities for modifying catalysts based on ceria to further improve their performance. This article will review some of the contributions from my laboratory on understanding and using ceria in these applications. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Modeling of coupled mass and heat transfer through venting membranes for automotive applicationsAICHE JOURNAL, Issue 2 2009Amine Barkallah Abstract Experimental and theoretical approaches based on a mathematical model, have been developed to study the evolution of environmental parameters (temperature, total pressure, relative humidity, and water vapor partial pressure) inside a housing of an electronic device with a window containing a macroporous membrane. The model was based on the coupling of mass and heat transfer taking into account the effects of polarization of concentration in boundary layers. Membranes have been characterized by mercury porosimetry, liquid entry pressure measurements, scanning electron microscopy, and gas permeation. Once the model was experimentally validated, it was applied to investigate the influence of membranes on heat and mass transfer and to study the impact of the boundary layers on the global mass transport. The results demonstrated the importance of the membrane choice and dimensions to get the best temperature regulation and avoid water condensation inside an automotive electronic control unit (ECU). © 2008 American Institute of Chemical Engineers AIChE J, 2009 [source] | ||||||||||||||||