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Accelerated market penetration of plug-in electric vehicles (PEVs) is presently restricted by the high cost of batteries. Deployment of grid-connected energy storage, which could increase the reliability, efficiency, and cleanliness of the grid, is similarly inhibited by the cost of batteries. Research, development, and manufacturing are underway to reduce cost by lowering material costs, enhance process efficiencies, and increase production volumes. Another approach under consideration is to recover a fraction of the battery cost after the battery has been retired from vehicular service via reuse in other applications, where it may still have sufficient performance to meet the requirements of other energy-storage applications.

The increasing role of electronics in automotive systems drives the design of fault tolerant architectures. We envision that tool-based automated analysis of such applications will be increasingly necessary for system designers. In this work, we describe a tool flow to support design space exploration of fault tolerant automotive architectures. Within the flow, we describe and apply a self-designed tool that automatically generates a fault tree from a model of an industrial-sized, safety critical automotive control application. The model represents a deployment containing a set of functions that are mapped to a given set of architecture components. The functions implement data acquisition from sensor devices, perform fault management tasks, compute a control law, and issue commands to the actuators. The architecture component abstractions and modeling artifacts include a set of communication links and electronic control units (ECUs) that are distributed throughout the vehicle.

One of the many challenges facing electronic 1 system architects is how to provide a cost estimate related to design decisions over the entire life-cycle and product line of the architecture. Various cost modeling techniques may be used to perform this estimation. However, the estimation is often done in an ad-hoc manner, based on specific design scenarios or business assumptions. This situation may yield an unfair comparison of architectural alternatives due to the limited scope of the evaluation. A preferred estimation method would involve rigorous cost modeling based on architectural design cost drivers similar to those used in the manufacturing (e.g. process-based technical cost modeling) or in the enterprise software domain (e.g. COCOMO). This paper describes an initial study of a cost model associated with automotive electronic system architecture.

Automotive control applications are implemented over distributed platforms consisting of a number of electronic control units (ECUs) connected by communication buses. During system development, the designer can explore a number of design alternatives: for example, software distribution, software architecture, hardware architecture, and network configuration. Exploring design alternatives efficiently and evaluating them to optimize metrics such as cost, time, resource utilization, and reliability provides an important competitive advantage to OEMs and helps minimize integration risks. We present a methodology (Platform-Based Design) and a framework (Metropolis) to support efficient architecture exploration. We have exercised the methodology and the capabilities of Metropolis for developing a library of automotive architecture components and performed design space exploration on a chassis control sub-system.

Experimental tests were conducted on a Cummins B5.9 direct-injected diesel engine fueled with biodiesel blends. 20% and 50% blend levels were tested, as was 100% (neat) biodiesel. Emissions of particulate matter (PM), nitrogen oxides (NOx), hydrocarbons (HC) and CO were measured under steady-state operating conditions. The effect of biodiesel on total PM emissions was mixed; however, the contribution of the volatile organic fraction to total PM was greater for higher biodiesel blend levels. When only non-volatile PM mass was considered, reductions were observed for the biodiesel blends as well as for neat biodiesel. The biodiesel test fuels increased NOx, while HC and CO emissions were reduced. PM collected on quartz filters during the experimental runs were analyzed for carbon-14 content using accelerator mass spectrometry (AMS).

This research investigates how the handling of mixing and heat transfer in a multi-zone kinetic solver affects the prediction of carbon monoxide and hydrocarbon emissions for simulations of HCCI engine combustion. A detailed kinetics multi-zone model is now more closely coordinated with the KIVA3V computational fluid dynamics code for simulation of the compression and expansion processes. The fluid mechanics is solved with high spatial and temporal resolution (40,000 cells). The chemistry is simulated with high temporal resolution, but low spatial resolution (20 computational zones). This paper presents comparison of simulation results using this enhanced multi-zone model to experimental data from an isooctane HCCI engine.

A multi-zone model has been developed that accurately predicts HCCI combustion and emissions. The multi-zone methodology is based on the observation that turbulence does not play a direct role on HCCI combustion. Instead, chemical kinetics dominates the process, with hotter zones reacting first, and then colder zones reacting in rapid succession. Here, the multi-zone model has been applied to analyze the effect of piston crevice geometry on HCCI combustion and emissions. Three different pistons of varying crevice size were analyzed. Crevice sizes were 0.26, 1.3 and 2.1 mm, while a constant compression ratio was maintained (17:1). The results show that the multi-zone model can predict pressure traces and heat release rates with good accuracy. Combustion efficiency is also predicted with good accuracy for all cases, with a maximum difference of 5% between experimental and numerical results.

Engine fuel tests were conducted with an oxygenated fuel called Cetaner blended with conventional diesel fuel to determine its emissions reduction potential. Blends of 10, 20, 30 and 40% by volume were investigated. The test engine was a 1993 Cummins B5.9 diesel rated at 175 hp. Emissions of particulate matter (PM), oxides of nitrogen (NOx), hydrocarbons (HC) and carbon monoxide (CO), along with brake specific fuel consumption (bsfc) were measured during steady state operation at eight engine speed-load conditions. Soluble organic fraction (SOF) analysis was also carried out on the collected PM filter samples. The experimental results showed that the Cetaner blends can substantially reduce PM emissions. Reductions were observed in both the organic and inorganic fractions of the collected PM. On a modal-averaged basis, increasing Cetaner blend levels yielded greater PM reductions, with reductions of about 3-4% observed for each 1% of oxygen blended to the fuel by mass.

Current trends in technology indicate that nanometer-scale devices will be feasible within two decades. It is likely that NASA will attempt a manned Mars mission within the next few decades. Manned Mars activities will be relatively labor-intensive, presenting significant risk of damage to the Marssuit. We have investigated two possible architectures for nanotechnology applied to the problem of damage during Mars surface activity. Nanorobots can be used to actively repair damaged suit materials while an astronaut is in the field, reducing the need to return immediately to a pressurized area. Assembler nanorobots reproduce both themselves and the more specialized Marssuit Repair Nanorobots (MRN). MRN nanorobots operate as space-filling polyhedra to repair damage to a Marssuit. Both operate with reversible mechanical logic, though only assemblers utilize chemical data storage.

The dynamic stage of combustion - the intrinsic process for pushing the compression polytrope away from the expansion polytrope to generate the indicator work output of a piston engine - was studied to reveal the influence of the air/fuel ratio on the effectiveness with which the fuel was utilized. The results of tests carried out for this purpose, using a 12 liter diesel engine, were reported last year [SAE 1999-01-0517]. Presented here is an analytic interpretation of the data obtained for part-load operation at 1200 and 1800 rpm. A solution is thus provided for an inverse problem: deduction of information on the dynamic features of the exothermic process of combustion from measured pressure record. Provided thereby, in particular, is information on the effectiveness with which fuel was utilized in the course of this process - a parameter reflecting the effect of energy lost by heat transfer to the walls.

The refinement of heat release analysis stems from the recognition that a combustion system is intrinsically non-linear. Thus, as appropriate for such an entity, its properties are expressed in terms of a thermochemical phase (or state) space, of which the thermodynamic aspects are exposed on a so-called Le Chatelier diagram, providing the fundamental background for the development of micro-electronic control to attain the most effective utilization of fuel. Implementation of this method of approach is illustrated by the analysis of the exothermic process taking place in two typical internal combustion engines, spark-ignition and diesel.

1 Attenuation of acoustic noise from automobile components is important for passenger comfort. Since the alternator is one of the major sources of noise, many manufacturers have studied the various mechanisms which generate noise within an alternator as well as the methods to reduce the noise level. This paper presents the dynamic properties of the alternator with respect to the acoustic noise during current generation, and introduces a vibration damping structure based on experimental modal analysis. Rotating magnetic forces in a magnetic circuit (stator and rotor) can excite numerous structural resonances, resulting in acoustic noise. A modal analysis performed on the major magnetic circuit of the alternator (Nippondenso Co., Ltd.) revealed that the stator has elliptic, triangular and rectangular mode shapes in the radial coordinate plane, while the rotor does not have any significant resonances in the same 0 - 3 kHz region.

This paper presents results and analysis of experiments carried out on a vehicle platoon control system developed in the PATH program. The objective of this project is to assess the feasibility of applying currently available technology to the concept of vehicle platoon control. It is estimated that the vehicle platoon system could increase highway traffic capacity by a factor of two or three. The Integrated Platoon Control System (IPCS) includes a control system, communication system, data acquisition system, and various sensors including a radar system. The initial experiments using two Ford cars showed successful results. In the field tests, the automated following vehicle successfully followed the manually driven lead vehicle through several different kinds of maneuvers. This project is a joint effort by U.C.Berkeley, Caltrans and VORAD, with vehicles provided by Ford.

Formation of pulsed plasma jets, or puffs, was examined using several visualization techniques. Self-light streak photography was first employed to record salient global features of the development and structure of the jet. This provided information on the motion of the luminous gas particles in its core, revealing that plasma jets can have two distinct modes, being either totally subsonic or embodying a supersonic efflux manifested by the recorded streaks of Mach discs. At a fixed power pulse of electrical energy discharge in the plenum chamber, the outcome depends on the constriction imposed by an orifice at its outlet. Whereas the difference between the two types of jets was quite small, penetration in the subsonic case was found to be definitely larger than in supersonic.

A single cylinder investigation was conducted to determine concentration of oxides of nitrogen resulting from combustion of ammonia and air in a spark ignition engine over a range of fuel-air ratios typical of normal engine operation with ammonia. Nitric oxide concentrations exceeded that with hydrocarbons. Spectroscopic observations during the expansion process gave concentrations in some instances an order of magnitude greater than exhaust gas determinations. The results imply a different mechanism for nitric oxide formation with ammonia fuel than with hydrocarbons and that some equilibrating process may take place between combustion and exhaust to reduce otherwise even greater than measured exhaust gas concentrations.

This is a continuation of the presentation of thermodynamic properties of selected fuel-air mixtures in chart form, suitable for utilization in engine performance calculations. Methane and propane, representative of natural gas and LPG are the two fuels considered. Using these charts, comparisons are made between the performance to be expected with these gaseous fuels compared to octane, as representative of gasoline. Reduced engine power is predicted and this is confirmed by experience of other investigators.

A theoretical and experimental study was undertaken to establish whether or not parametric correlations could be satisfactorily applied to combustion of ammonia in gas turbine combustors. It was found that a usual parameter of the form I (Re)0.7 was satisfactory for establishing blowout limits in modeling. However, the attainable values of chemical loading I were at least an order of magnitude less than those attainable with hydrocarbon fuels.

Anhydrous ammonia has been demonstrated to operate successfully as a fuel for spark ignition engines. Principal requirements are that it be introduced in the vapor phase and partly decomposed to hydrogen and nitrogen. Spark timing for maximum performance must be advanced slightly for ammonia but sensitivity to spark timing is little greater than with hydrocarbons. Increasing the cylinder wall temperature aids in effecting successful and reliable operation. The maximum theoretically possible indicated output using ammonia vapor is about 77% of that with hydrocarbon. Specific fuel consumption increase twofold at maximum power and 2-1/2 fold at maximum economy when using ammonia as a replacement for hydrocarbon.

Three factors are of consequence when considering the comparative performance of alcohols and hydrocarbons as spark ignition engine fuels. These are: relative amounts of products of combustion produced per unit of inducted charge, energy inducted per unit of charge, and latent heat differences among the fuels. Simple analysis showed significant increases in output can be expected from the use of methyl alcohol as compared to hydrocarbon and somewhat lesser improvement can be expected from ethyl alcohol. Attendant increases in fuel consumption, disproportionate to the power increase, can also be predicted. More sophisticated analysis, based upon thermodynamic charts of combustion products, do not necessarily improve correspondence between prediction and engine results.

A digital computer and special program were used, along with new thermodynamic data, to recalculate and extend the scope and range of the classic combustion gas charts of Hottel and co-workers. A series of hydrocarbon and nonhydrocarbon fuels was treated over a range of fuel-air ratios, with temperatures extended up to 7200 R and pressures up to 15,000 psia. This, the first paper of a series, incorporates the resulting charts for isooctane at four mixture ratios ranging from 20% lean to 40% rich. Auxiliary charts for inducted mixture properties determination and a set of sample calculations are also included.