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Polyacrylate elastomers are currently manufactured by polymer suppliers in Italy, Japan and United States to fulfil oil resistance requirement of automotive industry. However aging conditions have significantly changed over the years so that updated experimental results are demanded by industry along with new generation products showing enhanced properties. As an example, no-post cure polyacrylic rubbers are today available to satisfy their users' processablity concerns.

We studied new-type heat-resistanct elastomers. They are based on fluoroelastomer/ acrylic-elastomer blands. Their heat resistance temperature for long term use are about 175°C. They are graded E to F class for heat resistance and G to H class for oil resistance within the ASTM D2000/SAE J200 framework. In this presentation, newly developed elastomers are discussed.

Many foams exhibit significant strain rate dependency in their mechanical responses. To characterize these foams, a strain rate dependent constitutive model is formulated and implemented in an explicit dynamic finite element code developed at FORD. The constitutive model is developed in conjunction with a Lagrangian eight node solid element with twenty four degrees of freedom. The constitutive model has been used to model foams in a number crash analysis problems. Results obtained from the analyses are compared to the experimental data. Evidently, numerical results show excellent agreement with the experimental data.

The New U.S. Evaporative Emission Regulations, which set forth the level of hydrocarbon evaporation generated from vehicles, have been applied in the industry since 1994. In order to meet the Regulations, the filler hose is required to be made for a one tenth of the gasoline permeability of that for conventional filler hose, without design change. The fuel filler hose must also provide a flexible configuration, such as a bellowed or a complicatedly curved shape In order to cope with the problems above, the Author, et al, have successfully developed A LOW PERMEATION FUEL FILLER HOSE which has a high freedom of configuration. During the first stage of development, the Author, et al, developed a hose of 2-layer structure using FKM rubber for inner layer as the permeation barrier, which is applicable in the bellow shape, by means of a unique molding technique.

The new vehicle generations will have electronic architectures much more complex than we thought some years ago. This presentation should give a status and an outline of future electronic solutions in powertrain control.

The development, evaluation, and selection of Plasma spray powder material for the coating of aluminum-alloy engine cylinder block bores was conducted to yield a bore system which provides numerous benefits relative to the present cast iron sleeve system. These include: a reduction in ring/bore wear, friction, and in engine oil consumption as well as a benefit in reduced corrosion. A reduction in engine weight, overall costs, and improvements in machining and honing operations are shown. Alternate thermal spray processes are also described in this investigation. Test evaluation leads to the selection of two plasma powder material spray systems. One system emphasizes low cost relative to the present system. The second system provides significant reduction in friction and ring/bore wear through the introduction of solid lubricant in the material composition.

Transient operation of automobile engines is known to contribute significantly to regulated exhaust emissions, and is also an area of drivability concerns. Furthermore, many on-board diagnostic algorithms do not perform well during transient operation and are often temporarily disabled to avoid problems. The inability to quickly and repeatedly test engines during transient conditions in a laboratory setting limits researchers and development engineers ability to produce more effective and robust algorithms to lower vehicle emissions. To meet this need, members of the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison have developed a high-bandwidth, hydrostatic dynamometer system that will enable researchers to explore transient characteristics of engines and powertrains in the laboratory.

In closed evaporation control systems, the purging air flow through the active carbon canister is mixed with the intake air flow. In order to avoid degradation of the λ control and the pollution emission levels, the purged hydrocarbons must be evenly distributed among the cylinders and mixed as thoroughly as possible with the intake air. Based on the purge charactisctics of standard carbon canisters and on the HC levels in a fully charged carbon canister, and using a 4-cylinder sixteen-valve engine, the operating frequency of the canister purge valve and the inlet point of the purge flow into the intake manifold were varied, using n-butane as the hydrocarbon. The measurements taken for HC emissions and the voltages of the lambda probes in the exhaust manifold showed that the inlet point, the valve operating frequency and the microdosing behavior of the valve significantly affect mixture and engine's HC emissions.

An extremely tough alumina based ceramic coating produced by a modified anodizing process developed at Moscow Aviation Institute has been evaluated for light weight, wear resistant component applications in automotive powertrain. The process details and test results from comparative evaluation of friction and wear properties for cylinder bore application, referenced to cast iron baseline, are presented and discussed.

A commercial DOHC 4-Cylinder sequential MPI SI engine was modified as a research single cylinder engine. And four kinds of cylinder head with the same combustion chamber geometry have been used to induce in-cylinder flow of different swirl ratio. To investigate the effect of injection timing on the lean misfire limit (LML), experiments have been made at selected engine speeds for each cylinder head. Fuel injection timing was varied while running the engine at a constant speed. And the LML was defined as the mixture ratio at which engine speed deviates more than 10 rpm from the present speed resulting in the engine instability which might be causing from misfire or partial combustion. Results show that LML or stability of engine is not affected by engine speed because early flame stability is dominated not by turbulence but by AFR around the spark plug at spark timing. Stratification of mixture resulting from port swirl and injection timing were shown to govern the LML.

In this paper, we present simulation results for a variety of linear control design techniques, for simplified models of a GM V6 3800 IC engine. Control objectives focus on smooth engine operation at idle speeds, under significant accessory load disturbances, using air and spark as the primary control variables. A different feature of this work is that the engine modeling problem is approached from the crank angle domain; that is, the models for control design are based on the crank angle as the independent variable, as opposed to more typical representations set in the time domain. The models developed are based on first principles as well as on identification results from available data.

This paper presents a method of balancing the cylinder to cylinder torque fluctuation of an idling engine by controlling the individual spark timing. This method has the capability to compensate for individual fuel/air imbalance that might occur for example due to miscalibration of a fuel injector. The method is based upon noncontacting crankshaft angular speed flucuations and upon a control system that regulates individual spark timing in response to imbalance in that speed variation. The theory of the method is explained and experimental verification of the method is presented for a 4 cylinder engine.

In this paper, we propose an IC engine fuel system diagnostic algorithm based on a discrete-event nonlinear observer using the production oxygen sensor. A mean value engine model is used to describe the engine dynamics. A procedure for designing the discrete event based observer is presented and applied to estimate important engine variables using the measured binary oxygen sensor output. The estimated variables are then used to perform diagnostics of the fuel system of the IC engine. Experimental results on a multi-cylinder production engine are presented to demonstrate the effectiveness of the proposed method.

The process of incorporating the spark plug as a combustion probe, to perform misfire and knock detection, air to fuel ratio and spark timing control has been the subject of research for some time now. [3], [4]. The feasibility of the approach however depends on being able to correlate some characteristic of the ion current signal to the in cylinder combustion process. Shimaski et al. [3] and Miyata et al. [4] suggest such a relationship. The objective of this research has been to extract combustion information from the measured ion current flowing between spark plug electrodes by using various advanced signal processing methods, and to develop a methodology that will permit combustion diagnostics and possibly control based on these measurements. Tests were carried out on a single-cylinder, methane-fueled CFR engine.

An in-vehicle detecting apparatus has been developed which detects an ion current to monitor the combustion condition of each cylinder of the spark ignition internal combustion engine. This apparatus uses the spark plug electrode as an ion probe, and applies, as bias power, a very low ignition energy accumulated in the ignition coil. Thus it has the feature of requiring no particular modification on the engine side except a minor revision of the ignition system and addition of a detection module. This paper presents the construction and operation of this detection apparatus; in-engine evaluation and consideration on misfire and knocking level detecting performance; and consideration on effects of various factors on ion current values detected. In addition, data on the possibility of detecting an air-fuel ratio is reported.

This paper addresses issues associated with the accurate determination of absolute cylinder pressure in internal combustion engines. Pressure referencing errors are shown to produce large errors in derived parameters such as polytropic index, mass fraction burned and charge temperature. Two alternative pressure correction methods, namely inlet manifold pressure and polytropic index referencing are investigated in detail. Sources of errors and algorithm improvements are investigated and discussed. Comparison between the two pressure referencing techniques is made using measured cylinder pressure data obtained from a gasoline engine operating over a wide range of speeds and loads. The analysis shows that both of the methods should be capable of referencing typical experimental pressure data to within +-100 mbar. The work has demonstrated that accurate absolute pressure referencing can only be achieved if common pressure measurement errors are minimised.

This paper describes a model for EGR mass flow rate estimation as a function of signal smeasured by existing sensors in an internal combustion electronically controlled engine. An original approach is presented to take into account the heat transfer between the EGR duct and the environment. The preliminary results relative to EGR mass flow rate estimation suggest that the methodology may be extended towards the development of a complete model of the intake manifold including the EGR recirculation system and the purge canister.

This paper addresses issues associated with the accurate determination of mass fraction burned (MFB) in gasoline engines. Items covered include an evaluation of the accuracy of alternative MFB models and the effects of errors in the absolute pressure referencing, crank angle phasing and assigned compression ratio. The implications of using crank angle averaged pressure data and varying the crank angle resolution and number of engine cycles are also covered. The well known Rassweiler and Withrow MFB model was found to produce the best results in comparative tests with simulated and experimental pressure data. Absolute pressure referencing offset caused the largest error in the calculated MFB and burn angles, particularly at low engine load. Calculated data at the extreme ends of the MFB curve were shown to be most sensitive to measurement errors and noise.

Engine designers need an objective measurement which can be tested on the engine to indicate acceptable idle quality. An experiment was performed to select objective measures based on cylinder pressure data, and two measures were selected. Standard deviation of indicated mean effective pressure (SDimep) is a measure of the statistical instability of combustion. Lowest normalized value (LNV) is a measure of the tendency toward misfire. These two measures are shown for a set of typical engines. The body of data shows the relation of SDimep and LNV to burn duration and timing.

An automatic failure diagnosis system for engines where we apply motoring test bed and sampled firing test set is proposed in this paper. Focusing on the inspection items where sound signals can be employed, we propose a new approach utilizing wavelet transform, FFT analysis and cepstrum analysis to anomaly characterization. For three important items, namely tappet clicks, misfire and mismatching, the following results have been obtained. (1) For tappet clicks, motoring test is more effective than firing test in recognizing the features of the anomaly. Wavelet transform is more reliable and convenient than FFT analysis to extract the features. (2) For misfire, cepstrum analysis is simple and effective to detect the features. (3) For abnormal combustion sound due to time mismatching, FFT analysis can be applied to extract the features. Further studies are required for finding more effective methods.