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Cylinder head combustion chamber and piston temperatures and heat fluxes were measured in a 2.2 L 4 cylinder spark ignition engine. Measurements for the combustion chamber were made at wide open throttle conditions, 1400 rpm to 5000 rpm at 600 rpm increments, additional measurements were made on the combustion chamber at part throttle conditions at 3200 RPM. Piston temperature and heat flux measurements were made at WOT conditions from 1400 to 3200 RPM in 600 RPM increments. Average combustion chamber surface temperatures ranged from 130 deg. C to 248 deg. C, while peak combustion chamber surface temperatures ranged from 142 deg. C to 258 deg. C for WOT conditions. Peak heat flus at the surface for WOT conditions in the combustion chamber ranged from 1.2 MW/m2to 5.0 MW/m2. Central region heat fluxes were 2.3 to 2.8 times greater than those in the end gas regions of the combustion chamber.

Much of the design and development of the modern automobile is dedicated to protecting occupants or reducing vehicle damage during and after a crash. Although the primary function of the vehicle body structure in this respect is to dissipate the kinetic energy of the vehicle, effective protection depends upon careful management of this energy in order to achieve the optimum collapse mechanism. For conventional metal components, the art of creating such “crashworthy” performance is now well understood. However, more and more vehicles are turning to polymer-based composite materials in their structures and these exhibit a totally different type of behaviour in the way that they dissipate energy to the metals which they replace. This paper reviews the fracture mechanisms of these materials, in relation to different impact speeds, as they affect the vehicle designer.

The relationships between air flow metering and combustion control for spark ignition engines, such as engines with three way catalysts, lean NOx catalysts, two stroke engines and direct fuel injection engines were investigated. The effects of control parameters on combustion were analysed and the relationships between control parameters and air flow metering and roles of the meters in combustion control were clarified. The control strategies adaptable to many types of engines which have a wide control range of the air/fuel mass ratio are classified as (1) air quantity control,(2) fuel quantity control, and (3) exhaust gas recycle quantity control. The control parameters for the three strategies are fuel quantity, air quantity, exhaust gas recycle quantity, exhaust gas temperature, knocking, excess air factor, and mixture quality with additional parameters of swirl ratio, and spark timing for conventional spark ignition engines, two stroke engines and direct injection engines.

Postcrash fires are a frequent cause of death in otherwise survivable automobile and aircraft accidents. The idea of the ICED (Internal Circuit Emergency Disconnect) battery [1] is to eliminate electrically ignited postcrash fires by means of an inertial interrupt device that will disconnect the active circuit at the battery if an accident should happen. The design of the prototypes that were tested and the analysis of the disengagement performance will be discussed. A ballistic pendulum impact test rig was designed and used to test the prototypes. The test results and analytical values were shown to be satisfactorily close to each other.

Automotive vehicle crash safety requirements have steadily become more stringent over the last decade. Automobiles of tomorrow have to comply with a host of requirements in various crash modes in order to be considered roadworthy. In the first section of the paper, the current major requirements, some important requirements that are imminent, and desirable requirements in the near future are briefly discussed. Until recently, crash requirements have been focused mostly on the vehicle structure rather than the occupant protection, with the exception of frontal crash. Scarcity of in-depth interpretation of accident data, lack of biofidelic injury assessment devices (“crash dummies”) and the necessity for test repeatability had kept the testing procedures simple. Often, crash testing involved statically loading the vehicle to measure the structural strength, without consideration of the dynamic behavior of the structure or the structure/occupant interaction.

Demonstration projects of many Diesel Particulate Traps have been and continue to be performed. Many experimental trap systems require software customization to an individual vehicle to account for duty cycle and component variations. This level of customization is not practical in a production environment and in a marketplace where a trap system needs to function on many types of engines and duty cycles. This paper describes the production experience of the Donaldson Dual Ceramic Wall Flow Electric Regeneration Diesel Particulate Trap which has overcome specific production and durability obstacles.

Lifetimes of DPF under various thermal stress cycles were calculated based on the slow crack growth theory and expected lifetimes were investigated in relation to maximum temperature during regenerations. The fatigue characteristics of porous honeycomb structures follow the slow crack growth theory. Maximum thermal stress was calculated from temperature distributions of failed DPF. The ratio of 4-point bending strength to maximum thermal stress was used as a correction factor. The thermal stress was calculated from various temperature distributions and then modified with the correction factor. These results were compared with the fatigue characteristics obtained from 4-point bending fatigue tests.

Progress made in reducing engine-out particulate emissions has prompted a revival in the design of flow-through oxidation catalysts for diesel engine applications. Effort in this area has focused primarily in the area of SOF control for the further reduction of particulate emissions. The work reported here covers some of the catalyst design parameters important for SOF and gas phase pollutant control. This is illustrated with both laboratory reactor and engine evaluation data for several formulary and operating parameters. Platinum-based catalysts are shown to be generally the most active, but they require treatments or additives to reduce the inherently high activity of platinum for the oxidation of SO2 present in the exhaust. The effect of additives and their loading on the oxidation activity of Pt/alumina for HC, CO, SOF and SO2 oxidation is discussed in detail and additives are identified which reduce SO2 oxidation with minimal effect on HC, CO or SOF oxidation activity.

Catalytic converters have become a viable aftertreatment system for reducing emissions from on-highway diesel engines. This paper addresses the development and production qualification of a catalytic converter. The testing programs that were utilized to qualify the converter system for production included emissions performance, emissions durability, physical durability, and field test programs. This paper reports on the specific tests that were utilized for the emissions performance and emissions durability testing programs. An explanation on the development of an accelerated durability test program is also included. The physical durability section of the paper discusses the development and execution of laboratory bench tests to insure the catalytic converter/muffler maintains acceptable physical integrity.

A Method for determining the actual initiation of the SOF oxidation temperature has been needed for accurate evaluation of the performance of a diesel oxidation catalyst. Since SOF is absorbed by the catalyst, its oxidation temperature is difficult to determine by analyzing emissions from an engine. In this study, the following thermal analysis methods were used: Thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC). A small piece of monolithic catalyst was used to absorb the SOF extracted from the particulate filter. The SOF oxidation characteristics of catalysts were evaluated using these thermal analysis methods. From these analysis, the order of activation of each catalyst was determined with the inflection points in TG curves and the DTA and DSC peak points indicate the catalytic characteristics. The thermal analysis methods have been found to be effective in evaluating the performance of catalysts.

An earlier study (SAE Paper 920364) documented the ability of a Copper-based fuel additive to initiate regeneration of a particulate trap without external heat sources. Work performed with Southeastern Pennsylvania Transit Authority on diesel particulate filter systems for a 6V-92TA mechanical engine has been expanded to include 6V-92TA electronic, MAN and Caterpillar engines as well as an increased number of 6V-92TA mechanical engines. Both cordierite wall flow and fibre filter systems are currently being evaluated for performance and durability in field service. This paper outlines performance of the system which uses a copper-based fuel additive to induce regeneration along with emission reductions and health effects data. Additional data on compatibility of the copper fuel additive with typical commercial diesel fuels and lubricants is also presented.

Recently, 3000 catalytic purifiers have been sold into Santiago, Chile, for use on urban buses. The sale into Santiago resulted from over two years of demonstrating the performance of diesel catalytic purifiers in various Latin American countries. This paper highlights the results of the demonstrations including a variety of engine-types, opacity reductions provided by the use of purifiers, preliminary durability data and the present status of the use of catalytic technology in Latin America.

Fuel economy measurements from portions of Phase I of the Auto/Oil Air Quality Improvement Research Program were analyzed. The following fuel variables were examined: aromatics, olefins, T90, RVP, and various oxygenates (MTBE, ETBE and ethanol). Two vehicle fleets were tested: twenty 1989 vehicles and fourteen 1983-1985 vehicles. Three measures of fuel economy were analyzed. EPA Fuel Economy used the calculation defined in the Federal Register and is an attempt to correct for changes in fuel properties. Volumetric Fuel Economy is based on a carbon balance calculation and is a measure of the actual volume of gasoline burned. Energy Specific Fuel Economy is a measure of fuel economy based on energy content. The following fuel changes resulted in reductions of Volumetric Fuel Economy in both fleets: reduced aromatics, reduced olefins, reduced T90, and addition of oxygenates. Changes in RVP did not have a significant effect on fuel economy.

A proportional sampler for vehicle feedgas and tailpipe emissions has been developed that extracts a small, constant fraction of the total exhaust flow during rapid transient changes in engine speed. Heated sampling lines are used to extract samples either before or after the catalytic converter. Instantaneous exhaust mass flow is measured by subtracting the CVS dilution air volume from the total CVS volume. This parameter is used to maintain a constant dilution ratio and proportional sample. The exhaust sample is diluted with high-purity air or nitrogen and is delivered into Tedlar sample bags. These transient test cycle weighted feedgas samples can be collected for subsequent analysis of hydrocarbons and oxygenated hydrocarbon species. This “mini-diluter” offers significant advantages over the conventional CVS system. The concentration of the samples are higher than those collected from the current CVS system because the dilution ratio can be optimized depending on the fuel.

Catalytic reduction of NOx from diesel engine exhaust by the addition of saturated hydrocarbons, or diesel fuel has been demonstrated using a newly developed copper containing catalyst system. Fundamental interactions between NOx, oxygen and hydrocarbons over the copper based catalysts have been studied in relation to NOx reduction by hydrocarbon additions and in relation to hydrocarbon oxidation. The different NOx reduction characteristics of the various hydrocarbons, were revealed. Based on this work, the catalyst system and the hydrocarbon spray system have been designed to effectively reduce NOx over a wide exhaust temperature range. In laboratory experiments, the newly developed catalyst system combined with a diesel fuel or heavy saturated hydrocarbon spray system effectively reduces NOx by 20%-30% over an exhaust temperature range of 350°C - 550°C.

Fuel effects on exhaust emissions of a sample of seven high emitting vehicles were studied. The vehicles had various mechanical problems and all ran fuel rich. The degree of enrichment varied between tests, and strongly affected mass emissions. Variable enrichment can cause incorrect apparent fuel effects to be calculated if not accounted for in data analysis. After variable enrichment was compensated for, the percentage effects of fuel oxygen, RVP, and olefins were largely in agreement with prior findings for normally emitting vehicles. Reducing fuel sulfur and T90 may have less benefit on hydrocarbon emissions in these high emitters than in normal emitters, and reducing sulfur may have less benefit on CO emissions. Reducing aromatics may be somewhat more helpful in reducing hydrocarbon and CO emissions in the high emitters.

The objective of this study was to determine the effects of vehicle front end components on engine compartment air flow. Isothermal road tests were conducted on a 1989, four door sedan car having a 3.0 liter V-6 engine and an automatic transmission. The vehicle under study had a combined grille area of 0.1194 square meters. The engine occupied approximately 35% of the under hood plan view area. The air velocities measured at the radiator exit section (between the radiator and the fan shroud) were the data of interest. No coolant was circulating in the OE radiator or heater core, and no refrigerant was flowing in the OE condenser or evaporator. However, constant air temperature runs were accomplished by having a remote radiator installed at the rear of the vehicle for engine cooling during the tests.

This paper is the third in a series providing fuel blending and analysis data for the Auto/Oil Air Quality Improvement Research Program (AQIRP). Preparation methodologies, analytical techniques and fuel property data are presented for the Heavy Hydrocarbon/Volatility study and other programs not previously reported. Papers by Pahl and McNally (1)* and Gerry et al. (2) have presented information on the fuels of the AMOT (Aromatics, MTBE, Olefins, T90), Methanol, RVP/Oxygenate and Phase I and II Sulfur programs. The Heavy Hydrocarbon/Volatility fuel study was initiated in an effort to better understand the 90% distillation point (T90) effect observed in the AMOT matrix of Phase I. The study was comprised of two matrices and twenty-six fuels. The first eighteen-fuel matrix, designated as the “A” matrix, investigated the effects of medium, heavy and tail reformate and medium and heavy catalytically cracked components.

Filter regeneration systems require an accurate and reliable measurement of diesel particulate (soot) accumulation. This paper describes recent advances in the development of a device that uses radio-frequency (RF) technology to measure filter soot loads. A one-point calibration method is presented that provides a means to significantly reduce filter system development costs. Results from both on-vehicle and laboratory testing programs are discussed. The on-line monitoring of catalytic and energy-addition regeneration processes is also described.

Primary measures, to reduce the NOx emissions from diesel engines, penalize the fuel consumption and aggravate the CO2 problem. Instead, an after-treatment system is proposed that permits optimum combustion and yet reduces the NOx by more than 95%. Such installations are in operation for more than five years. Successful deployment on a short-haul ferry, subject to highly cyclic operation, began in Spring 1992. The chief features are high space-velocity (25,000 1/h), urea as non-toxic reactant and rapid transient response. The attained results counter the misgivings about the SCR catalysis. Development aims at further halving the size thus facilitating service in off-highway vehicles such as locomotives and earth-movers. The integration of particulate traps using knitted micro-fibers is under development.