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Technical Paper

Oxygenates screening for AdvancedPetroleum-Based Diesel Fuels: Part 2. The Effect of Oxygenate Blending Compounds on Exhaust Emissions

Adding oxygenates to diesel fuel has shown the potential for reducing particulate (PM) emissions in the exhaust. The objective of this study was to select the most promising oxygenate compounds as blending components in diesel fuel for advanced engine testing. A fuel matrix was designed to consider the effect of molecular structure and boiling point on the ability of oxygenates to reduce engine-out exhaust emissions from a modern diesel engine. Nine test fuels including a low-sulfur (∼1 ppm), low-aromatic hydrocracked base fuel and 8 oxygenate-base fuel blends were utilized. All oxygenated fuels were formulated to contain 7% wt. of oxygen. A DaimlerChrysler OM611 CIDI engine for light-duty vehicles was controlled with a SwRI Rapid Prototyping Electronic Control System. The base fuel was evaluated in four speed-load modes and oxygenated blends only in one mode. Each operating mode and fuel combination was run in triplicate.
Technical Paper

The Influence of Residual Stresses on the Susceptibility to Hydrogen Embrittlement in Hardened Steel Components Subjected to Rolling Contact Conditions

A review of many years of published work has shown that hydrogen embrittlement can occur under rolling contact conditions. Breakdown of lubrication and contamination with water have been cited as the probable sources of atomic hydrogen. In this paper, a unique fracture morphology is identified and the mechanism of the fracture progression from initiation to final catastrophic failure is proposed. Development of beneficial residual compressive stress near the contacting surfaces is one approach used to avoid this type of failure. Several alternative methods capable of developing a more desirable stress distribution will be discussed.
Technical Paper

Urban Air Quality Improvements by Means of Vehicular Diesel Particle Filters

The project objective was to investigate the ultrafine solid particle emissions of the prevalent traffic, by performing field measurements at an urban traffic artery in Zurich/Switzerland. Subsequently, various scenarios were postulated to assess the potential of the diesel particle filters (DPF) to improve curbside air quality. Soot aerosols are known to be carcinogenic [1]. If all heavy-duty diesel vehicles were equipped with DPFs, then the number of particles emitted from the entire vehicle fleet could be reduced by 75 to 80%. For PM10, the curtailment scope is considerably lower, around 20%, because more than half of those emissions are not from the exhaust and therefore would not be filtered.
Technical Paper

Rolling Bearings for High Performance Hydrostatic Drives Using Water Glycol Based Hydraulic Fluids

Hydraulic fluids of the HFC category are aqueous polymer solutions with a fire resistance enhancing water content of 35 to approx. 50 %. The use of HFC fluids, above all in mobile and stationary drives in mining and in casting is subject to restrictions resulting from a number of features of a fluid. Field practice has shown that while axial-piston pumps may be successfully operated using HFC fluids, rolling bearing failures reduce their operational lifetimes. The bearing failures essentially result from material fatigue. This can be remedied by new quality steel for roller bearings. The combination of high fatigue life and corrosion resistance assures a wide application range for nitrogen-treated steel qualities.
Technical Paper

Interpreting Remote Sensing NOx Measurements: at Low Load near Chicago 1997-1999, and at High and Low Load Sites on the Same Ramp in Phoenix, 1999

Remote sensing nitric oxide (NO) measurements are difficult to analyze because load varies among on-road vehicles measured by remote sensing and NO emissions are dependent on load. Remote sensing NO measurements were made on passenger cars in 1997, 1998, and 1999 in Chicago, IL at a site where few vehicles had loads greater than those encountered in the FTP. Passenger car NO emissions could be modeled by an equation with an age term and a load term for measurements made under moderate load. Onset of decreasing NO emissions with increasing load was observed to occur at lower load for older technology vehicles. Light duty vehicles were measured by remote sensing at two sites on the same ramp in Phoenix, AZ. A large proportion of the vehicles at one of the sites was under loads far in excess of those experienced in the FTP. NO could not be characterized by a single valued function of age and load for both Phoenix sites even though the fleet at the two sites was very similar.
Technical Paper

Effects of Section Size and Microstructural Features on the Mechanical Properties of Die Cast AZ91D and AM60B Magnesium Alloy Test Bars

Reported tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys indicate that those values depend on the size and shape of the test samples and their global porosities. This paper reviews the mechanical properties reported in the open literature for these die cast alloys and indicates that section thickness and global porosity are inadequate for predicting the tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys.
Technical Paper

Microstructural Characteristics of Die Cast AZ91D and AM60 Magnesium Alloys

Die cast AZ91D and AM60 magnesium alloy components are finding increasing usage in automotive applications. Both hot and cold chamber die cast components of these alloys generally exhibit several common microstructural features, including “skin”, porosity banding, and porosity distributed about the component centerline. Methods for quantitatively characterizing these microstructural features are described and representative values for skin thicknesses, porosity band dimensions and porosity band locations from selected die castings will be presented. The expected influence of these common microstrucutral features on mechanical properties and acceptability of die cast magnesium components for given applications are discussed.
Technical Paper

Fatigue Properties of Die Cast Magnesium Alloys

This paper provides a review of the fatigue properties reported in the open literature for die cast magnesium-based alloys. Recently developed fatigue data, in the form of stress versus number of cycles to failure for bending fatigue (R=-1), are presented for die cast AM60B and AZ91D alloy specimens with thicknesses between 1 and 10 mm. The effects of specimen thickness and macrostructural features, such as porosity distributions and surface features (parting line and ejection pin marks), on the fatigue data are discussed.
Technical Paper

Advanced Power Sources for a New Generation of Vehicles

The U.S. Department of Energy (DOE) and the U.S. automotive industry are collaborating on research and development of advanced compression ignition direct injection (CIDI) engine technology and polymer electrolyte membrane (PEM) fuel cells for automotive applications. Under the auspices of the Partnership for a New Generation of Vehicles (PNGV), the partners are developing technologies to power an automobile that can achieve up to 80 miles per gallon (mpg), while meeting customer needs and all safety and emissions requirements. Research on enabling technologies for CIDI engines is focusing on advanced emissions control to meet the proposed stringent Environmental Protection Agency emissions standards for oxides of nitrogen (NOx) and particulate matter (PM) in 2004, while retaining the high efficiency and other traditional advantages of CIDI engines.
Technical Paper

CRC Carbonyl Emissions Analysis Round Robin Program - Phase II

A second carbonyl round robin was conducted to enable participating laboratories doing routine analysis of carbonyls in vehicle exhaust emissions to assess their analytical capabilities. Three sets of solutions in acetonitrile containing varying number and amounts of standard DNPH-carbonyls were prepared. The parent carbonyls are known components of vehicle exhaust emissions. The samples were designed to challenge the capabilities of the participants to separate, identify and quantify all the components. The fourteen participating laboratories included automotive, contract, petroleum and regulatory organizations. All participants were able to separate and identify the C3 carbonyls; a few were not able to separate MEK from butyraldehyde and methacrolein from butyraldehyde; and many were not able to separate adequately the isomers of tolualdehyde. Inadequate separation and lack of appropriate standards resulted in a few misidentifications.
Technical Paper

Reduction of Exhaust Emission from a Stoichiometric Engine Using Non-Thermal Plasma Generated by a Corona Discharge Device

A corona discharge device (CDD) used in conjunction with automotive stoichiometric catalysts has been shown to be effective in reducing exhaust tailpipe emissions and catalytic converter light-off temperatures. The CDD used here is a low power, low cost corona discharge device mounted ahead of the catalytic converter in the exhaust stream. Creation of radicals and other oxidizing species in the exhaust by the non-thermal plasma is shown to significantly improve catalyst conversion efficiencies for HC, CO and NOx. Burner flow data shows improvement in steady-state conversion efficiencies as well as improved catalyst light-off performance. Engine-dynamometer and vehicle data on spark ignition engines using production type (stoichiometric) control also shows improved performance with aged catalysts, and various levels of fuel sulfur. The reversibility of sulfur poisoning was also observed.
Journal Article

Brake Dynamometer Test Variability Part 2- Description of the Influencing Factors

The ISO TC22/SWG2 - Brake Lining Committee established a task force to determine and analyze root causes for variability during dynamometer brake performance testing. SAE paper 2010-01-1697 “Brake Dynamometer Test Variability - Analysis of Root Causes” [1] presents the findings from the phases 1 and 2 of the “Test Variability Project.” The task force was created to address the issue of test variability and to establish possible ways to improve test-to-test and lab-to-lab correlation. This paper presents the findings from phase 3 of this effort-description of factors influencing test variability based on DOE study. This phase concentrated on both qualitative and quantitative description of the factors influencing friction coefficient measurements during dynamometer testing.
Journal Article

Influence of Test Procedure on Friction Behavior and its Repeatability in Dynamometer Brake Performance Testing

The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.
Technical Paper

Brake Dynamometer Test Variability - Analysis of Root Causes

Modern project management including brake testing includes the exchange of reliable results from different sources and different locations. The ISO TC22/SWG2-Brake Lining Committee established a task force led by Ford Motor Co. to determine and analyze root causes for variability during dynamometer brake performance testing. The overall goal was to provide guidelines on how to reduce variability and how to improve correlation between dynamometer and vehicle test results. This collaborative accuracy study used the ISO 26867 Friction behavior assessment for automotive brake systems. Future efforts of the ISO task force will address NVH and vehicle-level tests. This paper corresponds to the first two phases of the project regarding performance brake dynamometer testing and presents results, findings and conclusions regarding repeatability (within-lab) and reproducibility (between-labs) from different laboratories and different brake dynamometers.
Technical Paper

Effect of an Oxidation Catalyst on Exhaust Emissions of a DI Diesel Engine Operating with Fumigation of the Intake Air with Superheated Steam

An oxidation catalyst was fitted on a DI diesel engine for an experimental study involving an oxidation catalyst and the use of superheated steam for fumigating the intake air. Results are compared with that of the influence of low level of fumigation of the intake air with superheated diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. The technique used an electric vaporizer for producing superheated steam and prevaporised superheated diesel fumes at 350 °C, respectively. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.
Technical Paper

Effect of an Oxidation Catalyst on Exhaust Emissions of a DI Diesel Engine Operating with a Partial Fumigation of the Intake Air with Fuel

Results showed the influence of the oxidation catalyst on exhaust emissions from a DI diesel engine due to the partial premixing, fumigation of the intake air with diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. Two methods of diesel fumigation of the intake air with fuel were used. The difference between these two methods was the degree of premixing of diesel fuel with the intake air. The first technique used a high-pressure fine diesel spray onto a glow plug and the second technique used an electric vaporizer for prevaporised superheated diesel fumes at 350 °C. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.
Technical Paper

NOx Reduction Kinetics Mechanisms and Radical-Induced Autoignition Potential of EGR in I.C. Engines Using Methanol and Hydrogen

This numerical study examines the chemical-kinetics mechanism responsible for EGR NOx reduction in standard engines. Also, it investigates the feasibility of using EGR alone in hydrogen-air and methanol-air combustion to help generate and retain the same radicals previously found to be responsible for the inducement of the autoignition (in such mixtures) in IC engines with the SONEX Combustion System (SCS) piston micro-chamber. The analysis is based on a detailed chemical kinetics mechanism (for each fuel) that includes NOx production. The mechanism for H-air-NOx combustion makes use of 19 species and 58 reactions while the methanol-air-NOx mechanism is based on the use of 49 species and 227 reactions. It was earlier postulated that the combination of thermal control and charge dilution provided by the EGR produces an alteration in the combustion mechanisms (for both the hydrogen and methanol cases) that lowers peak cycle temperatures-thus greatly reducing the production of NOx.
Technical Paper

The Benefits and Costs of Diesel Particulate Control III-The Urban Bus

This study applies the methodology developed for two earlier evaluations of diesel particulate controls to urban buses. Since these vehicles are used almost exclusively in urban areas where population is most dense, the analysis indicates the net benefits of control are very high.
Technical Paper

Comparison of CVT Engine Operating Schedules

Maximum fuel economy and Low exhaust emissions can exist together if a predominantly wide-open-throttle engine operating schedule is used to complement a continuously variable transmission. Moreover, the concurrently required engine re-calibration often entails less effort than the more usual fuel consumption and emission mapping procedure.
Technical Paper

Analytic Process to Develop a Local Truck Driving Cycle

Driving cycles have been used in Federal Test Procedures to establish fuel economy and emissions characteristics for automobiles. Reasonable driving cycles for trucks and buses have been more difficult to establish because of the great variety of uses which these vehicles experience. The truck cycle has been divided into three different use categories—the local cycle, the short haul cycle, and the highway cycle. Only recently, has actual field data been obtained, and this paper proposes a method of utilizing this data to develop a more realistic local cycle than those previously proposed.