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Active regeneration systems for cleaning diesel exhaust can operate at extremely high temperatures up to 1000°C. The extremely high temperatures create a unique challenge for the design of regeneration structural components near their melting temperatures. In this paper, the preparation of the sheet specimens and the test set-up based on induction heating for sheet specimens are first presented. Tensile test data at room temperature, 500, 700, 900 and 1100°C are then presented. The yield strength and tensile strength were observed to decrease with decreasing strain rate in tests conducted at 900 and 1100°C but no strain rate dependence was observed in the elastic properties for tests conducted below 900°C. The stress-life relations for under cyclic loading at 700 and 1100°C with and without hold time are then investigated. The fatigue test data show that the hold time at the maximum stress strongly affects the stress-life relation at high temperatures.

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.

A task group within the SAE Automotive Corrosion and Protection (ACAP) Committee continues to pursue the goal of establishing a standard test method for in-laboratory cosmetic corrosion evaluations of finished aluminum auto body panels. The program is a cooperative effort with OEM, supplier, and consultant participation and is supported in part by USAMP (AMD 309) and the U.S. Department of Energy. Numerous laboratory corrosion test environments have been used to evaluate the performance of painted aluminum closure panels, but correlations between laboratory test results and in-service performance have not been established. The primary objective of this project is to identify an accelerated laboratory test method that correlates with in-service performance. In this paper the type, extent, and chemical nature of cosmetic corrosion observed in the on-vehicle exposures are compared with those from some of the commonly used laboratory tests

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.

Two-stroke gasoline engines are known to benefit from using in-cylinder fuel injection which improves their ability to meet the strict fuel economy and exhaust emissions requirements. A conventional method of in-cylinder fuel injection involves application of plunger-type positive displacement pumps. Two-stroke engines are usually smaller and lighter than their 4-stroke counterparts of equal power and need a pump that should also be small and light and, preferably, simple in construction. Because a 2-stroke engine fires every crankshaft revolution, its fuel injection pump must run at crankshaft speed (twice the speed of a 4-stroke engine pump). An electronically controlled fuel injection system has been designed to satisfy the needs of a small automotive 2-stroke engine capable of running at speeds of up to 6000 rpm.

A highly controlled six-vehicle crash test program was conducted to provide an estimate of the test-to-test variability of the NHTSA-proposed passenger car dynamic side impact test procedure. The results of this program showed that the rear seat test dummy response measurements are especially sensitive to various parameters of the test procedure. This paper provides estimates of front and rear seated SID dummy response measurement variability in four-door, 1990 Ford Taurus vehicles. Conclusions and recommendations from this controlled crash test program are made to provide guidance to help reduce the test-to-test variability of the test dummy responses.

Current CJ-4 lubricant specifications place chemical limits on diesel engine oil formulations to minimize the accumulation of lubricant-derived ash in diesel particulate filters (DPF). While lubricant additive chemistry plays a strong role in determining the amount and type of ash accumulated in the DPF, a number of additional factors play important roles as well. Relative to soot particles, whose residence time in the DPF is short-lived, ash particles remain in the filter for a significant fraction of the filter's useful life. While it is well-known that the properties (packing density, porosity, permeability) of soot deposits are primarily controlled by the local exhaust conditions at the time of particle deposition in the DPF, the cumulative operating history of the filter plays a much stronger role in controlling the properties and distribution of the accumulated ash.

Over the past several years a task group within the SAE Automotive Corrosion and Protection (ACAP) Committee has conducted extensive on-vehicle field testing and numerous accelerated lab tests with the goal of establishing a standard accelerated test method for cosmetic corrosion evaluations of finished aluminum auto body panels. This project has been a cooperative effort with OEM, supplier, and consultant participation and was also supported in part by DOE through USAMP (AMD 309). The focus of this project has been the identification of a standardized accelerated cosmetic corrosion test that exhibits the same appearance, severity, and type of corrosion products that are exhibited on identical painted aluminum panels exposed to service relevant environments. Multi-year service relevant exposures were conducted by mounting panels on-vehicles in multiple locations in the US and Canada.

Since 2000, an Aluminum Cosmetic Corrosion task group within the SAE Automotive Corrosion and Protection (ACAP) Committee has existed. The task group has pursued the goal of establishing a standard test method for in-laboratory cosmetic corrosion evaluations of finished aluminum auto body panels. A cooperative program uniting OEM, supplier, and consultants has been created and has been supported in part by USAMP (AMD 309) and the U.S. Department of Energy. Prior to this committee's formation, numerous laboratory corrosion test environments have been used to evaluate the performance of painted aluminum closure panels. However, correlations between these laboratory test results and in-service performance have not been established. Thus, the primary objective of this task group's project was to identify an accelerated laboratory test method that correlates well with in-service performance.

The purpose of his paper is to further the understanding of NVH test techniques for hybrid electric powertrains. It addresses dynamometer testing specifically. Due to the nature of the hybrid electric function, which includes situations when the engine is not running as well as different ratios of torque for power component combinations, typical testing methods are not adequate. Hybrid electric testing requires unique test conditions, dyno control, instrumentation and analysis. This paper attempts to establish some test standards directed specifically to the data needs of hybrid electric power trains.

Novel testing procedures and analytical methodologies to assess the performance of hybrid electric vehicle batteries have been developed. Tests include both characterization and cycle life and/or calendar life, and have been designed for both Power Assist and Dual Mode applications. Analytical procedures include a battery scaling methodology, the calculation of pulse resistance, pulse power, available energy, and differential capacity, and the modeling of calendar- and cycle-life data. Representative performance data and examples of the application of the analytical methodologies including resistance growth, power fade, and cycle- and calendar-life modeling for hybrid electric vehicle batteries are presented.

The evaluation of the performance benefits of solar load reducing glazings using production vehicles is key to the establishment of the product cost/benefit ratio. Climatic windtunnels normally used to evaluate heat gain and vehicle cooldown can not provide true solar simulation. Comparative testing using a test car and a control vehicle must therefore be conducted outside in uncontrollable ambient conditions. The subject paper deals with the development of a testing methodology capable of quantifying thermal performance differences, as low as 5%, resulting from component differences, including glazings. The procedure described includes the use of B & K Thermal Comfort Meters to standardize the refrigeration system performance and to evaluate the rate of vehicle interior cooldown. Data taken during summer test programs in the Southwest for evaluation of heat absorbing glazings will be reviewed.

A running loss test procedure has been developed which integrates a point-source collection method to measure fuel evaporative running loss from vehicles during their operation on the chassis dynamometer. The point-source method is part of a complete running loss test procedure which employs the combination of site-specific collection devices on the vehicle, and a sampling pump with sampling lines. Fugitive fuel vapor is drawn into these collectors which have been matched to characteristics of the vehicle and the test cell. The composite vapor sample is routed to a collection bag through an adaptation of the ordinary constant volume dilution system typically used for vehicle exhaust gas sampling. Analysis of the contents of such bags provides an accurate measure of the mass and species of running loss collected during each of three LA-4* driving cycles. Other running loss sampling methods were considered by the Auto-Oil Air Quality Improvement Research Program (AQIRP or Program).

As vehicle fuel economy continues to grow in importance, the ability to accurately measure the level of parasitic losses on all driveline components is required. A standardized comparison procedure enables manufacturers and suppliers to measure component losses consistently, in addition to offering a reliable process to assess enablers for efficiency improvements. This paper reviews the development of a comprehensive test procedure to measure transfer case speed-dependent parasitic losses at key speed, load, and environmental conditions. This procedure was validated for repeatability considering variations in soak time, temperature measurement positions on the transfer case, and test operating conditions. Additional assessments of spin loss at low ambient temperatures, and the effect of component break-in on spin loss were also conducted.

Downhill tests are widely used as a method of evaluation, development and validation of braking efficiency, friction pair durability, braking balance, as well as fade characteristics and recovery of friction material properties. This test procedure is used for both: passenger vehicles and light & heavy commercial vehicles. The energy levels in the brake system are higher on commercial vehicles and the thermal characteristics much more critical. Added to the fact that such tests are conducted on public highways, it has an intrinsic security risk for both the vehicle tested and all others around. Until a few years ago, it was still feasible to conduct tests downhill on different routes keeping a high security level. Given an increasing traffic on highways, where the test is currently carried out, a need to create a similar downhill procedure (called Guaporé Mountain Test) within a Proving Ground under controlled conditions has been noticed.

To better reflect real world driving conditions, the EPA 5-Cycle Fuel Economy method encompasses high vehicle speeds, aggressive vehicle accelerations, climate control system use and cold temperature conditions in addition to the previously used standard City and Highway drive cycles in the estimation of vehicle fuel economy. A standard Powersplit Hybrid Electric Vehicle (HEV) system simulation environment has long been established and widely used within Ford to project fuel economy for the standard EPA City and Highway cycles. Direct modeling and simulation of the complete 5-Cycle fuel economy test set for HEV's presents significant new challenges especially with respect to modeling vehicle thermal management system and interactions with HEV features and system controls. It also requires a structured, systematic approach to validate the key elements of the system models and complete vehicle system simulations.

Several vehicle-level test procedures exist for measuring and analyzing volatile organic compound (VOC) emissions from new vehicle interiors. In this paper, four vehicle-level procedures were examined to determine the effect of interior air temperature (driver's side breath position), ventilation, vehicle age, and solar load (intensity and source) on the total VOC concentration. A new vehicle (11 days old) was tested over five weeks at interior air temperatures of ambient, 40°C, and 50°C with the ventilation on and off. Three sources of solar load were examined with loads between 600 and 1,100 W/m₂. The three sources of solar load were 5-Zones of halogen lights, an SC03 test site with metal halide lights, and the sun. Total VOCs were measured (μg/m₃) as well as individual hydrocarbons including formaldehyde. Six temperature points in and around the vehicle were monitored over the course of each test.

A short engine sequence test, based on the Sequence VD procedure, was used to screen FFV oil candidates more rapidly. Since only one engine is needed to compare the wear-protection performance of several lubricants, engine hardware variability is not a significant issue in this test procedure. Several lubricants, some specially formulated for FFV engines, were tested using standard Sequence VD engine hardware which includes molybdenum top piston-rings. Results showed clear discrimination of the performance of oil candidates. These lubricants were also tested using an engine with chromium-faced top rings and exhibited similar performance ranking.

A comparison between ‘Quasi-Transient’ and Steady-State (SAE J1349) engine dynamometer horsepower test procedures was conducted to determine the degree of correlation between the two test methods. Measurements demonstrated that the peak horsepower and torque measured using both techniques was similar. This information is useful as a development tool, because the ‘Quasi-Transient’ procedure allows for data to be collected over the engine RPM range much faster then the Steady-State method, allowing for the accurate testing of more engine/exhaust configurations in a shorter amount of time.

Non-contacting test methodology studies of automotive body components have become a very useful, high resolution and sensitive test technique to engineering personnel. Continuous wave laser holometry, computer aided holometry (CAH), pulsed laser holometry and a scanning laser system were used to image vibration patterns. These methods were selected because of improved data turn-around time in the test development process while having no mass-loading effects on the sheet metal panels. An analysis of the vehicle body structure was conducted to improve the interior body structure sound quality and to reduce road noise presence. An interrogation of the interior noise spectrum identified critical frequencies affecting vehicle NVH. This paper addresses the results of using the aforementioned non-contacting test methods to reduce panel responses by developing an optimum rib section and pattern, and the addition of adhered stiffening materials.