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RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.

Beginning June 1, 2006, 80% of the highway diesel fuel produced in the United States had to contain 15 ppm sulfur or less. To account for sulfur test method variability, the United States Environmental Protection Agency (US EPA) allowed a 2 ppm compliance margin, meaning that in an EPA enforcement action fuel measuring 17 ppm or less would still be deemed compliant since the true sulfur level could still be 15 ppm. Concern was voiced over the appropriateness of the 2 ppm compliance margin, citing recent American Society for Testing and Materials (ASTM) round-robin and crosscheck test program results that showed sulfur test lab-to-lab variability (reproducibility) on the order of 4 to 5 ppm depending on test method.

Results from work focusing on the development of an ultra low emissions, high efficiency, natural gas-fueled heavy- duty engine are discussed in this paper. The engine under development was based on a John Deere 8.1L engine; this engine was significantly modified from its production configuration during the course of an engine optimization program funded by the National Renewable Energy Laboratory. Previous steady-state testing indicated that the modified engine would provide simultaneous reductions in nonmethane hydrocarbon emissions and fuel consumption while maintaining equivalent or lower NOx levels. Federal Test Procedure transient tests confirmed these expectations. Very low NOx emissions, averaging 1.0 g/bhp-hr over hot-start cycles, were attained; at these conditions, reductions in engine-out nonmethane hydro-carbons emissions (NMHC) were approximately 30 percent, and fuel consumption over the cycle was also reduced relative to the baseline.

Comparative emission measurements were made in two dynamometer-based diesel engines using protocol specified by the U.S. Environmental Protection Agency (EPA) and the California Air Resources Board (CARB). A single JP-8 fuel with a sulfur level of 0.06 weight percent (wt%) was adjusted to sulfur levels of 0.11 and 0.26 wt%. The emission characteristics of the three fuels were compared to the 1994 EPA certification low-sulfur diesel fuel (sulfur level equal to 0.035 wt%) in the Detroit Diesel Corporation (DDC) 1991 prototype Series 60 diesel engine and in the General Motors (GM) 6.2L diesel engine. Comparisons were made using the hot-start transient portion of the heavy-duty diesel engine Federal Test Procedure. Results from the Army study show that the gaseous emissions for the DDC Series 60 engine using kerosene-based JP-8 fuel are equivalent to values obtained with the 0.035 wt% sulfur EPA certification diesel fuel.

Injuries produced by standard three point restraint systems with retractors will be compared between cadavers in laboratory simulated collisions at 30 mph barrier equivalent speed and lap and shoulder belted front seat occupants in real world frontal collisions of '73-'75 full sized cars. Tests conducted at SwRI with belted, unembalmed, fresh cadavers have resulted in extremely severe thoracic and cervical injuries, including multiple rib fractures, fractures of the sternum, clavicle and cervical vertebrae. On the other hand, injury data from a national accident investigation study to evaluate the effectiveness of restraints in late model passenger cars indicates that such injuries in real world crashes of equivalent severity are not always observed. The reasons possible for these differences are discussed. Both programs at SwRI are funded by the National Highway Traffic Safety Administration.

Radioactive tracer technology is an important tool for measuring component wear on a real-time basis and is especially useful in measuring engine wear as it is affected by combustion system operation and lubricant performance. Combustion system operation including the use of early and/or late fuel injection and EGR for emissions control can have a profound effect on aftertreatment contamination and engine reliability due to wear. Liner wear caused by localized fuel impingement can lead to excessive oil consumption and fuel dilution can cause excessive wear of rings and bearings. To facilitate typical wear measurement, the engine's compression rings and connecting rod bearings are initially exposed to thermal neutrons in a nuclear reactor to produce artificial radioisotopes that are separately characteristic of the ring and bearing wear surfaces.

Radioactive tracer technology (RAT) is an important tool in measuring component wear in an operating engine on a real-time basis. This paper will discuss the use of RAT to study and evaluate boundary lubricant and surfactant chemistries aimed at providing benefits in wear control. In particular, RAT was employed to study ring and bearing wear as a function of engine operating condition (speed, load, and temperature) and lubricant characteristics. Prior to testing, the engine's compression rings and connecting rod bearings were subjected to bulk thermal neutron bombardment in a nuclear reactor to produce artificial radioisotopes that were separately characteristic of the ring and bearing wear surfaces. The irradiated parts were installed in the test engine, after which testing to a specific test matrix was accomplished.

The Port Fuel Injector (PFI) Deposit Test is a performance-based test procedure developed by the Coordinating Research Council and adopted by state and federal regulatory agencies for fuel qualification in the United States. To date, Southwest Research Institute (SwRI) has performed over 375 PFI tests between 1991 and 1998 for various clients. This paper details the analyses of these tests. Of the 375 tests, 199 were performed as keep-clean tests and 176 were performed as clean-up tests. The following areas of interest are discussed in this paper: Keep-clean versus clean-up test procedures Linearity of deposit formation Injector position effects as related to fouling Dirtyup / cleanup phenomena Seasonal effects This paper draws the conclusion that it is easier to keep new injectors from forming deposits than it is to clean up previously formed deposits. It was found that injector deposit formation is generally non-linear.

Several techniques have been developed to measure the relative amount of splash and spray produced by vehicles when driven on wet roads at highway speeds under controlled conditions. This paper discusses considerations in the development of measurement techniques such as those utilizing photographs, a photometer, densitometer, spraymeter, and spray collector. The development of each technique is described. Some test data utilizing the photometer and densitometer techniques are presented in a comparison of two different trucks run on two different road surfaces with new and worn tires, fully loaded and unloaded, and under light and heavy road moisture conditions.

Over twenty prototype hybrid buses and other commercial vehicles are currently being completed and deployed. These vehicles are primarily “series” hybrid vehicles which use electric motors for primary traction while internal combustion engines, or high-speed turbine engines connected to generators, supply some portion of the electric propulsion and battery recharge energy. Hybrid-electric vehicles have an electric energy storage system on board that influences the operation of the heat engine. The storage system design and level affect the vehicle emissions, electricity consumption, and fuel economy. Existing heavy-duty emissions test procedures require that the engine be tested over a transient cycle before it can be used in vehicles (over 26,000 lbs GVW). This paper describes current test procedures for assessing engine and vehicle emissions, and proposes techniques for evaluating engines used with hybrid-electric vehicle propulsion systems.

Port-fuel-injection (PFI) problems were first reported late in 1984. Deposits that formed on the tip of the pintle-type injectors of certain engines restricted fuel flow and caused driveability and emission problems. Responding to this problem, industry test programs were initiated to reproduce the deposits under controlled conditions. In 1986, a vehicle test procedure was identified and the automotive industry recommended a pass/fail performance level. Building upon available information, the Coordinating Research Council's (CRC) Port Fuel Injector Deposit Group developed a standard vehicle test procedure to evaluate various unleaded gasolines for port-fuel-injection fouling. The vehicle test procedure was adopted as an ASTM test method. The United States Environmental Protection Agency (EPA) and the State of California accepted the procedure as the standard for measuring a gasoline's propensity to form deposits in a pintle-type injector.

This paper traces the evolution of the ASTM Test Monitoring Center (TMC) from its modest beginnings in 1976 to the present. Formed as an unbiased and non-aligned group within ASTM Subcommittee D02.B, the TMC operates a reference oil based calibration system that serves both the producers and users of automotive lubricants. Governed by the ASTM Test Monitoring Board, the center's primary mission is to calibrate engine dynamometer test stands used to conduct various ASTM test methods for evaluating lubricant performance. The core services of the TMC have remained the same over its nearly 25 year history. The center stores and distributes ASTM reference oils and is responsible for assuring, through the use of analytical testing, the quality and consistency of the oils. The number of reference oils handled by the TMC has steadily increased over time such that today the center inventories some 100 different formulations having a total volume of 65,000 gallons.

The Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) awarded a contract to Southwest Research Institute (SwRI) to conduct research and testing in the interest of motorcoach fire safety. The goal of this program was to develop and validate procedures and metrics to evaluate current and future detection, suppression, and exterior fire-hardening technologies that prevent or delay fire penetration into the passenger compartment of a motorcoach - in order to increase passenger evacuation time. The program was initiated with a literature review and characterization of the thermal environment of motorcoach fires and survey of engine compartments, firewalls, and wheel wells of motorcoaches currently in North American service. These characterizations assisted in the development of test methods and identification of the metrics for analysis. Test fixtures were designed and fabricated to simulate a representative engine compartment and wheel well.

In 2012, NHTSA and EPA extended Corporate Average Fuel Economy (CAFE) standards for light duty vehicles through the 2025 model year. The new standards require passenger cars to achieve an average of five percent annual improvement in fuel economy and light trucks to achieve three percent annual improvement. This regulatory requirement to improve fuel economy is driving research and development into fuel-saving technologies. A large portion of the current research is focused on incremental improvements in fuel economy through technologies such as new lubricant formulations. While these technologies typically yield less than two percent improvement, the gains are extremely significant and will play an increasing role in the overall effort to improve fuel economy. The ability to measure small, but statistically significant, changes in vehicle fuel economy is vital to the development of new technologies.

A heavy duty (150 kW) diesel engine was tested to determine operational problems while running on minimally processed synthetic fuels. A reference No. 2 diesel fuel was compared with liquid products derived from shale, tar sands, and coal. Information on the engine setup and test procedure is presented. The test results include engine power, thermal efficiency, ignition delay, gaseous and particulate emissions, smoke opacity, cylinder pressure, and heat release data. Cold start data at 0°C and −20° C and idle deposit test results are also presented. These data should help to determine future engine modifications to enhance synfuel engine performance.

The SwRI/BMW N.A. Intake Valve Deposit Test procedure was the first performance-based test procedure adopted for fuels qualification in the United States. The initial fuel evaluations were begun in January 1988 with six 1985 BMW 318i vehicles. Since that time, the fleet has grown to include over 60 BMW cars, and more than 2000 tests have been performed. This paper gives a statistical summary of approximately 1800 tests performed over a four-year period. Performance data and possible sources of test variation are discussed. Data and analyses offered represent results of tests by all clients. However, data is presented such that no individual test or client is identified.

A study was performed to develop optimum design strategies for a production V6 engine to maximize catalyst performance at minimum pressure loss and at minimum cost. Test results for an advanced system, designed to meet future emission limits on a production V6 vehicle, are presented based on FTP testing. The on-line pressure loss and temperature data serves to explain the functioning of the catalyst.

This paper discusses the techniques and diagnostic significance of atomic absorption, atomic emission, and infrared spectrometric analysis of crankcase lubricants, with the use of supplementary data where pertinent. The parameters affecting used oil analytical data are discussed in terms of examples from Army general purpose vehicle test engines. Wear metals in used gear oils are also discussed and examples are given. Analytical methods and their applications are fully described, and the equipment and procedures for infrared spectroscopy and gas chromatography techniques are outlined.

The optical spark plug probe and ionization head gasket probe developed at Sandia Laboratories were applied to one cylinder of a production multicylinder automotive gasoline engine. The purpose of this application is to eventually study combustion phenomena leading to high emissions under cold start and cold idle conditions. As a first step in studying cold start combustion and emissions issues, diagnostic instrumentation was simultaneously applied to a production engine under steady state idle, road load and an intermediate load-speed condition. The preliminary application of such instrumentation is the subject of the present paper. The spark plug probe was redesigned for ease of use in production engines and to provide a more robust design. The two probes were geometrically oriented to obtain radial line-up between the optical windows and ionization probes. Data were taken simultaneously with both probes at the three load-speed conditions mentioned above.

Selective catalytic reduction (SCR) catalysts will be used to reduce oxides of nitrogen (NOx) emissions from internal combustion engines in a number of applications. Southwest Research Institute® (SwRI)® performed an Internal Research & Development project to study SCR catalyst thermal deactivation. The study included a V/W/TiO₂ formulation, a Cu-zeolite formulation and an Fe-zeolite formulation. This work describes NOx timed response to ammonia (NH₃) transients as a function of thermal aging time and temperature. It has been proposed that the response time of NOx emissions to NH₃ transients, effected by changes in diesel emissions fluid (DEF) injection rate, could be used as an on-board diagnostic (OBD) metric. The objective of this study was to evaluate the feasibility and practicality of this OBD approach.