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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.

Dedicated Exhaust Gas Recirculation (D-EGR®) technology provides a novel means for fuel efficiency improvement through efficient, on-board generation of H2 and CO reformate [1, 2]. In the simplest form of the D-EGR configuration, reformate is produced in-cylinder through rich combustion of the gasoline-air charge mixture. It is also possible to produce more H2 by means of a Water Gas Shift (WGS) catalyst, thereby resulting in further combustion improvements and overall fuel consumption reduction. In industrial applications, the WGS reaction has been used successfully for many years. Previous engine applications of this technology, however, have only proven successful to a limited degree. The motivation for this work was to develop and optimize a WGS catalyst which can be employed to a D-EGR configuration of an internal combustion engine. This study consists of two parts.

The diesel particulate filter (DPF) is a critical aftertreatment device for control of particulate matter (PM) emissions from a diesel engine. DPF survivability is challenged by several key factors such as: excessive thermal stress due to DPF runaway regenerations (or uncontrolled regeneration) may cause DPF substrate and washcoat failure. Catalyst poisoning elements from the diesel fuel and engine oil may cause performance degradation of the catalyzed DPF. Harsh vibration from the powertrain, as well as from the road surface, may lead to mechanical failure of the substrate and/or the matting material. Evaluations of these important validation parameters were performed.

Forty-eight materials from parts used inside and outside the passenger compartment of six motor vehicles were tested according to FMVSS 302. All samples passed the test although the FMVSS 302 test requirements do not apply to exterior materials. The same materials were also tested in the Cone Calorimeter (ASTM E 1354) at three heat fluxes. The FMVSS 302 performance diagram developed earlier on the basis of Cone Calorimeter data for 18 exterior materials from two vehicles appears to have more general validity for solid plastic parts, regardless whether they are taken from locations inside or outside of the passenger compartment. The previously-developed performance diagram is not applicable to plastic foams and fabrics. Additional criteria are proposed to predict whether a foam or fabric is likely to pass the FMVSS 302 test based on ignition time and peak heat release rate measured in the Cone Calorimeter at a heat flux of 35 kW/m2.

An Advanced Automotive Manikin (ADAM), is used to evaluate liquid cooling garments (LCG) for advanced space suits for extravehicular applications and launch and entry suits. The manikin is controlled by a finite-element physiological model of the human thermoregulatory system. ADAM's thermal response to a baseline LCG was measured.The local effectiveness of the LCG was determined. These new thermal comfort tools permit detailed, repeatable measurements and evaluation of LCGs. Results can extend to other personal protective clothing including HAZMAT suits, nuclear/biological/ chemical protective suits, fire protection suits, etc.

People who wear protective uniforms that inhibit evaporation of sweat can experience reduced productivity and even health risks when their bodies cannot cool themselves. This paper describes a new sweating manikin and a numerical model of the human thermoregulatory system that evaluates the thermal response of an individual to transient, non-uniform thermal environments. The physiological model of the human thermoregulatory system controls a thermal manikin, resulting in surface temperature distributions representative of the human body. For example, surface temperatures of the extremities are cooler than those of the torso and head. The manikin contains batteries, a water reservoir, and wireless communications and controls that enable it to operate as long as 2 hours without external connections. The manikin has 120 separately controlled heating and sweating zones that result in high resolution for surface temperature, heat flux, and sweating control.

This paper describes a study to determine the influence of preimpact vehicle braking on the positions and postures of unrestrained, children in the front seat at the time of collision. Anesthetized baboons were used as child surrogates. The unrestrained animals were placed in various initial sitting, kneeling, and standing positions typically assumed by children while traveling in automobiles. Tests were conducted with various front seat positions and seat covering materials. Measurements were made of pertinent vehicle dynamics and surrogate kinematics during the hard braking event. For each initial condition evaluated, a photosequence is given showing typical positions and postures of the surrogate during the braking event.

As governmental agencies focus on low levels of the oxides of nitrogen (NOx) emissions compliance, new off-road applications are being reviewed for both regulated and unregulated emissions to understand the technological challenges and requirements for improved emissions performance. The California Air Resources Board (CARB) has declared its intention to pursue more stringent NOX standards for the off-road market. As part of this effort, CARB initiated a program to provide a detailed characterization of emissions meeting the current Tier 4 off-road standards [1]. This work focused on understanding the off-road market, establishing a current technology emissions baseline, and performing initial modeling on potential low NOx solutions. This paper discusses a part of this effort, focuses on the emissions characterization from two non-road engine platforms, and compares the emissions species from different approaches designed to meet Tier 4 emissions regulations.

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.

Small engines which are friendly toward the environment are needed all over the world, whether the need is expressed in terms of energy efficiency, useful engine life, health benefits for the user, or emission regulations enacted to protect a population or an ecologically-sensitive area. Progress toward the widespread application of lower-impact small engines is being made through engine design, matching of engine to equipment and task, aftertreatment technology, alternative and reformulated fuels, and improved lubricants. This paper describes three research and development projects, focused on the interrelationships of fuels, lubricants, and emissions in Otto-cycle engines, which were conducted by Southwest Research Institute. All the work reported was funded internally as part of a commitment to advance the state of small engine technology and thus enhance human utility.

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 Texas Department of Transportation (TxDOT) began using an ultra-low-sulfur, low aromatic, high cetane number diesel fuel (TxLED, Texas Low Emission Diesel) in June 2003. They initiated a simultaneous study of the effectiveness to reduce emissions and influence fuel economy of this fuel in comparison to 2D on-road diesel fuel used in both their on-road and off-road equipment. The study incorporated analyses for the fleet operated by the Association of General Contractors (AGC) in the Houston area. Some members of AGC use 2D off-road diesel in their equipment. One off-road engine, two single-axle dump trucks, and two tandem-axle dump trucks were tested. The equipment tested included newer electronically-controlled diesels. The off-road engine was tested over the TxDOT Telescoping Boom Excavator Cycle. The dump trucks were tested using the “route” technique over the TxDOT Single-Axle Dump Truck Cycle or the TxDOT Tandem-Axle Dump Truck Cycle.

The Texas Department of Transportation began using an emulsified diesel fuel in 2002. They initiated a simultaneous study of the effectiveness of this fuel in comparison to 2D on-road diesel fuel and 2D off-road diesel. The study included comparisons of fuel economy and emissions for the emulsion, Lubrizol PuriNOx®, relative to conventional diesel fuels. Two engines and eight trucks, four single-axle dump trucks, and four tandem-axle dump trucks were tested. The equipment tested included both older mechanically-controlled diesels and newer electronically-controlled diesels. The two engines were tested over two different cycles that were developed specifically for this project. The dump trucks were tested using the “route” technique over one or the other of two chassis dynamometer cycles that were developed for this project In addition to fuel efficiency, emissions of NOx, PM, CO, and HCs were measured. Additionally, second-by-second results were obtained for NOx and HCs.

A dilute spark-ignited engine concept has been developed as a potential low cost competitor to diesel engines by Southwest Research Institute (SwRI), with a goal of diesel-like efficiency and torque for light- and medium-duty applications and low-cost aftertreatment. The targeted aftertreatment method is a traditional three-way catalyst, which offers both an efficiency and cost advantage over typical diesel aftertreatment systems. High levels of exhaust gas recirculation (EGR) have been realized using advanced ignition systems and improved combustion, with significant improvements in emissions, efficiency, and torque resulting from using high levels of EGR. The primary motivation for this work was to understand the impact high levels of EGR would have on particulate matter (PM) formation in a port fuel injected (PFI) engine. While there are no proposed regulations for PFI engine PM levels, the potential exists for future regulations, both on a size and mass basis.

The new Beijing Automotive Industry Corporation (BAIC) engine, an evolution of the 2.3L 4-cylinder turbocharged gasoline engine from Saab, was designed, built, and tested with close collaboration between BAIC Motor Powertrain Co., Ltd. and Southwest Research Institute (SwRI®). The upgraded engine was intended to achieve low fuel consumption and a good balance of high performance and compliance with Euro 6 emissions regulations. Low fuel consumption was achieved primarily through utilizing cooled low pressure loop exhaust gas recirculation (LPL-EGR) and dual independent cam phasers. Cooled LPL-EGR helped suppress engine knock and consequently allowed for increased compression ratio and improved thermal efficiency of the new engine. Dual independent cam phasers reduced engine pumping losses and helped increase low-speed torque. Additionally, the intake and exhaust systems were improved along with optimization of the combustion chamber design.

In this work, the influences of ethanol and iso-butanol blended with gasoline on engine-out and post three-way catalyst (TWC) particle size distribution and number concentration were studied using a General Motors (GM) 2.0L turbocharged spark ignition direct injection (SIDI) engine. The engine was operated using the production engine control unit (ECU) with a dynamometer controlling the engine speed and the accelerator pedal position controlling the engine load. A TSI Fast Mobility Particle Sizer (FMPS) spectrometer was used to measure the particle size distribution in the range from 5.6 to 560 nm with a sampling rate of 1 Hz. U.S. federal certification gasoline (E0), two ethanol-blended fuels (E10 and E20), and 11.7% iso-butanol blended fuel (BU12) were tested. Measurements were conducted at 10 selected steady-state engine operation conditions. Bi-modal particle size distributions were observed for all operating conditions with peak values at particle sizes of 10 nm and 70 nm.

A combined, experimental and numerical program is presented. This work summarizes an internal research effort conducted at Southwest Research Institute. Meeting new, stringent emissions regulations for diesel engines requires a way to reduce NOx and soot emissions. Most emissions reduction strategies reduce one pollutant while increasing the other. Water injection is one of the few promising emissions reduction techniques with the potential to simultaneously reduce soot and NOx in diesel engines. While it is widely accepted that water reduces NOx via a thermal effect, the mechanisms behind the reduction of soot are not well understood. The water could reduce the soot via physical, thermal, or chemical effects. To aid in developing water injection strategies, this project's goal was to determine how water enters the soot formation chemistry.