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The objective of this project, which is supported by the U.S. Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL), is to provide a comprehensive comparison of heavy-duty trucks operating on alternative fuels and diesel fuel. Data collection from up to eight sites is planned. This paper summarizes the design of the project and early results from the first two sites. Data collection is planned for operations, maintenance, truck system descriptions, emissions, duty cycle, safety incidents, and capital costs and operating costs associated with the use of alternative fuels in trucking.

Performance of various plastic abrasive materials is compared in a typical aerospace coatings removal application. Media aggressiveness towards substrates, stripping capabilities, effects of plastic breakdown, and plastic consumption are compared. Lower density plastics are shown to be more substrate protective than higher denisty plastics. Stripping rates are shown to be dependent both on plastic hardness and breakdown resistance of the plastic.

Of the several types of performance-based brake testers (PBBTs), roller dynamometers (RDs) have been used for more than 20 years in Europe to judge the braking capabilities of commercial vehicles and for enforcement of minimum brake performance requirements. These RDs, however, have been exclusively of the in-ground design. In recent years, both in Australia as well as in the United States, the use of portable RDs for assessing commercial vehicle braking performance has been increasing. This paper describes some of the differences between the two types of RDs. Analyses of the effect of the roll geometry and coefficient of friction on maximum brake force measurements are made. It is concluded that careful considerations must be taken with the use of such measurements for predicting stopping distance and braking stability using the results from both in-ground as well as portable RDs. Recommendations are made based on the results of the analyses.

The ability of performance-based brake testers (PBBTsa) to accurately determine the braking capability of commercial vehicles was investigated through a field study of over 2,800 trucks and buses. Under certain conditions, good agreement was found between the observation of brake-related defects by visual inspection and the measurement of weak brake forces by a PBBT. It was determined that the PBBTs' assessment was an independent measure of a vehicle's as-is braking capability, and should not be expected to correlate well with a visual inspection under any condition. It was also determined that predictions of stopping capability should be possible combining the PBBT results of the brake force and axle load measurements with certain assumptions regarding brake application time and road/tire coefficient of friction.

The impact dynamics of full-scale heavy-vehicle rollover events were quantitatively evaluated. Videotapes of a variety of rollover events were collected. One tractor-semitrailer combination was rolled by a sudden steer, two combinations rolled after a barrier impact, and one straight truck was pulled down an embankment. The videotapes were analyzed to estimate the vehicles' roll rates and their vertical velocities upon striking the ground. These experimental values corroborate the results of vehicle dynamic simulations that had been previously conducted to replicate actual rollover crashes. Those crashes were the subject of an NTSB Special Investigation Report that examined the crashworthiness of cargo tank trucks carrying hazardous materials.

This paper summarizes the Next Generation Natural Gas Vehicle (NG-NGV) Program that is led by the U.S. Department Of Energy's (DOE's) Office of Heavy Vehicle Technologies (OHVT) through the National Renewable Energy Laboratory (NREL). The goal of this program is to develop and implement one Class 3-6 compressed natural gas (CNG) prototype vehicle and one Class 7-8 liquefied natural gas (LNG) prototype vehicle in the 2004 to 2007 timeframe. OHVT intends for these vehicles to have 0.5 g/bhp-hr or lower emissions of oxides of nitrogen (NOx) by 2004 and 0.2 g/bhp-hr or lower NOx by 2007. These vehicles will also have particulate matter (PM) emissions of 0.01 g/bhp-hr or lower by 2004. In addition to ambitious emissions goals, these vehicles will target life-cycle economics that are compatible with their conventionally fueled counterparts.

A program has been completed to evaluate ultra-low sulfur diesel fuels and passive diesel particulate filters (DPFs) in truck and bus fleets operating in southern California. The fuels, ECD and ECD-1, are produced by ARCO (a BP Company) and have less than 15 ppm sulfur content. Vehicles were retrofitted with two types of catalyzed DPFs, and operated on ultra-low sulfur diesel fuel for over one year. Exhaust emissions, fuel economy and operating cost data were collected for the test vehicles, and compared with baseline control vehicles. Regulated emissions are presented from two rounds of tests. The first round emissions tests were conducted shortly after the vehicles were retrofitted with the DPFs. The second round emissions tests were conducted following approximately one year of operation. Several of the vehicles retrofitted with DPFs accumulated well over 100,000 miles of operation between test rounds.

Currently the U. S. Department of Defense (DoD) exclusively uses potassium acetate (KAc)-based runway deicing fluids (RDFs) to deice and anti-ice military runways and taxiways. Commercial airports predominantly use KAc, but some also use RDFs composed of KAc plus propylene glycol (PG) or urea plus PG. Conventional RDFs have environmental concerns due to toxicity as well as material compatibility problems such as corrosion of aircraft carbon brake-pad components, cadmium-plated landing gear, and airfield lighting fixtures. Under the Strategic Environmental Research and Development Program (SERDP), Battelle tested a series of patented - bio-based RDFs to address these issues. Tests showed that the Battelle RDFs met the mandatory Aerospace Material Specification (AMS) 1435 requirements. These new RDFs have reduced ecotoxicity compared to currently used RDFs and are compliant with all other environmental requirements.

Both field research and certification data show that the lean burn natural gas powered spark ignition engines offer particulate matter (PM) reduction with respect to equivalent diesel power plants. Concerns over PM inventory make these engines attractive despite the loss of fuel economy associated with throttled operation. Early versions of the Cummins L-10 natural gas engines employed a mixer to establish air/fuel ratio. Emissions measurements by the West Virginia University Transportable Heavy Duty Emissions Testing Laboratories on Cummins L-10 powered transit buses revealed the potential to offer low emissions of PM and oxides of nitrogen, (NOx) but variations in the mixture could cause emissions of NOx, carbon monoxide and hydrocarbons to rise. This was readily corrected through mixer repair or readjustment. Newer versions of the L-10 engine employ a more sophisticated fueling scheme with feedback control from a wide range oxygen sensor.

VTOL and STOL aircraft play a significant role in the ever increasing mobility of the Armed Forces. The landing gear of these aircraft must be able to operate from rough, unprepared fields and must support the aircraft on soft soil as well as on irregular and pothole terrain. This paper discusses the requirements of such gear and describes the development and design characteristics of tires and equipment that meet performance needs.

After several alternative procedures were investigated for preparing chromium-plated zinc die castings for painting, one procedure proved best for contaminated chromium surfaces. This procedure included six steps: (1) alkaline spray cleaning, (2) electrolytic alkaline cleaning, (3) rinsing with high-purity water with a specific resistance of 500,000-700,000 ohm-cm, (4) immersing in chromic acid solution (0.05 oz/gal) at 150 F for 2 minutes, or treating cathodically in 0.7 oz/gal of sodium dichromate with a current density of 0.05 amp/sq ft for 30-60 sec, (5) rinsing with high-purity water, (6) forced-air drying with filtered air at 15 psi. Good adherence was obtained by following these procedures and painting with a single coat of acrylic or alkyd-resin paint. Other preparation procedures resulted in inferior paint adherence.

THIS report of a survey of hydraulic packings, especially O-ring seals, covers friction studies, torsional strength tests, plasticizer development, a study of rubbers, molding technique, and spiral failure. The Institute is reported to be planning to conduct research work along the lines of cycling tests and studies of stress aging, compounding, and backup rings.

The process for certifying an existing aircraft for flight into known icing is well defined and must follow specific guidelines and meet specific milestones. As UAVs are still a relatively recent development, guidelines for icing flight certification of a UAV have not yet been developed by the FAA, and no UAVs have yet been certified for FIKI under the FAA. As part of a research program, engineers at the Battelle Memorial Institute in Columbus, OH USA worked with partners to integrate its ice protection system, HeatCoatTM, onto an existing UAV platform as a retrofit with the ultimate goal of flying in icing conditions. This research program was funded by the US Government with intent to integrate HeatCoat on the TigerShark-XP UAV. The integration on the TigerShark was demonstrated to present challenges specific to the nature of this UAV that had to be overcome.

This paper addresses the modeling issues of resistance spot welds. The state of the art modeling techniques on weld process simulation, weld property prediction and weld engineering performance evaluation are presented. First, weld process simulation is performed using the incrementally coupled thermal-electrical-mechanical analyses. The resulted weld nugget size, weld residual stress and weld material property distributions are then used in determining the static performance of a single weld coupon. Comparisons with experimental measurements are presented as validations. Results generated from this single weld coupon is then used in the simulation of dynamic crush mechanism of a spot welded single hat section.

A study was conducted to assess the status of the antilock brake system (ABS) malfunction warning system on in-service air-braked commercial motor vehicles (CMVs). Data from a total of approximately 1,000 CMVs were collected in California, Ohio, Pennsylvania, and Washington in August and September of 2004 by enforcement personnel who had been trained to inspect the ABS warning lamp. With four categories covering warning lamp system functionality; no lamp (including lamp could not be found), lamp inoperational (including covered up or bulb removed), lamp ON (thus indicating an active ABS system fault), or OK, a snapshot of the operational status of the ABS malfunction warning system was created for the CMV population checked. Results indicate that about one in six power units manufactured on or after March 1, 1997 showed some problem with their ABS warning lamp system. One in three trailers manufactured on or after March 1, 1998 showed a problem.