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This paper summarizes the Heavy-Duty In-Use Testing (HDUIT) measurement allowance program for Particulate Matter Portable Emissions Measurement Systems (PM-PEMS). The measurement allowance program was designed to determine the incremental error between PM measurements using the laboratory constant volume sampler (CVS) filter method and in-use testing with a PEMS. Two independent PM-PEMS that included the Sensors Portable Particulate Measuring Device (PPMD) and the Horiba Transient Particulate Matter (TRPM) were used in this program. An additional instrument that included the AVL Micro Soot Sensor (MSS) was used in conjunction with the Sensors PPMD to be considered a PM-PEMS. A series of steady state and transient tests were performed in a 40 CFR Part 1065 compliant engine dynamometer test cell using a 2007 on-highway heavy-duty diesel engine to quantify the accuracy and precision of the PEMS in comparison with the CVS filter-based method.

Criteria pollutants were measured from ten Class 7 and 8 (i.e., gross vehicle weights > 33,000 lb) heavy-duty diesel trucks with engine model years between 1953 and 1975. The data was used by EPA to estimate that period's particulate matter emission rates for these type engines and will be used to develop dose response relationships with existing epidemiological data. Particulate samples were analyzed for sulfate and volatile organic fraction. Carbon soot was estimated. The trucks had particulate emissions of 2 to 10 g/mi as compared to 1 to 6 g/mi for trucks with model year engines from 1975 through the mid-1980s, and less than 1 g/mi for post-1988 trucks.

In off-highway applications the engine torque is distributed between the transmission (propulsion) and other accessories such as power steering, air conditioning and implements. Electronic controls offer the opportunity to more efficiently manage the control of the engine and transmission as an integrated system. This paper deals with development of a steepest descent algorithm for maximizing the efficiency of hydrostatic transmission along with the engine in the presence of accessory load. The methodology is illustrated with an example. The strategy can be extended to the full hydro-mechanical configuration as required. Applications of this approach include adjusting for component wear and intelligent energy management between different accessories for possible size reduction of powertrain components. The potential benefits of this strategy are improved fuel efficiency and operator productivity.

Emissions from existing diesel-powered urban buses are increasingly scrutinized as local, state, and federal governments require enforcement of more stringent emission regulations and expectations. Currently, visual observation of high smoke levels from diesel-powered equipment is a popular indicator of potential emission problems requiring tune-up or engine maintenance. It is important that bus inspection and maintenance (I/M) operations have a quality control “test” to check engine emissions or diagnose the engine state-of-tune before or after maintenance. Ideally, the “emission test” would be correlated to EPA transient emissions standards, be of short duration, and be compatible with garage procedures and equipment. In support of developing a useful “short-test,” equipment was designed to collect samples of raw exhaust over a short time period for gaseous and particulate emissions.

The objective of this project was to assess the effects of various blends of biodiesel on locomotive engine exhaust emissions. Systematic, credible, and carefully designed and executed locomotive fuel effect studies produce statistically significant conclusions are very scarce, and only cover a very limited number of locomotive models. Most locomotive biodiesel work has been limited to cursory demonstration programs. Of primary concern to railroads and regulators is understanding any exhaust emission associated with biodiesel use, especially NOX emissions. In this study, emissions tests were conducted on two locomotive models, a Tier 2 EMD SD70ACe and a Tier 1+ GE Dash9-44CW with two baseline fuels, conventional EPA ASTM No. 2-D S15 (commonly referred to as ultra-low sulfur diesel - ULSD) certification diesel fuel, and commercially available California Air Resource Board (CARB) ULSD fuel.

Measurement of emissions from small utility engines has usually been accomplished using steady-state raw emissions procedures such as SAE Recommended Practice J1088. While raw exhaust measurements have the advantage of producing modal exhaust gas concentration data for design feedback; they are laborious, may influence both engine performance and the emissions themselves, and have no provision for concurrent particulate measurements. It is time to consider a full-dilution procedure similar in principle to automotive and heavy-duty on-highway emission measurement practice, leading to improvements in many of the areas noted above, and generally to much higher confidence in data obtained. When certification and audit of small engine emissions become a reality, a brief dilute exhaust procedure generating only the necessary data will be a tremendous advantage to both manufacturers and regulatory agencies.

Southwest Research Institute (SwRI) converted two small air-cooled, gasoline engines to operate on LPG (sometimes called propane since propane is LPG's major constituent). Typical two- and four-cycle engines were chosen for this investigation. The two-cycle engine used was a McCulloch string trimmer engine with 28 cc displacement. The four-cycle engine used was an L-head, Tecumseh TVS90 with 148 cc displacement. These are typical of engines found on lower cost lawn mowers and string trimmers. The engines were baseline tested on gasoline, converted to LPG, and tested to determine equivalence ratios at which the engines could be operated without exceeding manufacturers' recommended spark plug seat or exhaust temperatures. Engine startability and throttle response was maintained with the LPG conversion. The emissions of the four-cycle engine were measured following the CARB 6-mode emissions test procedure.

Development of methodology for diesel hydrocarbon speciation of C12-C22 compounds and the application of that methodology to determine total ozone forming potential of diesel exhaust emissions is an extremely complicated task. Methodology has already been developed for speciating C1-C12 exhaust emissions from engines and vehicles fueled with gasoline, diesel, and alternate fuels. However, very little or no information is available for exhaust speciation of C12-C22 compounds as sampling and analytical constraints make the collection and analysis of the higher molecular weight compounds extremely challenging. Key issues related to the definition of “hydrocarbons” also need to be addressed prior to promulgation of future reactivity-based legislation for diesels (e.g., Which exhaust hydrocarbon compounds actually exist in gas-phase and participate in atmospheric ozone formation?).

An Emergency Tire Inflation System (ETIS) designed for use on commercial trucks was evaluated and tested. The ETIS is provided in kit form and designed to be installed by a truck operator to provide emergency air to inflate a low or punctured tire on tractor drive axles. The ETIS will continue to supply air to the tire until the system pressure falls below a safe air pressure level. The system is designed to allow the rig to be driven 500 miles to a tire repair station or to a safe location where tire repair service is available. The installation kit (Figure 1), which can fit under a truck seat, includes all the necessary equipment to install the system on the most common drive axles. The ETIS supplies air to the under-inflated tire through a previously qualified1 Rotary Union design. The Rotary Union is attached to the axle flange of the drive axle by a threaded adapter and two adjustable links that allow the Rotary Union to be placed at the center of rotation of the axle.

An Automatic Tire Inflation System (ATIS), specifically designed for use on commercial long haul trailers underwent complete testing and evaluation in 1993/1994.1 Testing and evaluation included a field test of a prototype system and a controlled laboratory evaluation of the Rotary Union which is the only component subject to wear. The testing of the prototype system indicated that design improvements were necessary before the system could be installed in fleet operations. The design improvements were completed and field installation of production ATIS began. The design improvements were intended to improve overall system durability, decrease installation time, to have less effect on the axle structure than the original design, implement the use of SAE or DOT Approved pressure components and increase overall dependability of the system. ATIS systems have now been developed and tested for most domestic trailer axle configurations.

REDSOD, an acronym for Repetitive Explosive Device for Soil Displacement, utilizes the energy generated within a combustion chamber by the combustion of compressed air and a hydrocarbon fuel to displace and move soil or material. An integral wedge-shaped base shoe with a large exhaust opening in its top surface is pushed into a soil overburden at depths up to 5 ft or more by a transporting vehicle. When the combustion chamber pressure has reached a maximum value, the hot, high pressure gases are released through the exhaust opening under the soil overburden. The soil is disaggregated and displaced up and out of the excavation. Deflectors can turn the direction of the soil's trajectory to deliver it to one side of the excavation. A greatly increased productivity per unit of equipment is possible over conventional earthmoving means.

This paper describes a distributed digital process control computer designed for large industrial processing plants that has been applied successfully to laboratory engine testing. Over the past two years several complete systems have been installed and adapted to control engines from 75 kW to over 1800 kW with various dynamometer/generator absorption devices. Control problems encountered, and solutions we have found, are discussed along with the wide range of capabilities this type of system can provide. A short comparison is made between distributed digital control systems and mini-computers, listing advantages and disadvantages of both.

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.

Comparative exhaust emission tests were performed with five diesel fuels, namely a Sasol Fischer-Tropsch diesel, a fuel meeting the CARB diesel fuel specification, a fuel meeting the US 2-D diesel fuel specification, and two blends of the Fischer-Tropsch diesel and the 2-D diesel. Hot-start and cold-start heavy-duty transient emission tests were performed using a 1999 model year DDC series 60 engine. Regulated exhaust emissions with the Fischer-Tropsch diesel were significantly lower than with the 2-D and CARB diesel fuels, in both the hot-start and cold-start tests. When compared with test results obtained previously with a 1991 engine, it was found that the reduction in NOX with the Fischer-Tropsch fuel was smaller in the 1999 engine, while the reduction in PM was greater.

Particle number concentrations and size distributions were measured for the diluted exhaust of a 1991 diesel engine during the US FTP transient cycle for heavy-duty diesel engines. The engine was operated on US 2-D on-highway diesel fuel. The particle measurement system consisted of a full flow dilution tunnel as the primary dilution stage, an air ejector pump as the secondary dilution stage, and an electrical low pressure impactor (ELPI) for particle size distribution measurements. Particle number emission rate was the highest during the Los Angeles Non Freeway (LANF) and the Los Angeles Freeway (LAF) segments of the transient cycle. However, on brake specific number basis the LAF had the lowest emission level. The particle size distribution was monomodal in shape with a mode between 0.084 μm and 0.14 μm. The shape of the size distribution suggested no presence of nanoparticles below the lower detection limit of the instrument (0.032 μm), except during engine idle.