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Technical Paper

Emissions Reduction Performance of a Bimetallic Platinum/Cerium Fuel Borne Catalyst with Several Diesel Particulate Filters on Different Sulfur Fuels

2001-03-05
2001-01-0904
Results of engine bench tests on a 1998 heavy-duty diesel engine have confirmed the emissions reduction performance of a U.S. Environmental Protection Agency (EPA) registered platinum/cerium bimetallic fuel borne catalyst (FBC) used with several different catalyzed and uncatalyzed diesel particulate filters (DPF's). Performance was evaluated on both a 450ppm sulfur fuel (No.2 D) and a CARB 50ppm low sulfur diesel (LSD) fuel. Particulate emissions of less than 0.02g/bhp-hr were achieved on several combinations of FBC and uncatalyzed filters on 450ppm sulfur fuel while levels of 0.01g/bhp-hr were achieved for both catalyzed and uncatalyzed filters using the FBC with the low sulfur CARB fuel. Eight-mode steady state testing of one filter and FBC combination with engine timing changes produced a 20% nitrogen oxide (NOx) reduction with particulates (PM) maintained at 0.01g/bhp-hr and no increase in measured fuel consumption.
Technical Paper

Ultra Low Emissions and High Efficiency from an On-Highway Natural Gas Engine

1998-05-04
981394
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.
Technical Paper

The Challenges of Developing an Energy, Emissions, and Fuel Economy Test Procedure for Heavy-Duty Hybrid Electric Transit Vehicles

1995-11-01
952610
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.
Technical Paper

Analysis of a Novel Two-Stroke Engine Scavenging Arrangement: The Neutron Engine

1995-09-01
952140
A unique two-stroke engine design is investigated in which fresh mixture is introduced into the cylinder through a valve in the piston crown, and exhausted through peripheral cylinder ports. The engine behaves as a free-piston engine through a portion of the cycle when the piston lifts off the valve seat. The fresh air jet rising along the cylinder centerline effectively displaces the burned gases with little mixing of the two streams. The concept was analyzed by a combination of dynamic cycle simulation and prediction of the in-cylinder flow characteristics by multidimensional modeling. The cycle simulation program considered the dynamics of the piston during its free motion as well as under the kinematic constraints of the crank system. A zero-dimensional thermodynamic model of the cylinder was used to predict cycle pressure and temperature, indicated power, fuel consumption, and flow in and out of the cylinder.
Technical Paper

Emissions From Snowmobile Engines Using Bio-based Fuels and Lubricants

1997-10-27
978483
Snowmobile engine emissions are of concern in environmentally sensitive areas, such as Yellowstone National Park (YNP). A program was undertaken to determine potential emission benefits of use of bio-based fuels and lubricants in snowmobile engines. Candidate fuels and lubricants were evaluated using a fan-cooled 488-cc Polaris engine, and a liquid-cooled 440-cc Arctco engine. Fuels tested include a reference gasoline, gasohol (10% ethanol), and an aliphatic gasoline. Lubricants evaluated include a bio-based lubricant, a fully synthetic lubricant, a high polyisobutylene (PIB) lubricant, as well as a conventional, mineral-based lubricant. Emissions and fuel consumption were measured using a five-mode test cycle that was developed from analysis of snowmobile field operating data.
Technical Paper

Homogeneous Charge Compression Ignition (HCCI) of Diesel Fuel

1997-05-01
971676
This paper describes the ongoing homogeneous charge compression ignition (HCCI) research being carried out at Southwest Research Institute (SwRI). Summaries of the results of testing to date are presented and discussed. HCCI is a process whereby a premixed charge of diesel fuel and air is admitted into the power cylinder and compression ignited. Ignition occurs homogeneously throughout the cylinder. HCCI reduces flame temperatures and oxides of nitrogen (NOx) emissions. The lack of fuel rich zones within the cylinder eliminates soot formation (1-pull Bosch smoke numbers of 0, 5-pull = 0). The limits of HCCI start of combustion timing are defined by knock before top dead center (BTDC) and misfire after top dead center (ATDC). Stable and repeatable HCCI combustion has been demonstrated over a wide range of air-fuel (A/F) ratios, intake temperatures, compression ratios (CR), exhaust gas recirculation (EGR) rates, and for two fuels. A/F ratios of 14 to 80 are possible.
Technical Paper

Analysis of a Hybrid Powertrain for Heavy Duty Trucks

1995-11-01
952585
Heavy duty trucks account for about 50 percent of the NOx burden in urban areas and consume about 20 percent of the national transportation fuel in the United States. There is a continuing need to reduce emissions and fuel consumption. Much of the focus of current work is on engine development as a stand-alone subsystem. While this has yielded impressive gains so far, further improvement in emissions or engine efficiency is unlikely in a cost effective manner. Consequently, an integrated approach looking at the whole powertrain is required. A computer model of the heavy duty truck system was built and evaluated. The model includes both conventional and hybrid powertrains. It uses a series of interacting sub-models for the vehicle, transmission, engine, exhaust aftertreatment and braking energy recovery/storage devices. A specified driving cycle is used to calculate the power requirements at the wheels and energy flow and inefficiencies throughout the drivetrain.
Technical Paper

An Unthrottled Gaseous Fuel Conversion of a 2-Stroke Diesel Engine

1975-02-01
750159
The feasibility of converting a conventional unthrottled 2-stroke diesel engine to gaseous fuel was investigated. The development work was performed in two phases. In phase 1 the conversion concepts were built and tested on a single-cylinder engine. In phase 2 one of these was put into effect in a 6-cyl (DDA 6V-71) engine. The design concept with the most promise includes a divided combustion chamber utilizing a gas inlet valve in each chamber and a spark plug ignition source located in the prechamber. The concept has the potential of reducing the exhaust emissions well below the levels now existing in commercial diesels without exhaust smoke and odor and with equivalent fuel consumption and horsepower, as demonstrated in the single-cylinder conversion. Further development work remains to be done to perfect the concept for the multi-cylinder engine.
Technical Paper

Soak Time Effects on Car Emissions and Fuel Economy

1978-02-01
780083
Five light-duty vehicles were used to investigate HC, CO, and NOx emissions and fuel economy sensitivity to changes in the length of soak period preceding the EPA Urban Dynamometer Driving Schedule (UDDS). Emission tests were conducted following soak periods 10 minutes to 36 hours in length. Each of the first 8 minutes of the driving cycle was studied separately to observe vehicle warm-up. Several engine and fuel system temperatures were monitored during soak and run periods and example trends are illustrated. The extent to which emission rates and fuel consumption are affected by soak period length is discussed.
Technical Paper

Application of On-Highway Emissions Technology on a Scraper Engine

1992-04-01
920923
An investigation was performed to determine the effects of applying on-highway heavy-duty diesel engine emissions reduction technology to an off-highway version of the engine. Special attention was paid to the typical constraints of fuel consumption, heat rejection, packaging and cost-effectiveness. The primary focus of the effort was NOx, reduction while hopefully not worsening other gaseous and particulate emissions. Hardware changes were limited to “bolt-on” items, thus excluding piston and combustion chamber modifications. In the final configuration, NOx was improved by 28 percent, particulates by 58 percent, CO and HC were also better and the fuel economy penalty was limited to under 4 percent. Observations are made about the effectiveness of various individual and combined strategies, and potential problems are identified.
Technical Paper

Technology Demonstration of U.S. Army Ground Materiel Operating on Aviation Kerosene Fuel

1992-02-01
920193
A technology demonstration program was conducted by the U.S. Army to verify the feasibility of using aviation turbine fuel JP-8 in all military diesel fuel-consuming ground vehicles and equipment (V/E). Over 2,800 pieces of military equipment participated in a two and one-half year program accumulating over 2,621,000 total miles (4,219,810 km) using JP-8 in combat/tracked, tactical/wheeled, and transportation motor pool vehicles. Over 71,000 hours of operation were accumulated in diesel/turbine engine-driven generator sets using JP-8 fuel. Comparisons of various performance areas with baseline diesel fuel (DF-2) operation were made.
Technical Paper

The Development of the Pumpless Gas Engine Concept

1970-02-01
700073
The major events in the development of a “pumpless” gas engine concept are related. The immediate objective of the subject program was to develop a combustion system for natural gas fueled engines which, when compared with conventional gas engines, would be operationally simpler and easier to maintain with no appreciable penalty in specific fuel consumption. The pumpless gas principle was successfully demonstrated on a single-cylinder, 2-cycle engine. The concept was then extended, with the aid of combustion photography, to a single-cylinder, 4-cycle laboratory engine. The feasibility of the concept was further demonstrated by the conversion of a commercially available 4-cycle, 4-cyl diesel engine.
Technical Paper

Piston-Turbine-Compound Engine — A Design and Performance Analysis

1965-02-01
650632
Exhaust heat utilization for internal combustion engines has centered around turbosupercharging in recent years, neglecting the promising field of compounding a piston engine with a gas turbine in which, unlike turbocharging, turbine power is fed back to the engine crankshaft. The piston engine can cope with high gas pressure and temperature, whereas the gas turbine can efficiently utilize the energy at relatively low pressure and temperature and large volume flows. By compounding, this-piston engine will handle the high pressure, high temperature phase of the combustion cycle and extend the expansion ratio of the gases to atmospheric pressure by completing the low pressure, low temperature phase in the gas turbine. The marriage of the two engines will result in an outstanding power package with the highest thermal efficiency possible.
Technical Paper

Control of Diesel Exhaust Emissions in Underground Coal Mines - Single-Cylinder Engine Optimization for Water-in-Fuel Miscroemulsions

1983-02-01
830553
The increased use of diesel-powered equipment in underground mines has prompted interest in reducing their exhaust pollutants. Control of particulate emissions without substantial penalties in other emissions or fuel consumption is necessary. This paper describes test results on a prechaaber, naturally-aspirated, four-cycle diesel engine in which two different concentrations of water-in-fuel emulsions were run. The independent variables comprising the test matrix were fuel, speed, load, injection timing, injection rate, and compression ratio. The dependent variables of the experiment included particulate and gaseous emissions and engine thermal efficiency. Regression analysis was performed on the data to determine how particulate emissions were affected by fuel and engine parameters. Results of this analysis indicated that substantial reductions in particulate emissions could be obtained by utilizing water-in-fuel emulsions.
Technical Paper

Fuel Consumption of Crawler Tractors

1982-02-01
821081
In this paper, a mathematical model is used to determine the fuel-consuming characteristics of a typical crawler tractor with bulldozer under various opera ting regimes. The results are used to suggest various methods to reduce tractor fuel consumption.
Technical Paper

Emissions from Trucks by Chassis Version of 1983 Transient Procedure

1980-10-01
801371
Regulated gaseous, particulate and several unregulated emissions are reported from four heavy-duty diesel engines operated on the chassis version of the 1983 transient procedure. Emissions were obtained from Caterpillar 3208, Mack ENDT 676, Cummins Formula 290 and Detroit Diesel 8V-71 engines with several diesel fuels. A large dilution tunnel (57′ × 46″ ID) was fabricated to allow total exhaust dilution, rather than the double dilution employed in the stationary engine version of the transient procedure. A modal particulate sampler was developed to obtain particulate data from the individual segments of the 1983 transient procedure. The exhaust gas was analyzed for benzo(a)pyrene, metals, N2O, NO2, individual hydrocarbons and HCN. Sequential extractions were performed and measured versus calculated fuel consumptions were obtained.
Technical Paper

Evaluation of Emission Control Technology Approaches for Heavy-Duty Gasoline Engines

1978-02-01
780646
This paper summarizes a laboratory effort toward reducing nine-mode cycle composite emissions and fuel consumption in a heavy-duty gasoline engine, while retaining current durability performance. Evaluations involved standard carburetors, a Dresserator inductor, a Bendix electronic fuel injection system, exhaust manifold thermal reactors, and exhaust gas recirculation, along with other components and engine operating parameters. A system consisting of electronic fuel injection, thermal reactors with air injection and exhaust gas recirculation, was assembled which met specified project goals. An oxidation catalyst was included as an add-on during the service accumulation demonstration. In addition, the driveability of this engine configuration was demonstrated.
Technical Paper

Fuel Efficiency Effects of Lubricants in Military Vehicles

2010-10-25
2010-01-2180
The US Army is currently seeking to reduce fuel consumption by utilizing fuel efficient lubricants in its ground vehicle fleet. An additional desire is for a lubricant which would consist of an all-season (arctic to desert), fuel efficient, multifunctional Single Common Powertrain Lubricant (SCPL) with extended drain capabilities. To quantify the fuel efficiency impact of a SCPL type fluid in the engine and transmission, current MIL-PRF-46167D arctic engine oil was used in place of MIL-PRF-2104G 15W-40 oil and SAE J1321 Fuel Consumption In-Service testing was conducted. Additionally, synthetic SAE 75W-140 gear oil was evaluated in the axles of the vehicles in place of an SAE J2360 80W-90 oil. The test vehicles used for the study were three M1083A1 5-Ton Cargo vehicles from the Family of Medium Tactical Vehicles (FMTV).
Technical Paper

Evaluation of Hydraulic Efficiency Using High-Shear Viscosity Fluids

2010-10-25
2010-01-2178
Fossil fuel consumption is a significant factor in terms of both economic and environ-mental impact of on- and off-highway systems. Because fuel consumption can be directly tied to equipment efficiency, gains in efficiency can lead to reduction in operating costs as well as conservation of nonrenewable resources. Fluid performance has a direct effect on the efficiency of a hydraulic system. A procedure has been developed for measuring a fluid's effect on the degree to which mechanical power is efficiently converted to hydraulic power in pumps typical of off-highway applications.
Technical Paper

Diesel Catalyst Aging using a FOCAS® HGTR, a Diesel Burner System, to Simulate Engine-Based Aging

2010-04-12
2010-01-1218
The classical approach to prepare engine exhaust emissions control systems for evaluation and certification is to condition the fresh parts by aging the systems on an engine/dynamometer aging stand. For diesel systems this can be a very lengthy process since the estimated service life of the emissions control systems can be several hundred thousand miles. Thus full useful life aging can take thousands of engine bench aging hours, even at elevated temperatures, making aging a considerable cost and time investment. Compared to gasoline engines, diesel engines operate with very low exhaust gas temperatures. One of the major sources of catalyst deactivation is exposure to high temperature [ 1 ].
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