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A project was conducted by Southwest Research Institute on behalf of the California Air Resources Board and the South Coast Air Quality Management District to demonstrate the technical feasibility of utilizing closed-loop three-way catalyst technology in off-road equipment applications. Five representative engines were selected, and baseline emission-tested using both gasoline and LPG. Emission reduction systems, employing three-way catalyst technology with electronic fuel control, were designed and installed on two of the engines. The engines were then installed in a fork lift and a pump system, and limited durability testing was performed. Results showed that low emission levels, easily meeting CARB's newly adopted large spark-ignited engine emission standards, could be achieved.

A new approach to reclaiming the spoil areas produced by area-type mining operations has been developed. This system uses a machine known as a winch-dozer, consisting of a pair of large back-to-back buckets which are drawn by cable across spoil piles, moving back and forth between a “tailblock” anchor and a “drawworks” winch unit developed as an attachment to a large crawler tractor. The system is expected to reduce the cost of reclamation leveling by 40-50%. The system permits more effective power utilization due to the blade system's light weight, induces caving of spoil banks, and permits moving spoil in both directions of blade travel.

The Texas Department of Transportation (TxDOT) began using an emulsified diesel fuel in July 2002. They initiated a simultaneous study of the effectiveness of this fuel in comparison to 2D on-road diesel fuel, which they use in both their on-road and off-road equipment. The study also incorporated analyses for the fleet operated by the Associated General Contractors (AGC) in the Houston area. Some members of AGC use 2D off-road diesel fuel in their equipment. The study included comparisons of fuel economy and emissions for the emulsified fuel relative to the conventional diesel fuels. Cycles that are known to be representative of the typical operations for TxDOT and AGC equipment were required for use in this study. Four test cycles were developed from data logged on equipment during normal service: 1) the TxDOT Telescoping Boom Excavator Cycle, 2) the AGC Wheeled Loader Cycle, 3) the TxDOT Single-Axle Dump Truck Cycle, and 4) the TxDOT Tandem-Axle Dump Truck Cycle.

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.

This paper describes an in-cylinder lean-rich combustion (no-post-injection for rich) switching control approach for modern diesel engines equipped with exhaust-treatment systems. No-post-injection rich combustion is desirable for regeneration of engine exhaust-treatment systems thanks to its less fuel penalty compared with regeneration approaches using post-injections and / or in-exhaust injections. However, for vehicle applications, it is desirable to have driver-transparent exhaust-treatment system regenerations, which challenge the in-cylinder rich-lean combustion transitions. In this paper, a nonlinear in-cylinder condition control system combined with in-cylinder condition guided fueling control functions were developed to achieve smooth in-cylinder lean-rich switching control at both steady-state and transient operation. The performance of the control system is evaluated on a modern light-duty diesel engine (G9T600).

The process of developing, parameterizing, validating, and maintaining models occurs within a wide variety of tools, and requires significant time and resources. To maximize model utilization, models are often shared between various toolsets and experts. One common example is sharing aircraft engine models with airframers. The functionality of a given model may be utilized and shared with a secondary model, or multiple models may run collaboratively through co-simulation. There are many technical challenges associated with model sharing and co-simulation. For example, data communication between models and tools must be accurate and reliable, and the model usage must be well-documented and perspicuous for a user. This requires clear communication and understanding between computer scientists and engineers. Most often, models are developed by engineers, whereas the tools used to share the models are developed by computer scientists.

The engine intake process governs many aspects of the flow within the cylinder. The inlet valve is the minimum area, so gas velocities at the valve are the highest velocities seen. Geometric configuration of the inlet ports and valves, and the opening schedule create organized large scale motions in the cylinder known as swirl and tumble. Good charge motion within the cylinder will produce high turbulence levels at the end of the compression stroke. As the turbulence resulting from the conversion energy of the inlet jet decays fast, the strategy is to encapsulate some of the inlet jet in the organized motions. In this work the baseline port of a 2.0 L gasoline engine was modified by inserting a tumble plate. The work was done in support of an experimental study for which a new single-cylinder research engine was set up to allow combustion system parameters to be varied in steps over an extensive range. Tumble flow was one such parameter.

This paper describes the results of a study that examined the mechanism of phased perturbation as an emissions control technique. Phased perturbation involves independently controlling the fuel delivered to each bank of a dual bank engine (or each cylinder of a single manifold engine), which allows the two banks to have an adjustable, relative Air/Fuel (A/F) perturbation phase-shift from one another. The phase shifted exhaust is then recombined to achieve a near stoichiometric mixture prior to entering a single underbody catalyst. Phase shifting the exhaust Air/Fuel ratio creates a situation in which both rich exhaust constituents (unburnt hydrocarbons and carbon monoxide) and lean exhaust constituents (oxygen and oxides of nitrogen) arrive at the catalyst at the same time. The results of the study showed that phased perturbation produced a significant effect on A/F control and catalyst THC, CO, and NOx efficiency.

The design of helical Intake ports for swirl generation is a process that has been developed over a number of years through primarily empirical methods. A number of design rules have been established that enable designers to develop ports that approach the state-of-the-art for maximum swirl generation with minimum pressure loss. More recently, computer-aided design (CAD) tools have been introduced that permit geometry and features to be accurately defined by mathematical surface descriptions, and to be parameterized such that derived geometry is updated automatically along with parent features. The author has developed a parametric design approach for helical ports that incorporates the lessons learned from experience into a systematic design procedure. This procedure takes advantage of the current CAD capabilities to expedite the design process and improve the result.

SCR-on-filter, or SCRoF, is an emerging technology for different market segments and vehicle applications. The technology enables simultaneous particulate matter trapping and NOX reduction, and provides thermal management and aftertreatment packaging benefits. However, there is little information detailing the lubricant derived exposure effects on functional SCR performance. A study was conducted to evaluate the impact of various oil consumption pathways on a light duty DOC and SCRoF aftertreatment system. This aftertreatment system was aged utilizing an engine test bench modified to enable increased oil consumption rates via three unique oil consumption pathways. The components were characterized for functional SCR performance, ash morphology, and ash deposition characteristics. This included utilizing techniques, such as SEM / EDS, to evaluate the ash structures and quantify the ash elemental composition.

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.

Recent internal research performed at SwRI examined an emissions control mechanism that we have labeled, ‘phased A/F perturbation.’ The suggested mechanism of phased perturbation involves independently controlling the fuel delivered to each bank of a dual bank engine, which allows the two banks to have an adjustable, relative A/F perturbation phase-shift from one another. Exhaust from the two banks can be combined to achieve a near-stoichiometric mixture prior to entering a single underbody catalyst. Since both rich and lean exhaust species would be present simultaneously, a highly reactive mixture would continuously enter the catalyst. In that work, it was found that A/F phasing produced as significant an effect on conversion efficiency as perturbation amplitude and frequency, i.e. A/F phasing was identified as a third dimension for optimization of exhaust gas composition as it enters the catalyst.

Fuel conservationists will welcome this practicable proposal for converting railroads from diesel fuel to propane gas propulsion. Propane is no newcomer to the fuel family, but the advantages of economy, simplicity of operation, minimal maintenance, and extended life of equipment, as presented in this paper, show up its unexploited and extensive potential use in all mobile units. This careful study includes experimental results and data especially applied to railroad engines, even to conversion plans for existing engines that allows an interchangeable fuel system to accommodate present supply and variable cost factors in the United States.

The United States and Europe are mandating increasingly severe diesel fuel specifications, particularly with respect to sulfur content, and in some areas, aromatics content. This trend is directed towards reducing vehicle exhaust emissions and is generally beneficial to fuel quality, ignition ratings, and stability. However, laboratory studies, as well as recent field experience in Sweden and the United States, indicate a possible reduction in the ability of fuels to lubricate sliding components within the fuel injection system. These factors, combined with the trend toward increasing injection pressure in modern engine design, are likely to result in reduced durability and failure of the equipment to meet long-term emissions compliance. The U.S. Army Belvoir Fuels and Lubricants Research Facility (BFLRF) located at Southwest Research Institute (SwRI) developed an accelerated wear test that predicts the effects of fuel lubricity on injection system durability.

An experimental sensor array that measures dynamic exhaust temperature and dynamic smoke for the purpose of diagnosing diesel engine fuel injection equipment was designed, built, and tested. The sensor array is portable and easily installed on truck tailpipes, and was tested using two 6V-53 Detroit Diesel engines. The dynamic temperature sensor is a very high response instrument capable of measuring changes in gas temperature in excess of 104°F/second. The dynamic smokemeter is an optical device designed to measure very low levels of light opacity in the smoke plume, with a response compatible with the engine firing frequency. Dynamic exhaust temperature data had more diagnostic significance than dynamic smoke in the detection of maximum power degrading fuel injection faults.

Development of a state of the art, electronically controlled natural gas-fueled engine is detailed in this paper. The engine is a lean burn, turbochargedaftercooled engine controlled by a full authority electronic control system. This system controls fuel metering, spark timing, boost pressure, throttle position, and governing. The control system features closed-loop/adaptive-learn fuel control with feedback provided by a universal exhaust gas oxygen sensor. The development of the engine included development of the control system and other engine components, as well as a substantial amount of steady-state and transient control system calibration work. This effort led to a final engine calibration which provides good efficiency and transient response while meeting CARB ULEV emissions levels.

The measurement of piston temperature in a reciprocating engine has historically been a very time-consuming and expensive process. Several conditions exist in an engine that measurement equipment must be protected against. Acceleration forces near 2000 G's occur at TDC in automotive engines at rated speed. Operating temperatures inside the crankcase can range to near 150°C. To allow complete mapping of piston temperature, several measuring locations are required in the piston and data must be obtained at various engine operating conditions. Southwest Research Institute (SwRI) has developed a telemetry-based system that withstands the harsh environments mentioned above. The device is attached to the underside of a piston and temperature data is transmitted to a receiving antenna in the engine crankcase. The key element of this device is a tiny power generator which utilizes the reciprocating motion of the piston to generate electricity thus allowing the transmitter to be self-powered.

U.S. Army arctic engine oil, MIL-L-46167B, designated OEA, provides excellent low-temperature operation and is multi functional. It is suitable for crankcase lubrication of reciprocating internal combustion engines and for power-transmission fluid applications in ground equipment. However, this product required 22-percent derated conditions in the two-cycle diesel engine qualifications test. Overall, OEA oil was limited to a maximum ambient temperature use of 5°C for crankcase applications. The technical feasibility of developing an improved, multi functional arctic engine oil for U.S. military ground mobility equipment was investigated. The concept was proven feasible, and the new oil, designated as OEA-30, has exceptional two-cycle diesel engine performance at full engine output and can be operated beyond the 5°C maximum ambient temperature limit of the MIL-L-46167B product.

Impending emissions regulations for diesel engines, specifically exhaust particulate emissions have caused engine manufacturers to once again examine the potential of alternative fuels. Much interest has centered around compressed natural gas (CNG) due to its potential for low particulate and NOx emissions. Natural gas engine development projects have tended toward the use of current gasoline engine technology (stoichiometric mixtures, closed-loop fuel control, exhaust catalysts) or have applied the results of previous research in lean-burn gasoline engines (high-turbulence combustion chambers). These technologies may be inappropriate for foreseeable emissions targets in heavy-duty natural gas engines.

The principles of the magnetic-perturbation method of flaw detection and the Barkhausen noise residual stress measurement method are briefly reviewed. It is suggested that they provide very powerful tools for assuring improved ball bearing performance. The methods are applied for the evaluation of ball bearing races. Typical experimental results are presented along with metallurgical sectioning correlation.