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Forty-five cars were entered from 37 universities across the U.S. and Canada in the ninth annual Formula SAE Student Design Competition held on May 25, 26 and 27 at the University of Texas at San Antonio (UTSA). Thirty-six cars from 31 schools actually competed, but only 22 cars finished. The event included many firsts in Formula SAE. The SAE South Texas Section set a precedent by co-hosting the competition with the UTSA. The GM Sunraycer display and demonstration exhibited high technology and corporate support of Formula SAE. Total award funds (from various sponsors) exceeded those of previous events. New awards were given by new sponsors in 1989.

This paper will describe the fuel economy benefits that can be obtained when traditionally engine-driven accessories such as water pumps, oil pumps, power steering pumps, radiator cooling fans and air conditioning compressors are decoupled from the engine and are remotely driven and controlled. Simulation results for different vehicle configurations such as heavy duty trucks operated over urban and highway driving cycles and light duty vehicles such as mini vans will be presented. These results will quantify the heavy dependence of fuel economy benefits associated with different types of driving cycles.

A vehicle's gasoline fuel tank was removed and replaced with a 5,000-psig, Type-III, aluminum-lined hydrogen cylinder. High-pressure cylinders are typically installed with a thermally-activated pressure relief device (PRD) designed to safely vent the contents of the cylinder in the event of accidental exposure to fire. The objective of this research was to assess the results of a catastrophic failure in the event that a PRD were ineffective. Therefore, no PRD was installed on the vehicle to ensure cylinder failure would occur. The cylinder was pressurized and exposed to a propane bonfire in order to simulate the occurrence of a gasoline pool fire on the underside of the vehicle. Measurements included temperature and carbon monoxide concentration inside the passenger compartment of the vehicle to evaluate tenability. Measurements on the exterior of the vehicle included blast wave pressures. Documentation included standard, infrared, and high-speed video.

Radioactive tracer technology (RATT™) is an important tool for measuring real-time wear in operating engines and other mechanical systems. The use of this technology provides important wear information that is not available by other, more conventional wear measurement methods. The technology has advanced to the point where several components can be interrogated simultaneously, and new methods have extended the method to materials that are normally not amenable to radioactive tracer evaluation. In addition, sensitivity has increased so that the onset of wear can be detected long before practical with non-tracer methods. This improves the ability to measure and determine cause and effect relationships, thus providing a better understanding of wear responses to specific operating conditions and to changes in operating conditions. This paper reviews the radioactive tracer process and recent improvements that have extended its reach in both automotive and non-automotive applications.

This paper describes algorithms that can recognize and track the engine crankshaft position for arbitrary cam- and crank-shaft tooth wheel patterns in both steady-state and transient operating conditions. Crankshaft position tracking resolution is adjustable to accommodate different application requirements. The instantaneous crankshaft position information provided by the position tracking module form the basis for crankshaft angle domain (CAD) engine control and measurement functions such as precise injection / ignition controls and on-line cylinder pressure CAD analyses. The algorithms described make reconfiguration of the tracking module for different and arbitrary cam- and crank-shaft tooth wheel patterns very easy, which is valuable especially for prototyping engine control systems. The effectiveness of the algorithms is shown using test engines with different cam and crank signal patterns.

An electromagnetic valve actuation (EVA) system was developed and applied to a Kohler Command Series engine. Engine development and testing was conducted for the purpose of evaluating the performance of the EVA-equipped engine, running on natural gas, in an engine-test laboratory environment. As part of this effort, a personal computer-based engine control system, which managed the fueling, ignition, throttling, and intake/exhaust valve control functions, was developed. The evaluation included an investigation into increasing engine power output and full load efficiency, as well as increased part load efficiency. Techniques including optimized valve events as a function of operating condition, and throttleless operation using early and late intake valve closing are presented. Engine simulation results are compared with actual engine data and presented in this paper.

A system for injection of diesel fuel and water with real-time control, or real-time water injection (RTWI), was developed and applied to a heavy-duty diesel engine. The RTWI system featured electronic unit pumps that delivered metered volumes of water to electronic unit injectors (EUI) modified to incorporate the water addition passages. The water and diesel mixed in the injector tip such that the initial portion of the injection contained mostly diesel fuel, while the balance of the injection was a water and diesel mixture. With this hardware, real-time cycle-by-cycle control of water mass was used to mitigate soot formation during diesel combustion. Using RTWI alone, NOx emissions were reduced by 42%. Using high-pressure-loop exhaust gas recirculation (EGR) and conventional diesel combustion with RTWI, the NOx was reduced by 82%.

The engine selected for this work was a Caterpillar 3176 engine. Engine exhaust emissions, performance, and heat release rates were measured as functions of engine configuration, engine speed and load. Two engine configurations were used, a standard 1994 design and a 1994 configuration with EGR designed to achieve a NOx emissions level of 2.5 gm/hp-hr. Measurements were performed at 7 different steady-state, speed-load conditions on thirteen different test fuels. The fuel matrix was statistically designed to independently examine the effects of the targeted fuel properties. Cetane number was varied from 40 to 55, using both natural cetane number and cetane percent improver additives. Aromatic content ranged from 10 to 30 percent in two different forms, one in which the aromatics were predominantly mono-aromatic species and the other, where a significant fraction of the aromatics were either di- or tri-aromatics.

Brake energy recovery is one of the key components in today's hybrid vehicles that allows for increased fuel economy. Typically, major engineering changes are required in the drivetrain to achieve these gains. The objective of this paper is to present a concept of capturing brake energy in a mild hybrid approach without any major modifications to the drivetrain or other vehicular systems. With fuel costs rising, the additional component cost incurred in the presented concept may be recovered quickly. In today's vehicles, alternators supply the electrical power for the engine and vehicle accessories whenever the engine is running. As vehicle electrical demands increase, this load is an ever-increasing part of the engine's output, negatively impacting fuel economy. By using a regenerative device (alternator) on the drive shaft (or any other part of the power train), electrical energy can be captured during braking.

A novel urea evaporation and mixing device has been developed to improve the overall performance of a urea-SCR system. The device was tested with a MY2007 Cummins ISB 6.7L diesel engine equipped with an SCR aftertreatment system. Test results show that the device effectively improved the overall NO conversion efficiency of the SCR catalyst over both steady-state and transient engine operating conditions, while NH₃ slip from the catalyst decreased.

The VanDyne SuperTurbocharger (SuperTurbo) is a turbocharger with an integral Continuously Variable Transmission (CVT). By changing the gear ratio of the CVT, the SuperTurbo is able to either pull power from the crankshaft to provide a supercharging function, or to function as a turbo-compounder, where energy is taken from the turbine and given to the crankshaft. The SuperTurbo's supercharger function enhances the transient response of a downsized and turbocharged engine, and the turbo-compounding function offers the opportunity to extract the available exhaust energy from the turbine rather than opening a waste gate. Using 1-D simulation, it was shown that a 2.0-liter L4 could exceed the torque curve of a 3.2L V6 using a SuperTurbo, and meet the torque curve of a 4.2-liter V8 with a SuperTurbo and a fresh-air bypass configuration. In each case, the part-load efficiency while using the SuperTurbo was better than the baseline engine.

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 ].

Hybrid hydraulic power trains are a natural fit for heavy duty vehicle applications due to their high power density. This paper describes the analytical formulae available for sizing a series hybrid hydraulic vehicle without changing the engine size. Sizing of pump, accumulator and motor are addressed specifically. A control strategy is also suggested for operating the engine and powertrain pressure close to the best efficiency zones. An example is then given using an FMTV (Family of Medium Tactical Vehicles) platform with a CAT C7 engine. Simulation results are generated using VPSET (Vehicle Propulsion Systems Evaluation Tool), an SwRI-developed vehicle modeling and simulation tool. The hydraulic components are sized according to the recommendations in this paper. The suggested control strategy is implemented in VPSET and performance of the series hydraulic hybrid configuration is compared with that of a conventional powertrain.

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.

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.

Increasing fuel costs and the desire for reduced dependence on foreign oil has brought the diesel engine to the forefront of future medium-duty vehicle applications in the United States due to its higher thermal efficiency and superior durability. The main obstacle to the increased use of diesel engines in this platform is the upcoming extremely stringent, Tier 2 emission standard. In order to succeed, diesel vehicles must comply with emissions standards while maintaining their excellent fuel economy. The availability of technologies such as common rail fuel injection systems, low sulfur diesel fuel, NOX adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with these future requirements. In meeting the Tier 2 emissions standards, the heavy light-duty trucks (HLDTs) and medium-duty passenger vehicles (MDPVs) will face the greatest technological challenges. In support of this, the U.S.

In-cylinder ion sensing through sparkplug electrodes can be used to determine in-cylinder A/F ratio by using a modified production coil-on-plug ignition system having ion sensing capability. The in-cylinder ionization can be characterized by the height of the peak, location of the peak from ignition command and area under the ionization signal curve. The effects of A/F ratio on the in-cylinder ionization can be isolated from other affecting factors by conducting tests on a constant volume combustion device in which the initial pressure and temperature can be well controlled. This results in a parabolic correlation of the ionization characteristics with the mixture equivalence ratio. Additionally the ionization characteristics show strong dependence on engine load and speed. Equivalence ratio characteristics during engine cranking and warm up are investigated, and a method for on-line calibration of ionization detection is discussed.

A technique was developed for measuring the Laminar Burning Velocity (LBV) of multi-component fuel blends for use in high-performance spark-ignition engines. This technique involves the use of a centrally-ignited spherical combustion chamber, and a complementary analysis code. The technique was validated by examining several single-component fuels, and the computational procedure was extended to handle multi-component fuels without requiring detailed knowledge of their chemical composition. Experiments performed on an instrumented high-speed engine showed good agreement between the observed heat-release rates of the fuels and their predicted ranking based on the measured LBV parameters.

The Partnership for a New Generation Vehicle (PNGV) has identified the compression-ignition, direct-injection (CIDI) engine as a promising technology in meeting the PNGV goal of 80 miles per gallon for a prototype mid-size sedan by 2004. Challenges remain in reducing the emission levels of the CIDI-engine to meet future emission standards. The objective of this project was to perform an initial screening of crank case lubricant contribution to regulated engine-out emissions, particularly when low particulate forming diesel fuel formulations are used. The test engine was the Mercedes-Benz OM611, the test oils were a mineral SAE 5W30, a synthetic (PAO based) SAE 5W30, and a synthetic (PAO based) SAE 15W50, and the test fuels were a California-like certification fuel and an alternative oxygenated diesel fuel.

The Tank-Automotive RD&E Center periodically conducts foreign materiel evaluations to assess the current state of the art for ground vehicle technologies. The Propulsion Laboratory is conducting performance evaluations of an opposed-piston two-stroke diesel tank engine produced by the Kharkov Design Bureau in Ukraine. A key factor in the performance of all two-stroke engines is the scavenging process, which determines how well the cylinders are emptied of exhaust and filled with fresh air. The overall air flow rate is not sufficient to determine this, as a significant amount of air may be lost through the exhaust ports during the scavenging process. The inlet tracer gas method was employed to provide the additional data required. With methane as the tracer, it produced reasonable and consistent data over a wide range of engine speeds and loads. The inlet tracer gas method was found to be an effective tool for measuring the scavenging performance of a running two-stroke diesel engine.