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This collection is a resource for studying the history of the evolving technologies that have contributed to snowmobiles becoming cleaner and quieter machines. Papers address design for a snowmobile using the EPA test procedure and standard for off-road vehicles, along with more stringent U.S. National Park Best Available Technology (BAT) standards that are likened to those of the California Air Resourced Board (CARB). Innovative technology solutions include: • Standard application for diesel engine designs • Applications to address and test both engine and track noise • Benefits of the Miller cycle and turbocharging The SAE International Clean Snowmobile Challenge (CSC) program is an engineering design competition. The program provides undergraduate and graduate students the opportunity to enhance their engineering design and project management skills by reengineering a snowmobile to reduce emissions and noise.

This collection is a resource for studying the history of the evolving technologies that have contributed to snowmobiles becoming cleaner and quieter machines. Papers address design for a snowmobile using the EPA test procedure and standard for off-road vehicles. Innovative technology solutions include: • Engine Design: improving the two-stroke, gas direct injection (GDI) engine • Applications of new muffler designs and a catalytic converter • Solving flex-fuel design and engine power problems The SAE International Clean Snowmobile Challenge (CSC) program is an engineering design competition. The program provides undergraduate and graduate students the opportunity to enhance their engineering design and project management skills by reengineering a snowmobile to reduce emissions and noise. The competition includes internal combustion engine categories that address both gasoline and diesel, as well as the zero emissions category in which range and draw bar performance are measured.

Two modern light-duty passenger vehicles were selected for chassis dynamometer testing to evaluate differences in performance end efficiency resulting from CNG and gasoline combustion in a vehicle-based context. The vehicles were chosen to be as similar as possible apart from fuel type, sharing similar test weights and identical driveline configurations. Both vehicles were tested over several chassis dynamometer driving cycles, where it was found that the CNG vehicle exhibited 3-9% lower fuel economy than the gasoline-fueled subject. Performance tests were also conducted, where the CNG vehicle's lower tractive effort capability and longer acceleration times were consistent with the lower rated torque and power of its engine as compared to the gasoline model. The vehicles were also tested using quasi-steady-state chassis dynamometer techniques, wherein a series of engine operating points were studied.

Vehicle operation during cold-start powertrain conditions can have a significant impact on drivability, fuel economy and tailpipe emissions in modern passenger vehicles. As efforts continue to maximize fuel economy in passenger vehicles, considerable engineering resources are being spent in order to reduce the consumption penalties incurred shortly after engine start and during powertrain warmup while maintaining suitably low levels of tailpipe emissions. Engine downsizing, advanced transmissions and hybrid-electric architecture can each have an appreciable effect on cold-start strategy and its impact on fuel economy. This work seeks to explore the cold-start strategy of several passenger vehicles with different powertrain architectures and to understand the resulting fuel economy impact relative to warm powertrain operation. To this end, four vehicles were chosen with different powertrain architectures.

Aluminum based brake rotors have been a priority research topic in the DOE 1999 Aluminum Industry Roadmap for the Automobile Market. After fourteen years, no satisfactory technology has been developed to solve the problem of aluminum's low working temperatures except the steel clad aluminum (SCA) brake technology. This technology research started at Michigan Technological University (MTU) in 2001 and has matured recently for commercial productions. The SCA brake rotor has a solid body and replaces the traditional convective cooling of a vented rotor with conductive cooling to a connected aluminum wheel. Much lower temperatures result with the aluminum wheel acting as a great heat sink/radiator. The steel cladding further increases the capability of the SCA rotor to withstand higher surface temperatures. During the road tests of SCA rotors on three cars, significant gas mileage improvement was found; primarily attributed to the unique capability of the SCA rotor on pad drag reduction.

Hydrotreated vegetable oil (HVO) is a high-cetane number alternative fuel with the potential of drastic emissions reductions in high-pressure diesel engines. In this study the behavior of HVO sprays is investigated computationally and compared with conventional diesel fuel sprays. The simulations are performed with a modified version of the C++ open source code OpenFOAM using Reynolds-averaged conservation equations for mass, species, momentum and energy. The turbulence has been modeled with a modified version of the RNG k-ε model. In particular, the turbulence interaction between the droplets and the gas has been accounted for by introducing appropriate source terms in the turbulence model equations. The spray simulations reflect the setup of the constant-volume combustion cell from which the experimental data were obtained.

A modified version of the Laminar and Turbulent Characteristic Time combustion model and the Hiroyasu-Magnussen soot model have been implemented in the flow solver Star-CD. Combustion simulations of three DI diesel engines, utilizing the standard k-ε turbulence model and a modified version of the RNG k-ε turbulence model, have been performed and evaluated with respect to combustion performance and emissions. Adjustments of the turbulent characteristic combustion time coefficient, which were necessary to match the experimental cylinder peak pressures of the different engines, have been justified in terms of non-equilibrium turbulence considerations. The results confirm the existence of a correlation between the integral length scale and the turbulent time scale. This correlation can be used to predict the combustion time scale in different engines.

In sheet metal forming, metal flow into the die is determined by the restraint imposed by both the blankholder force and the drawbead penetration. This paper describes an experimental investigation in which both advanced binder force and drawbead technologies are used to study their effect on draw depth in the drawing of an AA6111-T4 generic non-symmetric panel. Multipoint binder loading using individual pin force adjustment applied to especially designed binder structures as well as the use of variable blankholder force were investigated in one laboratory in Germany. In another laboratory in the USA, active drawbeads were applied to the drawing of the generic panel. The results of both approaches, which are shown to be successful, are presented and discussed.

The Vehicle Engine Cooling System Simulation (VECSS) computer code has been developed at the Michigan Technological University to simulate the thermal response of a cooling system for an on-highway heavy duty diesel powered truck under steady and transient operation. In Part 1 of this research, the code development and verification has been presented. The revised and enhanced VECSS (version 8.1) software is capable of simulating in real-time a Freightliner FLD 120 truck with a Detroit Diesel Series 60 engine, Behr McCord radiator, Allied signal / Garrett Automotive charge air cooler and turbocharger, Kysor DST variable speed fan clutch, DDC oil and coolant thermostat. Other cooling system components were run and compared with experimental data provided by Kysor Cooling Systems. The experimental data were collected using the Detroit Diesel Electronic Control's (DDEC) Electronic Control Module (ECM) and the Hewlett Packard (HP) data acquisition system.

Up to 80 percent of the total hydrocarbons emitted during the EPA Federal emissions test are produced in the first five minutes of this procedure. It has been theorized that this is in part due to wall wetting of the intake port and cylinder. This study measures the behavior of the fuel film thickness in the intake port during cold starting, steady state and transient operation. Three injector spray patterns with varying droplet sizes were utilized for the tests. The fuel film thickness in the intake port of a Ford 1.9L engine was measured using optical sensors. It was found that the spray pattern and droplet size affected the port wall wetting characteristics.

A computer simulation model to predict the thermal responses of an on-highway heavy duty diesel truck in transient operation was used to study several important cooling system design and operating variables. The truck used in this study was an International Harvester COF-9670 cab-over-chassis vehicle equipped with a McCord radiator, Cummins NTC-350 diesel engine, Kysor fan-clutch and shutter system, aftercooler, and standard cab heater and cooling system components. Input data from several portions of a Columbus to Bloomington, Indiana route were used from the Vehicle Mission Simulation (VMS) program to determine engine and vehicle operating conditions for the computer simulation model. The thermostat-fan, thermostat-shutter-fan, and thermostat-winterfront-fan systems were studied.

A set of control functions have been investigated for a computer controlled diesel cooling system, using the vehicle engine cooling system code. Various engine operating conditions such as the engine load, engine speed, and ambient temperature are considered as the controlling variables in the control loops. The truck simulated in the study was an International Harvester COF-9670 cab over chassis heavy-duty vehicle equipped with a standard cab heater, a Cummins NTC-350 diesel engine with a McCord radiator and standard cooling system components and after-cooler. The vehicle also had a Kysor fan-clutch and shutter system. Comparison simulation tests between the conventional cooling system and the computer controlled cooling system using the Vehicle-Engine-Cooling Computer System model under different ambient and route conditions show that the computer controlled cooling system would offer the following benefits: 1.

Twenty vehicles from eighteen schools competed in the Second SAE Super Mileage Competition at the Eaton Proving Grounds, Marshall, Michigan, on June 6, 1981. Of these, fifteen completed all of the events with the winner obtaining 702 miles/gallon (298.4 KM/liter). The designs of the successful vehicles were quite varied but stressed lightness, aerodynamic streamlining, low rolling resistance and efficient drive trains. Some engines were also modified- to improve efficiency. The integrated optimization of all variables within the severe constraints of budget, manpower, time and manufacturing facilities presented an excellent engineering experience for the students.