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The University of Idaho has sponsored entries in the Collegiate Design Series (CDS) Clean Snowmobile Competition since 2001. During this period, a topic of ongoing concern among its student leaders is project and knowledge management. The need for holistic implementation of specific methods/tools is underscored by survey feedback from current CDS teams and University of Idaho alumni, many now employed in the automotive/motorsports industry. This paper details local implementation of nine developmentally appropriate practices for CDS teams composed of students at multiple levels in their academic study (underclassmen, seniors, and graduate students).

There is insufficient time within a single technical elective to learn principles of internal combustion engine operation as well as specialized simulation tools such as GT Suite or Kiva. A number of authors have recognized this constraint, and they have structured their internal combustion engine text around use of programming languages such as FORTRAN, C++, and MATLAB®. This paper reports on how the capabilities of MATLAB® have been synergized with learning activities and homework assignments to set the stage for a successful final engine simulation project. The MATLAB® code involved in this effort can accept basic input parameters such as bore, stroke, compression ratio, spark advance, throttle position, RPM, air/fuel equivalence ratio, and volumetric efficiency. The code returns output power and torque using the Wiebe function and bulk temperature. The model uses a two-zone heat release model to predict power, torque, brake specific fuel consumption, and volumetric emissions.

Over the last five years the Vandal Hybrid Racing team at the University of Idaho has developed a compact, lightweight, and mass centralized vehicle design with a rule-based energy management system. Major areas of innovation are a close fitting frame design made possible by the location of major components and engine modifications to improve performance. The innovative design features include a custom designed engine, battery pack and simplistic hybrid coupling system. The vehicle also incorporates a trailing link suspension, and realization of a rule-based Energy Management System (EMS) which determines the power split of the combustion and electric systems. The EMS oversees the operation of the Lynch electric motor and the YZ250F engine that is housed in a custom crankcase. The battery pack can initially store 2 MJ of energy in a single 50 lb. lithium polymer battery pack that is located underneath the cockpit.

This paper details a multiyear effort at the University of Idaho to develop a very compact powertrain that results in a lower center of gravity and smaller pitch and yaw inertia for a single-seat open-wheeled hybrid competition vehicle. This design entails introducing torque from the electric motor to the countershaft of a Yamaha YZ250F engine, allowing torque multiplication via the transmission and thus to the final drive and wheels. Maximum motor speed into the countershaft corresponds to maximum speed of the engine. The repackaged powertrain features a D135RAG Lynch electric motor connected to a customized countershaft that is housed in a machined aluminum case that includes Original Equipment Manufacturer (OEM) engine and transmission internals. This case also incorporates a Torsen differential with an in-house designed planetary gear reduction.

As part of its single-fuel initiative, the US Armed Forces has a desire to operate all of their equipment on JP-8 fuel. Larger applications using diesel engines have been easy to convert, but small gasoline engine conversions have proven more difficult. This paper chronicles problems encountered, successful solutions, and lessons learned during the conversion of a carbureted 2kW Honda generator for use with JP-8 fuel. Cold-start, fuel delivery, load control, and auxiliary systems required significant adaptation. A catalytic plasma torch was used as the ignition source and similar technology was developed to support cold-starting at temperatures down to -40°C. Combustion chamber design and low octane number fuel made it necessary for multiple ignition sources. Load control and auxiliary systems were handled by a custom micro-controller that used RPM, generator output current, head temperature, and a knock sensor as inputs.

In order to satisfy the single-fuel initiative, the US Armed Forces have need of man-portable electrical generation that will operate on JP-8 fuel. Previous conversions use diesel engines, which tend to be large and heavy - partially due to the high compression ratios necessary. This research shows the conversion process and performance of a low compression ratio gasoline genset for JP-8 operation. Central to this conversion was a catalytic plasma torch that replaces the conventional spark plug, and slight modifications to the fuel system. Comparisons between the stock gasoline genset and modified JP-8 genset are given for: power output, emissions, fuel flow, and efficiency. The tests were conducted in a cold chamber under 25 °C, 4 °C, and -10 °C conditions. The JP-8 conversion added minimal weight to the genset that can be started by hand with a pull cord.

Acoustical tuning of intake manifolds is a common practice used to achieve gains in volumetric efficiency in a pre-determined region on the torque curve. Many methods exist for acoustical tuning of the intake including a variation of the Helmholtz resonator model by Engelman as well as the organ pipe models by Ricardo and Platner. In this work a new intake tuning model has been developed using an Impedance Transform Model along with a minimal set of limiting assumptions. Unlike the models of Engelman and Platner, this model can accommodate any intake geometry. The model can also be used to analyze specific points in the intake system or the entire system rather than just the intake runners. Model verification consisted of resonance testing of three different Helmholtz resonators as well as dynamometer testing of a Honda CBR F3 four-stroke SI engine using three different intake system geometries.

Lean ethanol-water/air mixtures have potential for reducing NOx and CO emissions in internal combustion engines. Igniting such mixtures is not possible with conventional ignition sources. An improved catalytic ignition source is being developed to aid in the combustion of aqueous ethanol. The operating principle is homogeneous charge compression ignition in a catalytic pre-chamber, followed by torch ignition of the main chamber. In this system, ignition timing can be adjusted by changing the length of the catalytic core element, the length of the pre-chamber, the diameter of the pre-chamber, and the electrical power supplied to the catalytic core element. A multi-zone energy balance model has been developed to understand ignition timing of ethanol-water mixtures. Model predictions agree with pressure versus crank angle data obtained from a 15 kW Yanmar diesel engine converted for catalytic operation on ethanol-water fuel.