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Kettering University's entry for the 2006 Clean Snowmobile challenge utilizes a Polaris FST Switchback. This snowmobile having a two cylinder, four-stroke engine has been modified to run on ethanol (E-85). The student team has designed and built a new exhaust system which features customized catalytic converters to minimize engine out emissions. A number of improvements have been made to the track to reduce friction and diminish noise.

Clean snowmobile technology has been developed using methods which can be applied in the real world with a minimal increase in cost. Specifically, a commercially available snowmobile using a two cylinder, four-stroke engine has been modified to run on high-blend ethanol (E-85) fuel. Additionally, a new exhaust system which features customized catalytic converters and mufflers to minimize engine noise and exhaust emissions has developed. Finally, a number of additional improvements have been made to the track to reduce friction and diminish noise. The results of these efforts include emissions reductions of 94% when compared with snowmobiles operating at the 2012 U.S. Federal requirements.

Numerical simulations of lean Methanol combustion in a four-stroke internal combustion engine were conducted on a high-compression ratio engine. The engine had a removable integral injector ignition source insert that allowed changing the head dome volume, and the location of the spark plug relative to the fuel injector. It had two intake valves and two exhaust ports. The intake ports were designed so the airflow into the engine exhibited no tumble or swirl motions in the cylinder. Three different engine configurations were considered: One configuration had a flat head and piston, and the other two had a hemispherical combustion chamber in the cylinder head and a hemispherical bowl in the piston, with different volumes. The relative equivalence ratio (Lambda), injection timing and ignition timing were varied to determine the operating range for each configuration. Lambda (λ) values from 1.5 to 2.75 were considered.

Impinging jets are an established technique for obtaining high local heat transfer coefficients between a fluid and a surface. Factors such as jet attachment, surface angle, jet angle, separation distance between jet orifice and surface of impingement, and trajectory influence heat transfer dramatically. In the current study, the specific application of interest is air issuing from the defroster's nozzles of a vehicle and impinging on a glass windshield. The current work is aimed at studying the flow patterns off a vehicle windshield as a result of air issuing from various nozzle configurations. The effects of openings' geometry (circular vs rectangular), number of openings, angle that the windshield makes with the horizontal plane and angle of impinging jet, on windshield heat transfer is examined. An optimal configuration will be recommended for better heat transfer.

A numerical study on the combustion of Methanol in a directly injected (DI) engine was conducted. The study considers the effect of the bowl-in-piston (BIP) geometry, swirl ratio (SR), and relative equivalence ratio (λ), on flame propagation and burn rate of Methanol in a 4-stroke engine. Ignition-assist in this engine was accomplished by a spark plug system. Numerical simulations of two different BIP geometries were considered. Combustion characteristics of Methanol under swirl and no-swirl conditions were investigated. In addition, the amount of injected fuel was varied in order to determine the effect of stoichiometry on combustion. Only the compression and expansion strokes were simulated. The results show that fuel-air mixing, combustion, and flame propagation was significantly enhanced when swirl was turned on. This resulted in a higher peak pressure in the cylinder, and more heat loss through the cylinder walls.

A dimensionless relationship that estimates the maximum bearing load of a 4-cylinder 4-stroke in-line engine has been found. This relationship may assist the design engineer in choosing a desired counterweight mass. It has been demonstrated that: 1) the average bearing load increases with engine speed and 2) the maximum bearing load initially decreases with engine speed, reaches a minimum, then increases quickly with engine speed. This minimum refers to a transition speed at which the contribution of the inertia force overcomes the contribution of the maximum pressure force to the maximum bearing load. The transition speed increases with an increase of counterweight mass and is a function of maximum cylinder pressure and the operating parameters of the engine.

A numerical and experimental study of the use of air motion control, piston bowl shape, and injector configuration on combustion and emissions in diesel engines has been conducted. The objective of this study is to investigate the use of flow control within the piston bowl during compression to enhance fuel air mixing to achieve a uniform air-fuel mixture to reduce soot and NO emissions. In addition to flow control different piston bowl geometries and injector spray angles have been considered and simulated using three-dimensional computational fluid dynamics and experiments. The results include cylinder pressure and emissions measurements and contour plots of fuel mass fraction, soot, and NO. The results show that soot and NO emissions can be reduced by proper flow control and piston bowl design.

A coupler has been developed to prevent windshield wiper systems from being damaged by excessive loads that can occur when the normal wiping pattern is restricted. The coupler is composed of a pultruded composite rod with injection-molded plastic spherical joints (a.k.a. sockets) attached at either end. The sockets are used to attach the coupler to the crank and rocker of the windshield wiper linkage. Because the loads exerted on a coupler vary in magnitude and direction during a wiping cycle, the joint between the sockets and the pultruded composite rod must be robust. The paradigm for attaching sockets to steel couplers (i.e. over-molding the sockets around holes stamped into the ends of traditional steel couplers) was applied to the pultruded rods, tested, and found to produce inadequate joint strength. This paper details the methodology that was employed to produce and optimize an acceptable means to attach the injection-molded sockets to the pultruded rods.

Large hood mounted plastic trim components are subjected to complex and often extreme loading conditions. Typical loading conditions include solar and thermal cycling, as well as road and powertrain induced vibrations, aero lift and buffeting, and mechanical loads such as car wash. For the above components understanding and classifying the typical loading conditions is an essential and important step in achieving long term quality. This paper discusses different approaches to the design, analysis, development, and testing of plastic trim components. Samples of analysis and test results are presented to demonstrate how to identify and prevent the loss of the part function. Some useful guidelines and practices for addressing thermal expansion, dimensional variation, and redundancy in attachments are also discussed.

Doors inside an automotive HVAC module are essential components to ensure occupant comfort by controlling the cabin temperature and directing the air flow. For temperature control, the function of a door is not only to close/block the airflow path via the door seal that presses against HVAC wall, but also control the amount of hot and cold airflow to maintain cabin temperature. To meet the stringent OEM sealing requirement while maintaining a cost-effective product, a “V-Shape” soft rubber seal is commonly used. However, in certain conditions when the door is in the position other than closed which creates a small gap, this “V-Shape” seal is susceptible to the generation of objectionable whistle noise for the vehicle passengers. This nuisance can easily reduce end-customer satisfaction to the overall HVAC performance.

Kettering University's Clean Snowmobile Challenge student design team has developed a new robust and innovative snowmobile for the 2004 competition. Switching from the previous years four-stroke automotive engine, Kettering University has utilized a modified snowmobile in-line four cylinder, four-stroke, fuel- injected engine. This engine has been installed into a 2003 Yamaha RX-1 snowmobile chassis. Exhaust emissions have been minimized through the use of a customized catalytic converter and an electronically controlled closed-loop fuel injection system. A newly designed and tuned exhaust as well as several chassis treatments have aided in minimizing noise emissions.

The combustion process in an IC engine is of significant importance for its noise and vibration characteristics in the vehicle. Describing the combustion process with thermodynamic metrics typically demands extensive instrumentation of the engine to obtain the cylinder pressure from the combustion chamber. This time consuming task often requires, that the engine be removed from the vehicle, instrumented with pressure transducers, and then either reinstalled in the vehicle and tested or installed in a test cell and evaluated. This paper describes a new relatively simple approach towards examining important combustion parameters. The technique is based on statistical analysis of the crankshaft's speed fluctuation. This approach requires relatively simple instrumentation of the engine and is therefore more applicable for vehicle level investigations.

Kettering University's Clean Snowmobile Challenge student design team has developed a new robust and innovative snowmobile for the 2005 competition. This snowmobile dramatically reduces exhaust and noise emissions and improves fuel economy compared with a conventional snowmobile. Kettering University has utilized a modified snowmobile in-line four cylinder, four-stroke, engine. The team added an electronically-controlled fuel-injection system with oxygen sensor feedback to this engine. This engine has been installed into a 2003 Yamaha RX-1 snowmobile chassis. Exhaust emissions have been further minimized through the use of a customized catalytic converter and an electronically controlled closed-loop fuel injection system. A newly designed and tuned exhaust as well as several chassis treatments have aided in minimizing noise emissions.

Three-dimensional numerical simulations of a diesel-fueled engine with a pre-chamber located in the cylinder head and a bowl in the piston were performed. The study considers the effect of diesel combustion in the pre-chamber on turbulence generation and hence fuel-air mixing and combustion in the piston-bowl. Diesel fuel was injected directly into the pre-chamber and the piston bowl at different times. In order to better determine the effect of pre-chamber combustion on the main chamber combustion, various pre-chamber injection timings were considered. The results show that pre-chamber combustion caused the average cylinder pressure to increase by up to 20% in some cases.

With many advantages of GDI technology, one major disadvantage is high HC emissions. The primary goal of this study is to determine the optimum values of engine parameters that would result in maximum power output from a GDI engine, with complete combustion, minimum hydrocarbon (HC) emissions, and minimum specific fuel consumption. A two-dimensional engine geometry with a piston-bowl was selected for faster engine CFD simulations. The first part involves a study of the affect of engine parameters on performance and HC emissions. The parameters considered were, equivalence ratio (mass of injected fuel), injection timing, ignition timing, engine RPM, spray cone angle, and velocity of fuel injection. The second part of the study involves determining the optimum values of fuel mass injected, injection timing, and ignition timing in order to maximize power output while limiting the amount of fuel left unburned after the end of the expansion process.

This paper describes experiments conducted to determine the effect of multiple spark discharge ignition systems and spark plug electrode design on cold start performance of a dedicated E85 fueled vehicle. Tests were conducted using three different ignition configurations: OEM ignition and spark plugs, multiple spark discharge ignition with OEM spark plugs, and multiple spark discharge ignition with large gap circular electrode spark plugs. The multiple spark discharge ignition with OEM spark plugs showed a significant improvement in cold start performance over the OEM ignition, but the addition of the circular electrode spark plugs caused a decrease in cold start performance. The circular ground spark plugs did produce a higher ending coolant temperature than either of the other configurations.

The objective of this paper is to determine the whirling bending critical speeds of pultruded composite shafts in simply supported boundary conditions. Theoretical studies have been carried using Patran to determine the natural frequencies and the mode shapes for the Jeffcot and Kikuchi rigid rotor models. A tabletop experimental apparatus has been fabricated and the bending critical speeds have been measured for various span lengths between the supports. The results of this study may be useful in identifying whether pultruded composite shafts can be employed as drive shafts in automotive or other industries.

Cylinder air/fuel ratio distribution is an important factor affecting the economy, power, vibration, and emissions of an internal combustion engine. Currently, production automobiles utilize an exhaust gas sensor located in the main exhaust stream in order to regulate air/fuel mixtures. By measuring the oxygen content of the exhaust gas for each cylinder independently, the degree of air/fuel variation between cylinders can be determined. This information can be used to determine the mixture quality of specific cylinders. Knowing these variances can lead to design changes in the intake and exhaust manifolds as well as better control of fuel metering which will improve the output of the engine. This study was carried out using a 1991 3.8L Buick V-6 engine with customized exhaust manifolds utilizing exhaust gas oxygen sensors for each cylinder in addition to the sensor located in the main combined exhaust gas stream. Production level, ZrO2 sensors were used for this experimental study.

In automotive assembly facilities worldwide, many critical vehicle systems such as brakes, power steering, radiator, and air conditioning require the appropriate fluid to function. In order to insure that these critical vehicle systems receive the correct amount of properly treated fluid, automotive manufacturers employ a method called Evacuation and Fill. Due to their closed-loop design, many critical vehicle systems must be first exposed to vacuum prior to being flooded with fluid. Only after the evacuation and fill process is complete will the critical vehicle system be able to perform as specified. It has long been thought, but never proven, that humidity and entrenched fluid were major hindrances to the Evacuation and Fill process. Consequently, Ford Motor Company Advanced Manufacturing Technology Development, Sandalwood Enterprises, Kettering University, and Dominion Tool & Die conducted a detailed project on this subject.

This paper describes the experiments conducted to determine the effect of high energy multiple spark discharge (MSD) ignition systems and spark plug electrode design, on the cold start performance of a vehicle which was converted for dedicated operation on E85 (a blend of 85% ethanol and 15% gasoline) fuel. Tests were conducted using three different ignition configurations; original equipment manufacturer (OEM) ignition and spark plugs, high energy multiple spark discharge (MSD) ignition with OEM, J-type spark plugs, and high energy MSD ignition with surface gap electrode spark plugs. The high energy MSD ignition with OEM spark plugs showed a significant improvement in cold start performance over the OEM ignition. The addition of the surface gap spark plugs caused a decrease in cold start performance. Despite this, the surface gap spark plugs produced higher ending coolant temperature than the other configurations.