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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 E10 gasoline (10% ethanol mixed with pump gasoline). Performance technologies that are presented include: • Engine Design: application of the four-stroke engine • Applications to address both engine and track noise • Exhaust After-treatment to reduce emissions 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.

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.

Environmental awareness and fuel economy legislation has resulted in greater emphasis on developing more fuel efficient vehicles. As such, achieving fuel economy improvements has become a top priority in the automotive field. Companies are constantly investigating and developing new advanced technologies, such as hybrid electric vehicles, plug-in hybrid electric vehicles, improved turbo-charged gasoline direct injection engines, new efficient powershift transmissions, and lighter weight vehicles. In addition, significant research and development is being performed on energy management control systems that can improve fuel economy of vehicles. Another area of research for improving fuel economy and environmental awareness is based on improving the customer's driving behavior and style without significantly impacting the driver's expectations and requirements.

The National Science Foundation recently sponsored a Workshop on Environmentally Benign Manufacturing (EBM) for the Transportation Industries. The objective of the workshop was to determine future directions of research in the EBM area and to construct a roadmap for development of future research programs. While research in the fields of Design for the Environment (DfE) and Life Cycle Analysis (LCA) have focused on the product and product life cycles, an additional focus is needed to find and develop processes with less environmental impact within the manufacturing environment. This workshop explored EBM issues with respect to the enterprise, the products, the processes and the materials.

In the automotive industry, lost foam casting is a relatively new technology, which is gaining popularity among manufacturers. Lost foam casting is a process in which an expanded polystyrene pattern is formed into the shape of the part to be cast. More complex parts are fabricated by simply gluing several simple patterns together. The pattern is then coated with a refractory material consisting of a mineral mixture and binders. Finally, hot metal is poured into the pattern, evaporating the expanded polystyrene and taking shape of the coating shell. However, the automotive industry has observed that a significant number of these fabricated, coated patterns are damaged, or do not meet specifications prior to casting. These are not reusable and inevitably are landfilled. It is the goal of this project to develop a simple, reliable, and inexpensive technology to recover expanded polystyrene from the glue and coating constituents.

The use of cutting fluid in machining operations not only poses a health risk to workers but also creates environmental challenges associated with fluid treatment and disposal. In an effort to minimize these concerns and eliminate the costs associated with cutting fluids, e.g., purchase, maintenance, and treatment, dry machining is increasingly being considered as an alternative. This paper is focused on comparing dry and wet machining approaches from several perspectives, including air quality, product quality, and economics. Both experimental and analytical work is presented. Experiments have been performed to determine the effect cutting fluid has on product quality and aerosol generation in the wet and dry turning of gray cast iron. To compare costs in wet and dry turning, a cost model, which includes cutting fluid-related components, has also been established.

A thermal management system for heavy duty diesel engines is presented for maintaining acceptable and constant engine temperatures over a wide range of operational conditions. It consists of a computer controlled variable speed coolant pump, a position controlled thermostat, and a model-based control strategy. An experimentally validated, diesel engine cooling system simulation was used to demonstrate the thermal management system's capability to reduce power consumption. The controller was evaluated using a variety of operating scenarios across a wide range of loads, vehicle speeds, and ambient temperatures. Three metrics were used to assess the effects of the computer controlled system: engine temperature, energy savings, and cab temperature. The proposed control system provided very good control over the engine coolant temperatures while maintaining engine metal temperatures within a desired range.

As demand for wall-flow Diesel Particulate Filters (DPF) increases, accurate predictions of DPF behavior, and in particular their pressure drop, under a wide range of operating conditions bears significant engineering applications. In this work, validation of a model and development of a simulator for predicting the pressure drop of clean and particulate-loaded DPFs are presented. The model, based on a previously developed theory, has been validated extensively in this work. The validation range includes utilizing a large matrix of wall-flow filters varying in their size, cell density and wall thickness, each positioned downstream of light or heavy duty Diesel engines; it also covers a wide range of engine operating conditions such as engine load, flow rate, flow temperature and filter soot loading conditions. The validated model was then incorporated into a DPF pressure drop simulator.

Various measurement techniques were employed to quantify sulfuric acid deposition levels and concentration of sulfuric acid in the condensate from the recirculated exhaust gas heat exchanger of a 1995 Cummins M11 heavy-duty diesel engine. Methods employed included a modified version of the sulfur species sampling system developed by Kreso et al. (1)*, rinsing the heat exchanger, and experiments employing a condensate collection device (CCD). The modified sampling system was applied to the inlet and outlet of the heat exchanger in order to quantify the changes in various sulfur compounds. Doped sulfur fuel (3300 to 4000 ppm S) was used to increase the concentrations of the various oxides of sulfur (SOx). These tests were performed at mode 9 of the old EPA 13-mode test cycle (1800 RPM, 932N*m) with 17-20% exhaust gas recirculation (EGR) at two EGR outlet temperatures: 160°C and 103°C.

A Computer-Aided Engineering (CAE) model for automobile climate control system is presented to provide engineers with an cost effective analysis tool for designing, developing, and optimizing the vehicle interior climate. It is the objective of this paper to develop a mathematical model which predicts the lumped temperature and lumped humidity variations inside the passenger compartment under design and operating conditions. The transient nature of the passenger cabin temperature, average interior mass temperature, and humidity are modeled using three coupled non-linear ordinary differential equations based on mass and energy balances. These equations are then solved by a fourth-order Runge-Kutta method with adaptive step size control.

The objective of this research was to evaluate the effects that higher fluid injection pressures and nozzle geometry have on compound fuel injector nozzle performance. Higher pressures are shown to significantly reduce droplet size, increase the discharge coefficient and reduce the overall size of a nozzle spray. It is also shown that the geometry has a significant effect on nozzle performance, and it can be manipulated to give a desired spray shape.

A major task of road and airfield maintenance for transportation departments in the Northern United States and in cold regions globally is snow removal. In addition, there is a service industry built on snowplow equipped light trucks to remove snow from vehicle serviceways and parking lots. Thus, a source of stresses on a truck frame are the forces applied by the plow. Unfortunately, very little research has been performed to provide design models that will predict these forces. In this paper, both theoretical and experimental work on developing expressions for snowplow forces will be discussed.

The current trend in the automotive industry is to minimize/eliminate cutting fluid use in most machining operations. Research is required prior to achieving dry or semi-dry machining. Issues such as heat generation and transfer, thermal deformation and fluid lubricity related effects on tool life and surface roughness determine the feasibility of dry machining. This paper discusses recent advances in achieving dry/semi-dry machining. As the first step, research has been conducted to investigate the actual role of fluids (if any) in various machining operations. A predictive heat generation model for orthogonal cutting of visco-plastic material was created. A control volume approach allowed development of a thermal model for convective heat transfer during machining. The heat transfer performance of an air jet in dry machining was explored. The influence of machining process variables and cutting fluid presence on chip morphology was investigated through designed experiments.

The goal of this research was to determine an empirical method of relating the droplet sizes and the spray patterns to the parameters and the geometries of the compound nozzles. Two different types of compound nozzles were studied, the compound silicon micro machined nozzle and the compound metal disk nozzle. Several different orifice geometries of each nozzle type were examined. The injector components upstream of the compound nozzle of two different types of injectors were also studied. A nondimensional characterization of the droplet sizes and the mass flow rates was proposed. The results of this study show that there exists optimum geometric features that will produce sprays with the minimum steady state and dynamic Sauter mean diameter. The spray of a compound nozzle can be characterized by the atomization efficiency and the discharge coefficient. Nozzle testing results show that many flow characteristics are developed in the compound nozzle.

The spray pattern of a fuel injector is a key factor in the mixing of the fuel with the air. One effective means of determining the fuel distribution in the spray is to collect the fuel in tubes, from various regions of the spray. The amount of fuel in the tubes is measured. These measurements are used to create diagrams and curves which graphically represent the fuel distribution within the spray. The term “Patternator” has come to mean a device which determines the spray distribution, in the sense that the device determines the pattern of the spray. The objective of this paper is to describe the operation, features, and performance of an automated patternator designed and built at Michigan Technological University for Ford Motor Company. The patternator system was constructed for rapid determination of the spray pattern in order to expedite the development of automotive port fuel injectors.

Too often many heat management problems are not solved with thermal analysis because of excessive complexity, time, and cost. A method for quickly solving a sophisticated thermal/fluid system with minimal user interaction and with common desktop computer resources is presented. A desktop (Microsoft Windows™) thermal analysis package, WinTherm, consists of the Generic Processor (pre-processing software), the 3-D Thermal Model (a finite difference nodal network solver), and an Image Viewer (wireframe and animated thermal display). The theoretical basis for this thermal analysis toolkit will be discussed as well as examples of its implementation.

The objective in this research is to investigate the effects of variable blank holder force (VBHF) on the material formability, due to its effect on the strain path. It is found in a recent study [9] that VBHF does not significantly affect the overall trend of the strain path. This strain path in deep drawing process is linear for the materials in the flange and under punch face, and is roughly bi-linear for the material around the punch nose. The second segment of the strain path in the punch nose region is plane-strain. VBHF, however, affects the strain ratio ρ1 = ε2/ε1 of the first segment of the bi-linear strain path. These effects, especially ρ1, on limit strain were studied using M-K method. A strain path dependent modified forming limit diagram (MFLD) was calculated based on the actual strain path. It is found that the MFLD is strongly dependent on ρ1.

A fast, semi-automated method for visualizing the time-varying effects of radiative heat transfer, including obscuration and multiple reflections, is presented. Starting with a finite element surface description, an analyst assigns “groups” to a model by indicating which elements have the same material and surface properties. The elements within each group are combined into isothermal nodes. View factors are then calculated using a variant of the hemi-cube method. Transient nodal temperatures are calculated using an implicit solution to the finite difference equations derived from the thermal properties of each node and the radiation exchange between nodes.

The formulation of mathematical model for the computational simulation of transient temperature response and phase change of refrigerant in a vapor condenser of an automotive air conditioning unit is described. A demonstrative computational simulation of a sample air cooled vapor condenser charged with Freon 12 is presented. The computational analysis predicts an initial surge and followed by an oscillation of the condensate outflow rate from the condenser when the air-conditioning unit is started, and the tube length required for complete condensation of inflow vapor is a maximum value at start up. The rise of the temperatures of the condenser tubes and cooling air flow during the start-up and load change operations rate found to be gradual but the scale of these temperature changes are considered small.

Steady state and dynamic spray characteristics of compound silicon micro machined port fuel injector orifices have been analyzed. Primary interest was placed on the Sauter mean diameter and the spray distribution. Orifice design parameters that influence droplet size and spray distribution were identified. The influence of injection pressure was investigated. The results of this investigation indicate that spray characteristics can be controlled by orifice geometry. Peak dynamic droplet sizes have been found to be significantly larger than steady state droplet sizes. Moderate increases in injector line pressure reduce spray droplet size without significantly affecting spray distribution.