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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.

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 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.

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.

An optical technique for measuring transient combustion chamber surface temperatures in a fired engine has been developed. The spectral region from 3.6 to 4.0 microns was found to be suitable for making optical measurements through the methane-air flame. The experimental apparatus was capable of making simultaneous time-resolved measurements of infrared gas absorption, gas emission and surface radiation during a single engine cycle. The effects of engine operating conditions on gas absorption and gas emission were investigated. Measurements of “simulated” deposits at temperatures ranging from 569 K to 944 K indicated that the technique was accurate within 7 K at the higher temperatures.

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.

The First Annual Blizzard Baja was hosted by Michigan Technological University's SAE Student Branch on February 7, 1981. This was a competition between student designed vehicles which had previously competed in summer Baja events. The Blizzard Baja consisted of a one hour endurance race run on ice and snow. The purpose was to provide the student engineers an opportunity to test their vehicles in cold weather, snow and icy conditions.