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This work contributes to the understanding of physical mechanisms that control flashback, or more appropriately combustion recession, in diesel sprays. A large dataset, comprising many fuels, injection pressures, ambient temperatures, ambient oxygen concentrations, ambient densities, and nozzle diameters is used to explore experimental trends for the behavior of combustion recession. Then, a reduced-order model, capable of modeling non-reacting and reacting conditions, is used to help interpret the experimental trends. Finally, the reduced-order model is used to predict how a controlled ramp-down rate-of-injection can enhance the likelihood of combustion recession for conditions that would not normally exhibit combustion recession. In general, fuel, ambient conditions, and the end-of-injection transient determine the success or failure of combustion recession.

This paper outlines the design of a part transport and loading/unloading automation system for a cylindrical die thread roller, enumerating many of the design decisions encountered. Specifically, a transport tray system is proposed and prototyped as a benchmark for factory automation. Details of an automation system which will interface with the proposed transport tray system are discussed. A gripping system which accommodates a wide variety of fastener head styles is developed to work in conjunction with the tray concept, and prototyped with favorable results.

Compressive load capacity of composite lattice structures are studied. The objective of this research is to investigate the buckling strength of composite lattice structures and to design the most weight efficient structure with the highest buckling load. Buckling strength of both the composite lattice cylindrical and conical shells under axial compressive loads are examined. The main emphasis is placed on the effects of geometric constraints and the optimal design of the structures. In this research, various constraints are studied and the optimal structure which gives the highest strength to weight ratio is obtained. Moreover, these structures can be constructed by filament winding, the manufacturing process can be automated, and the costs can be greatly reduced.

This paper outlines a comprehensive, structured, and robust methodology for decision making in the early phases ofaircraft design. The proposed approach is referred to as the Technology Identification, Evaluation, and Selection (TIES) method. The seven-step process provides the decision maker/designer with an ability to easily assess and trade-off the impact of various technologies in the absence of sophisticated, time-consuming mathematical formulations. The method also provides a framework where technically feasible alternatives can be identified with accuracy and speed. This goal is achieved through the use of various probabilistic methods, such as Response Surface Methodology and Monte Carlo Simulations. Furthermore, structured and systematic techniques are utilized to identify possible concepts and evaluation criteria by which comparisons could be made.

In this paper, we quantify several environmental benefits associated with using ultra fine scrap tire rubber powders in virgin and recycled rubber and plastics compounds. Specifically, we will analyze the savings in oil extraction and rubber production in comparison to the rubber powder production using cryogenic grinding. The analysis uses first hand factory data provided by a rubber powder producer. As will be shown, even though cryogenic nitrogen requires production and use of liquid nitrogen, there is still a net environmental benefit in terms of energy use and greenhouse gas emissions.

The characteristics of cordierite type compositions and the relationship between thermal expansion and raw materials, processing, and gross composition are examined. Other possible support materials are reviewed briefly. These include mullite, zircon, beryl, spodumene, aluminum titanate, silicon nitride, and other low expansion compositions. Raw material cost, processing, and reactivity with the catalysis are discussed for these materials.