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This study presents the design, construction and testing of an Outdoor Gas Emission Sampling (OGES) System capable of gas sampling and calorimetry in outdoor conditions with wind. In large-scale, outdoor fire tests, wind-driven emission plumes present a challenge in heat release rate quantification because the emission plume rises upward at an angle. A new gas sampling system with a flexible hood design and smaller control volume has been designed and tested. Bulk flow rate, oxygen, carbon dioxide, and carbon monoxide concentrations are measured for heat release rate calculations. Two stages of experimentation are described. Experiments at intermediate-scale (indoor only) that were conducted to evaluate the performance of a smaller control volume for measurements, and large-scale (indoor and outdoor) experiments, to demonstrate feasibility in realistic field conditions as well as the new flexible hood design. Experiments show that the OGES system is capable of calculating the heat release rate of pool fires with an accuracy of 23% using oxygen consumption (OC) and carbon dioxide generation (CDG) methods. Further improvements of the OGES system for outdoor field deployment are also discussed.

Energy release rates are extracted from non-linear finite element analyses of a thin film bonded to a rigid substrate that is shaft-loaded at its free edge. This geometry is of interest because it simulates a probe test that has proven to be useful in characterizing the adhesion of thin, microelectronic coatings bonded to silicon wafers. Preliminary experimental results indicate that out-of-plane rather than in-plane loading dominates failure in the system. This work therefore focuses on out-of-plane film loading. To validate finite element and energy release rate methodologies, energy release rates from finite element analyses of pressurized and shaft-loaded blister tests are first correlated to theoretical limit cases. Upon validation, mode I, mode II, and mode III energy release rates are extracted from three-dimensional continuum finite element models of the edge-loaded thin film by a three-dimensional modified crack closure method. Having assumed a circular debond as observed experimentally, energy release rates are determined by a step-wise approach around the circumference. The progression of debond is simulated in multiple analyses by altering the boundary conditions associated with increasing the debond radius. Mechanical loading is supplemented with thermal loading, introducing residual stresses in the non-linear analyses. A sensitivity analysis of energy release rates to residual stress is performed. The results indicate that inclusion of residual stress has an important role in both the magnitude and mode-mixity of energy release rates in the thin film. Increasing the length of debond effectively transitions the film from a shearing mode to a bending mode, thereby significantly impacting each mode of energy release rate differently. / Master of Science

Six poly(ether ketone ketone)/carbon composite panels were manufactured from powder coated towpreg. All six panels were initially processed using a hot press equipped with controlled cooling. Four of the panels were used to investigate the effect of cooling rate on crystallinity. A fifth panel was used to investigate the effect of annealing the composite after completion of the standard fabrication process. The sixth panel was used to investigate changes in toughness due to manufacturing towpreg with polymer that had been reclaimed from the towpreg fabrication system’s air cleaner. Cooling rates of 2°C/min, 4°C/min, 6°C/min, and 8°C/min resulted in composites with crystallinities of 33%, 27%, 24%, and 23%, respectively. The principal investigation of the effect of cooling rate on crystallinity and mode I and mode II strain energy release rates, G_Ic and G_IIc, respectively, showed that G_Ic and G_IIc values increase with increasing cooling rate. Comparison of the toughness values as a function of crystallinity showed that the dependence of toughness on crystallinity is approximately equivalent to the dependence of toughness on cooling rate. Comparison of the data from the annealed panel to that from the analogous principal panel showed that annealing increased the crystallinity and decreased the mode I strain energy release rate. There was no effect, however, on the mode II strain energy release rate. Comparison of the data from the panel made with reclaimed polymer to that from its analogous principal panel showed that the reclaimed polymer panel had equivalent crystallinity and G_Ic values. On the other hand, the G_IIc values in this panel were lower than in the analogous principal panel. / Master of Science