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To ensure safety regarding dust explosion hazards, it is important to study the dust lifting process experimentally and identify important parameters that will be valuable for development and validation of numerical predictions of this phenomenon. A new shock tube test section was developed and integrated into an existing shock tube facility. The test section allows for shadowgraph or laser scattering techniques to track dust layer particle motion. The test section is designed to handle an initial pressure of 1 atm with an incident shock wave velocity up to Mach 2 to mimic real world conditions. The test section features an easily removable dust pan and inserts to allow for adjustment of dust layer thickness. The design allows for the changing of experimental variables including initial pressure, Mach number, dust layer thickness and characteristics of the dust itself. A separate vacuum manifold was designed to protect existing equipment from negative side effects of the dust. A study was performed to demonstrate the capabilities of the new facility and to compare results with experimental trends formerly established in the literature. Forty-micron limestone dust with a layer thickness of 3.2 mm was subjected to Mach 1.22 and 1.38 shock waves, and a high-speed shadowgraph was used for flow visualization. Dust layer rise height was graphed with respect to shock wave propagation. Dust particles subjected to a Mach 1.38 shock wave rose more rapidly and to a greater height with respect to shock wave propagation than particles subjected to a Mach 1.22 shock wave. These results are in agreement with trends found in the literature, and a new area of investigation was identified.

The use of chemiluminescence measurements to monitor a range of combustion processes has been a popular area of study due to their reliable and cost-effective nature. Electronically excited carbon dioxide (CO2*) is known for its broadband emission, and its detection can lead to valuable information; however, due to its broadband characteristics, CO2* is difficult to isolate experimentally, and the chemical kinetics of this species is not well known. Although numerous works have monitored CO2* chemiluminescence, a full kinetic scheme for the species has yet to be developed. A series of shock-tube experiments was performed in H2-N2O-CO mixtures highly diluted in argon at conditions where emission from CO2* could be isolated and monitored. These results were used to evaluate the kinetics of CO2*, in particular, the main CO2* formation reaction, CO + O + M CO2* + M (R1). Based on collision theory, the quenching chemistry of CO2* was determined for eleven common collision partners. The final mechanism developed for CO2* consisted of 14 reactions and 13 species. The rate for R1 was determined based on low-pressure experiments performed in two different H2-N2O-CO-Ar mixtures. Final mechanism predictions were compared with the experimental results at low and high pressures, with good agreement seen at both conditions. Peak CO2* trends with temperature as well as overall CO2* species time histories were both monitored. Comparisons were also made with previous experiments in methane-oxygen mixtures, where there was slight over-prediction of CO2* experimental trends by the mechanism.Experimental results and mechanism predictions were also compared with past literature rates for CO2*, with good agreement for peak CO2* trends, and slight discrepancies in overall CO2* species time histories. Overall, the ability of the CO2* mechanism developed in this work to reproduce a range of experimental trends represents an improvement over existing models.

No description available.

No description available.

No description available.

No description available.

No description available.