Date of Graduation
Bachelor of Science in Chemical Engineering
Throughout the US, large quantities of chlorine are produced and transported by rail. In the past, train accidents led to deadly accidental releases and the need for mass evacuation. However, moving people unnecessarily may cause pandemonium or danger to health for sensitive members of the public. In these past cases, the models used for evacuation distances did not accurately predict the impact of the chlorine release, but these models did not take into account the reactivity of chlorine. Because chlorine is a highly reactive gas, it is absorbed into the surrounding environment which reduced the amount of chlorine in the air thereby reducing the impact of an accidental release. In this context, the Controlled Environment Reactivity Test (CERT) program was created to determine the extent of the absorption of chlorine with the environment. The Chemical Hazard Research Center (CHRC) at the University of Arkansas is active member of the program. Its facility is used to conduct low wind speed dispersion modeling for various hazardous gases. For the CERT Program, the aim is to create a test chamber designed to provide chemical reactivity (deposition) data for direct use in atmospheric dispersion models.
This particular project aimed at designing and constructing a test chamber to provide gas mixtures in preparation for the CERT Tests. Preliminary tests were conducted to validate the set-up. The chamber is made of plywood and clear polycarbonate, powered by a small 2 hp fan used to push the air through the chamber to the room. Based on previous work, High Efficiency Vortex (HEV) mixer design has been adapted to mix test gas with inlet air. The HEV mixer is placed directly after the fan and uses two sets of inline baffles to produce turbulent mixing. The testing included the delivery of the gas (fog) to the chamber, the determination of the optimal setup for all experiments, and the preliminary videos. An optimal height for the inlet nozzle of five inches was determined and the similarity between the fog speed and the air speed on the lowest fog and fan setting has been proven. Finally, the preliminary videos of the chamber flow clearly show a large scale vortical structure which is convected along the length of the test section. This undesirable structure is caused by the fan. A flow straightener could be used to reduce or eliminate this phenomenon.
Holmes-Smith, Holly, "Design, construction, and preliminary testing of a square cross-sectional mixing chamber" (2016). Chemical Engineering Undergraduate Honors Theses. 96.