Date of Award
Master of Science (MS)
Current industrial abrasive blasting nozzles are often loud enough to negatively impact worker health and require employers to implement hearing conservation programs under OSHA noise exposure regulations. Significant opportunity exists for the use of modern computational fluid dynamics software (CFD) in the design of an abrasive blasting nozzle with a focus on reducing the acoustic intensity. Past work using CFD for abrasive blasting nozzle design has focused on improving productivity, ignoring aeroacoustic considerations. ANSYS Fluent software was used to investigate the effect of geometry changes to a commercially available No. 6 venturi nozzle, specifically the addition of a constant cross-section cylindrical nozzle extension at the end of the diverging portion of the nozzle. Two categories of steady-state, multi-phase simulations were run, those in which the blast media did not exchange energy with the air flowing through the nozzle (discrete phase interaction disabled), and those in which the blast media did exchange energy with the air flowing through the nozzle (discrete phase interaction enabled). The simulations were then compared to hand calculations of the fluid and media velocities to establish simulation accuracy, followed by collection of acoustic data from physical nozzles which were then compared directly to the simulation results to establish the accuracy of the trends predicted by the simulations. The simulations which accounted for the exchange of energy between the blast media and the air flowing through the nozzle were found to provide similar trends to the experimental results while the simulations which did not account for the exchange of energy between the blast media and the air flowing through the nozzle were found to provide similar trends to the theoretical calculations.