Doctor of Philosophy, The Ohio State University, 2024, Food, Agricultural and Biological Engineering

The smoking process for a food product involves the deposition and absorption of smoke on the product surface, followed by a drying step to reduce the product moisture content to a defined level. The uniformity of air velocity and temperature within a smokehouse significantly influences final product quality, including color, texture, and flavor. Additionally, process efficiency and production capacity depend on uniform heat and mass transfer at the surface for all products in the smokehouse. While Computational Fluid Dynamics (CFD) has been used to study airflow patterns, air velocity and temperature distributions due to ventilation systems, research on applications to airflow distribution in a smokehouse have been limited. The overall objective of this research was to develop and validate CFD simulations of a smokehouse ventilation system to investigate the applications to airflow uniformity within a smokehouse. A CFD simulation of airflow distribution in a smokehouse without product was developed and used to investigate the influence of smokehouse ventilation configuration on uniformity of air velocity. The ventilation system configuration with outlet vents positioned near the inlet vents at both sides of the smokehouse ceiling exhibited the highest air velocity uniformity index of 0.64. An investigation of three different outlet vent dimensions indicated that outlet vent size did not influence the uniformity of air velocity distribution within the empty smokehouse. The influence of model products in the smokehouse was investigated using the CFD simulation. The average air velocity at 20 locations decreased from 3.9 ±1.4 m/s to 2.7 ±0.90 m/s when the ratio of model product to smokehouse volume was increase from 0 to 0.047. The influence of ventilation configuration was also evaluated by comparing outlet vents positioned near the inlet vents at both sides of the smokehouse ceiling to the outlet vent located in the ceiling at the middle of the smokehouse. The ave (open full item for complete abstract)

Committee: Dennis Heldman (Advisor); Sudhir Sastry (Committee Member); Sandip Mazumder (Committee Member); Osvaldo Campanella (Committee Member) Subjects: Engineering; Fluid Dynamics; Food Science

MS, Kent State University, 2023, College of Arts and Sciences / Department of Earth Sciences

Piping or internal erosion has been responsible for almost half of all dam failures worldwide. In this research, we studied the influence of grain size heterogeneity, as characterized by sediment size (d50) and the uniformity coefficient (Cu), on piping potential. A novel experimental setup was designed in-house that included sediment mass, pressure, and turbidity sensors allowing the examination of transient changes during piping events. Porosity and conductivity were analyzed in order to compare trends across varying grain size distributions. Mass values of soil lost during piping failure via a continuous mass balance and a turbidity meter to capture fines that remain in suspension were both utilized to capture the magnitude of piping failure. Minute Piping and Clogging events that are only able to be captured via the pressure transducers were recorded during this experiment, adding complexity to the onset of piping phenomena. The smaller the Cu, the less clogging events occurred before piping failure. It was noted that these minute piping and clogging events would stabilize as the sediment column reached equilibrium. This research allows for further studies to expand on these piping and clogging events as well as depicted trends between soil heterogeneity and piping potential.

Committee: Kuldeep Singh (Advisor); David Hacker (Committee Member); Anne Jefferson (Committee Member) Subjects: Civil Engineering; Earth; Engineering; Environmental Engineering; Environmental Geology; Experiments; Geology; Hydrologic Sciences; Hydrology; Soil Sciences