A blend time investigation for stirred tanks was conducted to study the effect of impeller type (A310 Hydrofoil, Pitched-Blade Turbine, Rushton Turbine), impeller diameter (D/T = 1/5, 1/3, and 1/2), and impeller off-bottom distance (C/T = 1/5, 1/3, and 1/2) while considering tank diameter (T = 0.80 and 1.22 m) and mean specific energy dissipation (ε = 0.005 and 0.010 W/kg) for turbulent Newtonian fluids with square batch aspect ratios. The response of conductivity probes to the injection of a sodium chloride tracer was monitored to experimentally measure blend time for 108 unique setups. The results of the blend time experiments were recorded, analyzed to determine trends, compared to a well-established correlation, and fit to generate modified correlations. A modified turbulent blend time correlation capable of predicting statistically similar blend time for 99% of experimental setups is proposed as a function of tank diameter, impeller diameter, impeller off-bottom distance, textbook values of impeller power number, and impeller rotational frequency.
Mechanical Engineering (MS)
Department, Program, or Center
Mechanical Engineering (KGCOE)
Strand, Aaron, "Investigation of Blend Time for Turbulent Newtonian Fluids in Stirred Tanks" (2017). Thesis. Rochester Institute of Technology. Accessed from
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