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.

Library of Congress Subject Headings

Newtonian fluids--Mathematical models; Mixing--Fluid dynamics--Mathematical models

Publication Date


Document Type


Student Type


Degree Name

Mechanical Engineering (MS)

Department, Program, or Center

Mechanical Engineering (KGCOE)


Edward Hensel

Advisor/Committee Member

Risa Robinson

Advisor/Committee Member

Steven Day


RIT – Main Campus

Plan Codes