Investigation of Non-Newtonian pseudo plastic fluid behavior ingas-liquid agitated tank

A non-Newtonian pseudo plastic fluid is investigated in two phase gas-liquid system in agitated vessel equippedwith ASI (Axial-Radial) impeller, by using a noninvasive flow visualization technique, electrical resistancetomography. The main goal of this study is to investigate the effect of gas dispersion on the behavior of non-Newtonianfluid. In this work, xanthan gum solution in different concentration is used as yield-pseudo plastic fluid and air is usedfor gas phase which dispersed to liquid from the bottom of vessel by a sparger. The experiments are carried out ingassed condition with different gas flow rate, and the effect of impeller speed, xanthan gum concentration and gasflow rate on mixing time, and power consumption is explored and the results compared with the performance ofRushton turbine and pitch blade impeller. The analysis of experimental results shows that ASI impeller is moreeffective than the two other impellers from the point of mixing time, unlike the power consumption in two phasesnon-Newtonian agitated system. We found a linear relationship between power consumption and Re for our non-Newtonian gas- liquid agitation system by using ASI impeller as𝑝𝑣= 𝑐 . 𝑅𝑒. 𝐹𝑟 which C is a logarithmic function ofconcentration as 𝐶 = ۵ × ۱۰۱۰ 𝑒−۰.۰۲𝜌 where ρ is the density of solution.

Keywords:

Xanthan Gum , Pseudo Plastic Fluid , Mixing Time , non-Newtonian Fluid , ASI Impeller.