TY - JOUR

T1 - Experimental Observations of Meridional Flow Stagnation in a Three-Fluid Vortex

AU - Tintulova, M. V.

AU - Naumov, I. V.

AU - Sharifullin, B. R.

AU - Shtern, V. N.

N1 - The presented study was supported by the Russian Science Foundation, project no. 24-19-00233; https://rscf.ru/project/24-19-00233/

PY - 2025/4/18

Y1 - 2025/4/18

N2 - Abstract: In the search for a flow pattern optimal for culture growth in vortex bioreactors, our experiments discovered unusual flow structures that existing theoretical models cannot explain. Three immiscible liquids fill a vertical open cylindrical container of radius R = 47 mm whose sidewall is still while the bottom disk rotates driving a fluid motion. The centrifugal force pushes the lower liquid (L, aqueous glycerol) from the axis to the periphery near the bottom, creating its toroid circulation that in turn drives toroid circulations of the middle liquid (M, sunflower oil) and the upper liquid (U, alcoholic glycerine). With increasing rotation, counterflows develop near interfaces LM and MU: the liquids move towards (away from) the axis below (above) the interface that seems paradoxical. At a small thickness of M, a stagnation zone arises where the axial and radial velocities vanish and the M liquid only rotates. As M thickness decreases, this stagnation zone expands and occupies the entire volume of the middle liquid. These counterintuitive results await their theoretical explanation and formulation of new contact conditions at the LM and MU interfaces.

AB - Abstract: In the search for a flow pattern optimal for culture growth in vortex bioreactors, our experiments discovered unusual flow structures that existing theoretical models cannot explain. Three immiscible liquids fill a vertical open cylindrical container of radius R = 47 mm whose sidewall is still while the bottom disk rotates driving a fluid motion. The centrifugal force pushes the lower liquid (L, aqueous glycerol) from the axis to the periphery near the bottom, creating its toroid circulation that in turn drives toroid circulations of the middle liquid (M, sunflower oil) and the upper liquid (U, alcoholic glycerine). With increasing rotation, counterflows develop near interfaces LM and MU: the liquids move towards (away from) the axis below (above) the interface that seems paradoxical. At a small thickness of M, a stagnation zone arises where the axial and radial velocities vanish and the M liquid only rotates. As M thickness decreases, this stagnation zone expands and occupies the entire volume of the middle liquid. These counterintuitive results await their theoretical explanation and formulation of new contact conditions at the LM and MU interfaces.

UR - https://www.mendeley.com/catalogue/2562f4f4-660b-38b1-890a-cf59135d6518/

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-105003168266&origin=inward&txGid=8891df30a889ac0910856909c392a089

U2 - 10.1134/S1810232825010059

DO - 10.1134/S1810232825010059

M3 - Article

VL - 34

SP - 54

EP - 61

JO - Journal of Engineering Thermophysics

JF - Journal of Engineering Thermophysics

SN - 1810-2328

IS - 1

ER -