title: Electrokinetically modulated peristaltic transport of power-law fluids.
abstract: The electrokinetically modulated peristaltic transport of power-law fluids through a narrow confinement in the form of a deformable tube is investigated. The fluid is considered to be divided into two regions - a non-Newtonian core region (described by the power-law behavior) which is surrounded by a thin wall-adhering layer of Newtonian fluid. This division mimics the occurrence of a wall-adjacent cell-free skimming layer in blood samples typically handled in microfluidic transport. The pumping characteristics and the trapping of the fluid bolus are studied by considering the effect of fluid viscosities, power-law index and electroosmosis. It is found that the zero-flow pressure rise is strongly dependent on the relative viscosity ratio of the near-wall depleted fluid and the core fluid as well as on the power-law index. The effect of electroosmosis on the pressure rise is strongly manifested at lower occlusion values, thereby indicating its importance in transport modulation for weakly peristaltic flow. It is also established that the phenomenon of trapping may be controlled on-the-fly by tuning the magnitude of the electric field: the trapping vanishes as the magnitude of the electric field is increased. Similarly, the phenomenon of reflux is shown to disappear due to the action of the applied electric field. These findings may be applied for the modulation of pumping in bio-physical environments by means of external electric fields.
authors.affiliation: Department of Mathematics, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
authors.forename: Prakash
authors.initials: P
authors.lastname: Goswami
authors.affiliation: Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
authors.forename: Jeevanjyoti
authors.initials: J
authors.lastname: Chakraborty
authors.affiliation: Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
authors.forename: Aditya
authors.initials: A
authors.lastname: Bandopadhyay
authors.affiliation: Advanced Technology Development Centre, Indian Institute of Technology Kharagpur, Kharagpur 721302, India; Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302, India. Electronic address: suman@mech.iitkgp.ernet.in.
authors.forename: Suman
authors.initials: S
authors.lastname: Chakraborty
mesh_terms: D004560:Electricity; D053841:Electroosmosis; D004867:Equipment Design; D007700:Kinetics; D008962:Models, Theoretical; D009038:Motion; D011312:Pressure; D019736:Prostheses and Implants; D011673:Pulsatile Flow; D014783:Viscosity
keywords: Electroosmosis; Peristaltic flow; Power-law fluid; Reflux; Trapping