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Electroosmotic lubrication in constricted microchannels with a compliant wall and DLVO disjoining pressure

Subhajyoti Sahoo and Ameeya Kumar Nayak*

  • *Contact author: ameeya.nayak@ma.iitr.ac.in
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Phys. Rev. Fluids 11, 064201 – Published 2 June, 2026

DOI: https://doi.org/10.1103/2fhz-5l14

Abstract

We develop a nonlinear model for electroosmotic transport through a constricted microchannel with a rigid curved upper wall and a compliant lower wall. The framework couples Helmholtz-Smoluchowski slip under a globally constrained electric field, lubrication hydrodynamics, quasistatic Kirchhoff-Love wall bending, and Derjaguin-Landau-Verwey-Overbeek disjoining pressure. The response is governed by wall stiffness, geometric curvature, surface conduction, and the strengths of the repulsive and attractive intermolecular interactions. Asymptotic analysis and fully coupled Chebyshev-collocation computations reveal three regimes: a stiff-wall regime with negligible deformation, a compliance-limited regime in which localized throat narrowing suppresses throughput, and a small-gap saturation regime in which further thinning becomes progressively slower because of the coupled elastic, hydrodynamic, and disjoining-pressure response. In the strong-constriction limit, geometric focusing amplifies the electric field and produces a sublinear increase of throughput with curvature, whereas in the localized-throat limit the deformation and compliance-induced flux reduction are organized by the effective stiffness BC2. The results provide compact, design-oriented scaling laws for compliant electroosmotic constrictions and clarify how stiffness, curvature, surface conduction, and minimum-gap interactions regulate transport in soft microfluidic, biosensing, drug-delivery, and iontronic systems.

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Corrections

14 August, 2026

Correction: Author names in Ref. [30] were displayed incorrectly and have been fixed.

Article Text

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Information

Phys. Rev. Fluids 11, 064201– Published 2 June, 2026
  • Received 23 November 2025
  • Accepted 30 April 2026
  • Corrected 14 August 2026
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