Pressure-Free Surface-Induced Flow by Geometric Rectification

Zheng Li

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arXiv · 2512.18351

Pressure-Free Surface-Induced Flow by Geometric Rectification

Zheng Li

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Abstract

Pressure-driven flow collapses when confined ($u\propto r^{2}$). Asymmetry rectifies surface activity (exchange or slip gradients) into axial flux at $\Delta P=0$ despite zero net exchange. Lorentz reciprocity yields a projection law: throughput is the inner product of source with a geometry kernel. Signatures include inverted ``narrower-is-faster'' scaling ($u\propto r^{-1}$), leading-order viscosity independence, length amplification ($Q\propto L$), and linear superposition, defining surface-induced flow as a pressure-free Stokes-transport mode from microfluidics to physiology.

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Zheng Li. 2025-12-20. Pressure-Free Surface-Induced Flow by Geometric Rectification. https://arxiv.org/abs/2512.18351

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