Spectral Methods for capillary surfaces described by bounded generating curves

Ray Treinen

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arXiv · 2205.02931

Spectral Methods for capillary surfaces described by bounded generating curves

Ray Treinen

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Abstract

We consider capillary surfaces that are constructed by bounded generating curves. This class of surfaces includes radially symmetric and lower dimensional fluid-fluid interfaces. We use the arc-length representation of the differential equations for these surfaces to allow for vertical points and inflection points along the generating curve. These considerations admit capillary tubes, sessile drops, and fluids in annular tubes as well as other examples. We present a pseudo-spectral method for approximating solutions to the associated boundary value problems based on interpolation by Chebyshev polynomials. This method is observably more stable than the traditional shooting method and it is computationally lean and fast. The algorithm is also adaptive, but does not use the adaptive automation in Chebfun.

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Ray Treinen. 2022-05-05. Spectral Methods for capillary surfaces described by bounded generating curves. https://arxiv.org/abs/2205.02931

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