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arXiv · 2605.12254

Interfacial waves from pressure forcing: revisiting classical theories from an IVP perspective

Vinod Kumar Kadari·Nikhil Yewale·Palas Kumar Farsoiya·Y. S. Mayya·Ratul Dasgupta
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Abstract

A localised overpressure translating at a uniform speed greater than a critical value acts at the interface between two deep fluid layers with different densities. We analyse the resulting wave patterns using an initial-value problem formulation within the linearised, inviscid, potential flow framework. The steady-state interface exhibits short capillary waves ahead of the forcing and long gravity waves behind it, arising from an asymmetric cancellation of Fourier components in the far field. The time-dependent part of the solution, decaying algebraically with time, plays a crucial role in this mechanism. This contrasts with classical steady approaches, which require additional conditions to select a unique solution. We extend this approach to a two-fluid interface and validate the predictions against nonlinear simulations.

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Vinod Kumar Kadari, Nikhil Yewale, Palas Kumar Farsoiya, Y. S. Mayya, Ratul Dasgupta. 2026-05-12. Interfacial waves from pressure forcing: revisiting classical theories from an IVP perspective. https://arxiv.org/abs/2605.12254

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