Stability of an accelerated hydrodynamic discontinuity
Abstract
We analyze from a far field the evolution of an accelerated interface separating ideal incompressible fluids of different densities. We develop and apply a general matrix method and identify a new fluid instability that occurs only when the acceleration magnitude exceeds a threshold value depending on the fluids' density ratio and uniform velocities and the perturbation wavelength. The dynamics conserves the fluxes of mass, momentum and energy, has potential velocity fields in the bulk, and is shear-free at the interface. The interface stability is set by the interplay of inertia and acceleration. Surface tension may also stabilize the dynamics by a distinct mechanism. The growth rate, the flow fields' structure and stabilization mechanisms of this new fluid instability depart substantially from those of other instabilities, thus suggesting new opportunities for the understanding, diagnostics, and control of interfacial dynamics.
Additional Information
© 2019 EPLA. Received 28 July 2018; Accepted 7 December 2018; Published 21 January 2019.Additional details
- Eprint ID
- 92473
- Resolver ID
- CaltechAUTHORS:20190125-113146718
- Created
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2019-01-25Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field
- Other Numbering System Name
- WAG
- Other Numbering System Identifier
- 1320