dc.contributor.author | Li, Yan | |
dc.contributor.author | Ellingsen, Simen Andreas Ådnøy | |
dc.date.accessioned | 2019-02-15T10:20:24Z | |
dc.date.available | 2019-02-15T10:20:24Z | |
dc.date.created | 2018-11-22T09:53:28Z | |
dc.date.issued | 2018 | |
dc.identifier.isbn | 978-0-7918-5127-2 | |
dc.identifier.uri | http://hdl.handle.net/11250/2585675 | |
dc.description.abstract | We analyze surface waves generated by a translating, oscillating surface disturbance atop a horizontal background flow of arbitrary depth dependence, with a focus on determining the Doppler resonance. For a critical value of the dimensionless frequency τ = ωV/g (ω: oscillation frequency, V: source velocity, g: gravitational acceleration) at which generated waves cannot escape. In the absence of shear the resonant value is famously 1/4; the presence of a shear current modifies this. We derive the theoretical and numerical tools for studying this problem, and present the first calculation of the Doppler resonance for a source atop a real, measured shear current to our knowledge. Studying graphical solutions to the (numerically obtained) dispersion relation allows derivation of criteria determining the number of far-field waves that exist in different sectors of propagation directions, from which the criteria for Doppler resonance follow. As example flows we study a typical wind-driven current, and a current measured in the Columbia River estuary. We show that modeling these currents as uniform or with a linear depth dependence based on surface measures may lead to large discrepancies, in particular for long and moderate wavelengths. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | ASME | nb_NO |
dc.relation.ispartof | ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 7B: Ocean Engineering | |
dc.title | Surface Waves Generated by a Translating and Oscillating Source Atop Realistic Shear Flows | nb_NO |
dc.title.alternative | Surface Waves Generated by a Translating and Oscillating Source Atop Realistic Shear Flows | nb_NO |
dc.type | Chapter | nb_NO |
dc.description.version | publishedVersion | nb_NO |
dc.source.pagenumber | V07BT06A056-? | nb_NO |
dc.identifier.doi | 10.1115/OMAE2018-78560 | |
dc.identifier.cristin | 1633605 | |
dc.description.localcode | Copyright © 2018 by ASME | nb_NO |
cristin.unitcode | 194,64,25,0 | |
cristin.unitname | Institutt for energi- og prosessteknikk | |
cristin.ispublished | true | |
cristin.fulltext | postprint | |
cristin.qualitycode | 1 | |