Forward and Inverse Problems in Towed Cable Hydrodynamics

Polydorides, Nick and Storteig, Eskild and Lionheart, William (2008) Forward and Inverse Problems in Towed Cable Hydrodynamics. [MIMS Preprint]

PDF linear_oe.pdf Download (555kB)

Abstract

This paper addresses the problem of reconstructing the velocities of t he ocean currents impinging on a towed streamer cable during an offshore seismic survey. This study considers a two-dimensional model describing the motion of a flexible, inextensible cable in the presence of hydrodynamic drag forces in an in compressible fluid. In the first part the forward model is introduced and then sol ved to yield the cable’s velocity, curvature and tension in the knowledge of the towing vessel motion and the hydrodynamic loads applied. In sequence, we formul ate the inverse problem of inferring the ocean current velocities from discrete samples of the cable’s shape and tension and show that this is rank deficient and ill-posed. In approaching the inverse problem a numerically stable algorithm is adopted based on generalized Tikhonov regularization, in the context of robust differentiation of discrete noisy signals. In order to demonstrate the practical performance of the scheme, some examples of ocean current reconstructions obtain ed using simulated noisy data are presented.

Item Type:	MIMS Preprint
Uncontrolled Keywords:	towed seismic array, ocean current, inverse problem
Subjects:	MSC 2010, the AMS's Mathematics Subject Classification > 34 Ordinary differential equations MSC 2010, the AMS's Mathematics Subject Classification > 76 Fluid mechanics PACS 2010, the AIP's Physics and Astronomy Classification Scheme > 80 INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY > 89 Other areas of applied and interdisciplinary physics
Depositing User:	Prof WRB Lionheart
Date Deposited:	15 Jul 2008
Last Modified:	08 Nov 2017 18:18
URI:	https://eprints.maths.manchester.ac.uk/id/eprint/1128

Actions (login required)

View Item