Title Stochastic asymmetry properties of 3D Gauss-Lagrange ocean waves with directional spreading
Authors Georg Lindgren, Finn Lindgren
Alternative Location http://dx.doi.org/10.1080/1..., Restricted Access
Publication Stochastic Models
Year 2011
Volume 27
Issue 3
Pages 490 - 520
Document type Article
Status Published
Quality controlled Yes
Language eng
Publisher Taylor & Francis
Abstract English In the stochastic Lagrange model for ocean waves the vertical and horizontal location of<br> surface water particles are modeled as correlated Gaussian processes. In this article we investigate<br> the statistical properties of wave characteristics related to wave asymmetry in the 3D Lagrange<br> model. We present a modification of the original Lagrange model that can produce front-back<br> asymmetry both of the space waves, i.e. observation of the sea surface at a fixed time, and<br> of the time waves, observed at a fixed measuring station. The results, which are based on a<br> multivariate form of Rice’s formula for the expected number of level crossings, are given in<br> the form of the cumulative distribution functions for the slopes observed either by asynchronous<br> sampling in space, or at synchronous sampling at upcrossings and down-crossings, respectively,<br> of a specified fixed level. The theory is illustrated in a numerical section, showing how the<br> degree of wave asymmetry depends on the directional spectral spreading and on the mean wave<br> direction. It is seen that the asymmetry is more accentuated for high waves, a fact that may be<br> of importance in safety analysis of capsizing risk.
Keywords Crossing theory, Directional spreading, Front-back asymmetry, Gaussian process, Palm distribution, Rice formula, Slope asymmetry, Wave steepness.,
ISBN/ISSN/Other ISSN: 1532-4214 (online)

Questions: webmaster
Last update: 2013-04-11

Centre for Mathematical Sciences, Box 118, SE-22100, Lund. Telefon: +46 46-222 00 00 (vx)