Record Details
Bispectral and cross-bispectral analysis of wind and currents off the Oregon coast
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Bispectral and cross-bispectral analysis of wind and currents off the Oregon coast |
| Names |
Yao, Neng-chun G., 1934-
(creator) Neshyba, Steve (advisor) |
| Date Issued | 1974-02-26 (iso8601) |
| Note | Graduation date: 1974 |
| Abstract | Third order spectra computed from the rotary components of winds and currents at the TOTEM buoy site off the Oregon coast provide an insight to the nonlinear, quadratic interactions within and between these vector fields. The topography of bispectra and cross-bispectra as displayed on four tri-frequency planes shows that significant nonlinear interaction takes place between triples of oscillatory components over wide ranges of frequencies. A quantitative evaluation of the energy transferred linearly and non-linearly from wind to current is obtained through the development of a set of general, complex-valued transfer functions for two-dimensional vector random processes. Using a postulated "cause-effect" relation between measured surface wind stress and current at 14 m (within the mixed layer), the inertial frequency energy in the current field is attributed solely to the non-linear transfer of momentum from the wind field. The transfer occurs from multiple pairs of frequencies (in the intermediate frequency range) in the wind field, with the dominant transform attributed to the wind stress oscillations at half-day and quarter-day periods. In the intermediate frequency range, 63% of the total kinetic energy in the 14 m current is derived from the wind stress through nonlinear processes, but only about 7% of the total kinetic energy in the current at 34 m, below the mixed layer, is related indirectly to this source. |
| Genre | Thesis/Dissertation |
| Topic | Winds -- Oregon |
| Identifier | http://hdl.handle.net/1957/23451 |
