Hannover 2010 – wissenschaftliches Programm
UP 2.5: Poster
Dienstag, 9. März 2010, 16:30–18:30, Lichthof
Wavemeasurements with different principles (ast and bouy) — •Jörg Bendfeld, Martin Tigges, and Michael Splett — Universität Paderborn / WUZ, Paderborn, Deutschland
In most cases a wave is described mathematically by a wave equation in only two dimensions (namely deflection and propagation direction of the wave). If it is the intention to consider the wave motion holistically and thus to describe the real sea behaviour, it is necessary to superimpose a plurality of individual waves having different frequency and amplitude values, so an exact mathematical description becomes very complicated and almost impossible on account of the large number of imponderables. The superimposition is not trivial. It involves non-linear components (particularly in the case of wind-induced waves), which are predictable only with great difficulty or not at all. It is simpler to assess the wave events according to the probability of their occurrence. In this case measurements of the wave height are of primary interest. Thereby the distance between ground and surface (ast, acoustic surface tracking) or the accelerated motion of the water surface (buoy) is utilised as measured signal. Thus the two measuring methods differ fundamentally in their physical functional principle. Therefore all parameters that are relevant with respect to the measuring instrument must be evaluated separately. Subsequent comparisons and any differences in the respective measuring sequences can thus be interpreted.