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Wave energy assessments in the Black Sea 总被引:1,自引:0,他引:1
Eugen Rusu 《Journal of Marine Science and Technology》2009,14(3):359-372
The present work aims to evaluate the wave energy resources in the Black Sea basin. The study is focused on the western part
of the sea, which is traditionally considered as being more energetic. In order to give a first perspective of the wave climate,
a medium-term wave analysis was carried out using in situ measured data. As a further step, a wave prediction system was implemented
for the Black Sea. This was based on the simulating waves near-shore model, which is used for both wave generation and near-shore
transformation. This methodology has the advantage that a single model covers the full scale of the modelling process. Various
tests were performed considering data measured at three different locations. Special attention was paid to the whitecapping
process, which is still widely considered to be the weak link in deep water wave modelling. Comparisons carried out against
measured data show that the wave prediction system generally provides reliable results, especially in terms of significant
wave heights and mean periods. By increasing the resolution in geographical space, the field distributions of wave energy
were analysed for both high and average wave conditions. The analysis and the wave prediction system developed are a prerequisite
for further investigations extended in time and with increased resolution in the near-shore direction. 相似文献
2.
Eugen Rusu 《Journal of Marine Science and Technology》2010,15(2):143-159
The target of the present study is the entrance to the Danube Delta in the Black Sea. The wave conditions in this coastal
sector are usually significant from an energetic point of view and the relatively strong currents induced there by the outflow
from the Danube lead to interactions between waves and currents. This process modifies considerably both the magnitude and
direction waves, affecting also coastal navigation and sediment transport patterns. In order to assess the effects of the
wave–current interactions, the simulating waves nearshore (SWAN) model was considered for developing a multilevel wave prediction
system. Validations against measured data were carried out for each computational level. Five case studies corresponding to
the most relevant patterns of the environmental matrix were analyzed. Finally, in order to assess the current effect for a
longer timescale, an analysis concerning the variation of the main wave parameters was performed for a 3-month period considering
some reference points. The results show that the currents produce considerable changes in the wave field, especially as regards
the significant wave heights, mean wave directions and wavelengths. The Benjamin–Feir index was also estimated. The analysis of the variation induced by the current over this spectral shape parameter indicates
that, in certain conditions, in the target area the wave heights cannot be considered Rayleigh distributed and freak waves
may also occur. 相似文献
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A system for forecasting the operability of ships was developed by extending a wave forecasting system with the ship responses to the forecast sea states. The system produces 4-day wave forecasts in an implementation for the Portuguese Exclusive Economic Zone, where the vessels’ seakeeping performance is forecast, although the method presented could well be applied to any other coastal region. The proposed procedure requires the knowledge of the transfer functions for different ship speeds and headings. The computations are made for two different types of fishing vessels that currently operate in the Portuguese coast. Ship motions and derived responses are evaluated with a strip theory code and compared with the prescribed values of relevant seakeeping criteria that represent the limit conditions that still allow standard operational conditions for those vessels. For each forecast sea state at each grid point at a given time, the response spectrum is calculated and operability indexes are computed and compared with the maximum allowed values for a specific operation criterion. The results are presented as operational index maps for various areas of the Portuguese coast, and the information provided by system will help ship masters to plan the operation of their ships, namely to decide the areas to operate in anticipation. In this way, they can identify areas in which the level of operationally of their ships will be degraded due to weather conditions and avoid them. 相似文献
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