海上风力发电机组塔架海波载荷的分析

由于海上风力发电机组的外界载荷条件比陆地上的风力发电机组更加复杂,因此在机组设计中要考虑到海上风机载荷条件.在研究海波性能和运动规律的基础上,给出了海水中的塔架载荷的计算公式;针对海上风力发电机组的结构特点,将研究的海波载荷计算方法用于风机的塔架载荷计算,以1.0 MW风力发电机组为例,对塔架所承受的海波载荷和风载荷进行了计算,经过对比分析可知,风载荷大于海波载荷并为同一数量级的载荷,因此,在设计中更应注意这两种载荷的耦合作用.

A joint method to retrieve directional ocean wave spectra from SAR and wave spectrometer data

This paper proposes a joint method to simultaneously retrieve wave spectra at dif ferent scales from spaceborne Synthetic Aperture Radar(SAR) and wave spectrometer data. The method combines the output from the two dif ferent sensors to overcome retrieval limitations that occur in some sea states. The wave spectrometer sensitivity coeffi cient is estimated using an ef fective signifi cant wave height(SWH), which is an average of SAR-derived and wave spectrometer-derived SWH. This averaging extends the area of the sea surface sampled by the nadir beam of the wave spectrometer to improve the accuracy of the estimated sensitivity coeffi cient in inhomogeneous sea states. Wave spectra are then retrieved from SAR data using wave spectrometer-derived spectra as fi rst guess spectra to complement the short waves lost in SAR data retrieval. In addition, the problem of 180° ambiguity in retrieved spectra is overcome using SAR imaginary cross spectra. Simulated data were used to validate the joint method. The simulations demonstrated that retrieved wave parameters, including SWH, peak wave length(PWL), and peak wave direction(PWD), agree well with reference parameters. Collocated data from ENVISAT advanced SAR(ASAR), the airborne wave spectrometer STORM, the PHAROS buoy, and the European Centre for Medium-Range Weather Forecasting(ECMWF) were then used to verify the proposed method. Wave parameters retrieved from STORM and two ASAR images were compared to buoy and ECMWF wave data. Most of the retrieved parameters were comparable to reference parameters. The results of this study show that the proposed joint retrieval method could be a valuable complement to traditional methods used to retrieve directional ocean wave spectra, particularly in inhomogeneous sea states.

An Integrated System-Oriented Model for the Interoperability of Multiple Emergency Response Agencies in Large-Scale Disasters: Implications for the Persian Gulf

Failures in complex technological systems could have multiple dire aftermaths, including many deaths and injuries. These events, such as nuclear accidents, pose serious threats and long-lasting health and environmental consequences to workers, the local public, and possibly the whole country and neighboring regions. Such failures,given interconnectivities and interdependencies, could also have spillover effects and threaten the integrity of other systems operating in the same area. There is an essential need for effective integration and interoperability among multiple emergency response agencies, possibly from different countries, in the case of an accident in a safetysensitive industry that causes the release of hazardous materials or contaminants. This article proposes a generic integrated system-oriented model to address this urgent need. It has been applied to the Persian Gulf area and its waters as a case study because of the existence of multiple co-located, safety-sensitive industries such as nuclear power generation, offshore oil and gas drilling, seawater desalination, and seafood harvesting. The Persian Gulf region and its ecosystems are highly vulnerable, and the countries around the Gulf are tightly interdependent, with an urgent need for cooperative emergency response planning. The Black Sea and other semiclosed, water-based ecosystems can also benefit from this model.