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951.
本文简述了自动监测系统现场安装的重要性,提出了设备安装的检查,现场的准备,及设备的安装方法和注意事项。 相似文献
952.
Analyses are presented of field measurements of spectral transfer functions between surface elevation and subsurface three-dimensional particle velocity in wind-generated waves, in conditions ranging from young seas to old swells. The results are in agreement with the linear theory predictions to within the measurement error margin, which is estimated to be ± 5% for the gain functions and ± 4° in phase as far as the possible systemic errors are concerned. No correlation is found of the degree of agreement between measurements and linear theory with wave age or wave sleepness. 相似文献
953.
954.
基于MCT耦合器,利用中尺度大气模型WRF、海洋模型FVCOM和第三代海浪模型SWAN,实现大气、海洋和海浪的三者实时耦合计算,同时采用卫星微波辐射资料AMSU-A,通过WRF大气模式的资料同化模块WRFDA,实现对风场模拟的连续同化,从而建立起大气-海洋-海浪耦合与卫星数据同化的W-F-S-A耦合同化模式。将该模型应用于2014年台风“威马逊”的数值模拟,并与其他模型进行比较。结果表明,W-F-S-A耦合同化模式对于台风路径和风速的模拟结果优于单独耦合和单独同化结果,并且可以较好地模拟上层海洋对台风的响应特征。 相似文献
955.
956.
郭佩芳 《中国海洋大学学报(自然科学版)》1993,(2)
本文以风浪频谱和其相关函数的关系为基础,应用积分中值定理,给出了风浪相关函数的理论模型。进而以文氏等人的理论风浪频谱为原型,通过数值积分和待定系数法,给出了以风浪频谱的零阶矩m_0、峰频率ω_0和峰度因子P为参数的深水风浪相关函数式。最后把该式与数值计算值、实测值作了对比,证明本文所提出的深水风浪相关函数式较好地反映了各种不同成长状态的实际的相关函数。 相似文献
957.
Typhoon is regarded as a convergent,modified Rankine vortex.Based on the vorticity equations written attwo levels,higher and lower in the troposphere,typhoon motions are discussed in this study.The analyticalexpressions of vortex motion direction and speed have been derived for simple homogeneous basic flows at twolevels.The expressions indicate that in the easterties,vertical wind shear enhances the steering of east flow,causing the vortex moving westward faster,otherwise,in the westerlies,it reduces the steering of the west flow,causing the vortex moving eastward slower.These results explain theoretically that“cyclones in the easterliesmove to the right of,and faster than the basic flow;conversely,cyclones in the westerlies move to the left of,andslower than the basic flow.” 相似文献
958.
The daily and monthly-mean characteristics of cold water patches(CWPs) off the Jiangsu coast in 35 a of1982–2016 are examined based on advanced very high resolution radiometer(AVHRR) data. Most of the CWPs are found to occur in the warm and hot months(May–September), with some CWPs in the cool and cold months(October–April). The average radius and intensity of the monthly-mean CWPs are about 81 km and 0.6°C,respectively. The average difference in the sea surface temperature(SST) between the centers of the CWPs and the nearshore is about 2.0°C. The correlation analysis between the CWPs, winds and tides indicates that most of the CWPs occurred during the southerly winds, with some CWPs occurring during the northerly winds. The average intensity of the CWPs during spring tides is slightly stronger than that during neap tides in the warm and hot months, and the difference is very small in the cool and cold months. 相似文献
959.
960.
The eigenfrequency of offshore wind turbine structures is a crucial design parameter, since it determines the dynamic behavior of the structure and with that the fatigue loads for the structural design. For offshore wind turbines founded on monopiles, the rotational stiffness of the monopile-soil system for un- and reloading states strongly affects the eigenfrequency. A numerical model for the calculation of the monopile’s behavior under un- and reloading is established and validated by back-calculation of model and field tests. With this model, a parametric study is conducted in which pile geometry, soil parameters and load conditions are varied. It is shown that of course the rotational stiffness varies with mean load and magnitude of the considered un- and reloading span, but that for most relevant load situations the initial rotational stiffness of the monopile system, i.e. the initial slope of the moment-rotation curve for monotonic loading, gives a good estimate of the actual stiffness. Comparisons of different p–y approaches show that the ordinary API approach considerably underestimates the initial stiffness, whereas the recently developed ‘Thieken’ approach and also the ‘Kallehave’ approach give a much better prediction and thus might be used in the design of monopiles in sand. 相似文献