共查询到20条相似文献，搜索用时 31 毫秒
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可渗透结构具有使波浪作用减弱的效应,而海水的层化及水波的非线性使结构的波绕射产生多层复杂机制。将可渗透结构应用于复杂海况条件中,海水的层化性、波浪的非线性及结构的透空性构成了波绕射的一个十分复杂的数学问题。该问题存在理论研究的必要性,而文章则着重探讨其数学分析的可能性。通过引入二层海的层化海模式及Stokes二阶波的非线性波模式,给出了二阶多色波对透空结构的波绕射的定解问题提法,提出了复合形式的二阶多色波辐射条件式及可渗透结构的二阶物面条件式,应用特征函数解法与积分法推导了多色波对结构绕射的一阶势解与二阶作用的耦合积分解式,并讨论了解式所涉及无穷积分的算法。 相似文献
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该文提供分层海洋中运动物体生成内波的理论、数值和实验研究的背景资料的综述 ,并给出理论研究的 Green函数、正交模态模式和极点回避等方法的评述。数值研究给出数值求解Wronsky行列式的源求解方法及介绍直接差分计算含源内波方程和积分方程的方法。有关源致内波的实验研究 ,作者介绍物体在分层流水槽运动时生成内波的两个典型实验及其主要实验结果。最后评述船舶在海洋表面处生成表面波的研究方法 ,以此指导水下 Rankine卵形体生成内波的实验研究。 相似文献
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An information system for ocean wave resources and its application to wave power utilizationare indtroduced.It can manage,analyze and process the data in the monthly report of ocean wave observa-tion records of the State Ocean Administration,and can provide various kinds of curves and numericalcharacters of statistics.This system has been put into utility in Guangzhou Institute of Energy Conversion(GIEC),the Chinese Academy of Sciences since 1996.An application example is given of theinverstigation and analysis on ocean wave resource of the Nan Ao Island,Guangdong Province,where a100 kW onshore OWC(oscillating water column)wave power station will be built.The wave power distri-bution is obtained in different wave directions for different wave periods.It is found that 70 percent of thewave power comes from the direction of ENE,and more than 95 percent of the wave power is related withdirection E.The average wave power density is about 3 kW/m,and more than 80 percent of the wavepower is distributed in the 相似文献
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有界赤道大洋波包解及其年际年代际变率 总被引：1，自引：0，他引：1
Linearized shallow water perturbation equations with approximation in an equatorial β plane are used to obtain the analytical solution of wave packet anomalies in the upper bounded equatorial ocean. The main results are as follows. The wave packet is a superposition of eastward travelling Kelvin waves and westward travelling Rossby waves with the slowest speed, and satisfies the boundary conditions of eastern and western coasts, respectively.The decay coefficient of this solution to the north and south sides of the equator is inversely proportional only to the phase velocity of Kelvin waves in the upper water. The oscillation frequency of the wave packet, which is also the natural frequency of the ocean, is proportional to its mode number and the phase velocity of Kelvin waves and is inversely proportional to the length of the equatorial ocean in the east-west direction. The flow anomalies of the wave packet of Mode 1 most of the time appear as zonal flows with the same direction. They reach the maximum at the center of the equatorial ocean and decay rapidly away from the equator, manifested as equatorially trapped waves. The flow anomalies of the wave packet of Mode 2 appear as the zonal flows with the same direction most of the time in half of the ocean, and are always 0 at the center of the entire ocean which indicates stagnation, while decaying away from the equator with the same speed as that of Mode 1. The spatial structure and oscillation period of the wave packet solution of Mode 1 and Mode 2 are consistent with the changing periods of the surface spatial field and time coefficient of the first and second modes of complex empirical orthogonal function(EOF)analysis of flow anomalies in the actual equatorial ocean. This indicates that the solution does exist in the real ocean, and that El Ni?o-Southern Oscillation(ENSO) and Indian Ocean dipole(IOD) are both related to Mode 2.After considering the Indonesian throughflow, we can obtain the length of bounded equatorial ocean by taking the sum of that of the tropical Indian Ocean and the tropical Pacific Ocean, thus this wave packet can also explain the decadal variability(about 20 a) of the equatorial Pacific and Indian Oceans. 相似文献
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现场波浪观测技术发展和应用 总被引：1，自引：0，他引：1
介绍与海洋工程有关的应用于水下、水面、水上和太空不同空间位置的现场波浪观测技术。根据不同仪器量测的基本原理,分析其对工程应用的适合性和局限性;并讨论了现场波浪观测的发展趋势以及我国应采取的对策。 相似文献
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海浪的视景仿真有重要的应用背景与军事意义。文中围绕如何解决海浪的实时视景仿真问题,讨论了基于海浪谱的不同浪级波面的仿真模型,并讨论了海浪的实时视景仿真实现技术。这些模型与技术对于提高海浪仿真实时性与真实性有一定的参考价值。 相似文献
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福建沿海海域波浪能资源分析与评价 总被引：2，自引：0，他引：2
采用波浪模拟的方法,较准确计算得出福建沿海海域波浪能资源分布状况,并给出相应的分析和综合评价.主要结论如下:(1)福建沿海海域波浪能平均密度为2.6～7.3 kW/m,波浪能资源储量为2 210.45 MW,在我国沿海海域仅次于台湾和广东,是波浪能开发利用可以优先考虑的海区之一.(2)福建沿海海域波浪能资源储量的70%分布于平潭岛以北海域,其值达1 512.49 MW.其中,尤以北礵地区值最大,为378.80 MW.(3)以年平均波高为指标,福建沿海海域中东山区段为三类区,其他区段均为一类区和二类区,具有良好的开发前景.(4)福建沿海海域波浪能具有波功率密度低、资源分布广泛且不均匀、波功率密度随季节变化、能量具有多向性等分布特点.(5)基于福建波浪能的开发与利用现状,建议应优先着眼于解决边远海岛等特殊场所的用电问题. 相似文献
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In this paper, the radar cross section of flat plates on ocean surfaces is statistically investigated. A combining method of physical optics and geometric optics is applied to establish an effective backscattering analysis procedure. This method is a high-frequency analysis method originally derived from a simplified Stratton-Chu integral equation, assuming that the radar is far away from the target so that Kirchhoff approximation is valid. A Monte-Carlo simulation method is adopted to statistically analyze the effects of undulated ocean surfaces. The ocean surfaces are randomly generated by Pierson-Moskowitz ocean wave spectrum and a directional distribution function. Numerical investigations are carried out for flat plates, with the same height and width but with different inclined angles, on ocean surfaces of various significant wave heights. 相似文献
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海洋背景磁场模拟计算及东中国海表层磁场分布 总被引：1，自引：0，他引：1
海洋中海水的运动会切割地球磁场,生成微弱的电场,进而在海洋内部和周围空间激发感生电磁场,即约为地球磁场一万至十万分之一的微弱海洋背景磁场.文中针对海洋背景磁场的生成机制及近几十年来对海洋背景磁场的理论研究,结合世界磁场模型WMM2005,模拟计算了三种典型的海洋运动--海浪、海流、内波所产生的感应磁场,建立了海洋背景磁场的数值计算模型,并在此基础上设计开发了海洋背景磁场的模拟计算软件.最后用卫星多传感器资料驱动普林斯顿海洋动力学模式,得到的东中国海2005年海洋表层环流数据,模拟计算了东中国海海表层磁场分布,对其磁场变化与分布规律作了简要分析. 相似文献
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基于星载波谱仪海浪方向谱探测原理,仿真了不同海况、风速下的海浪波谱仪接收信号,并采用周期图法、Welch法、AR模型法以及最小方差法共4种不同的调制谱估计方法反演出海浪谱,比较各种调制谱估计方法的海浪方向谱反演性能。仿真结果表明:对于一定方位向下的一维海浪谱反演,不同调制谱估计方法反演海浪谱性能优劣没有绝对的顺序。对于二维海浪谱反演,在成长中海浪条件下周期图法反演性能最差,其他3种方法的反演性能没有绝对优劣顺序;对于成熟风浪,最小方差法在积分能量误差、有效波高误差两个指标上的反演性能最好,在主波波向、主波波长误差上,周期图法反演性能最差,其他3种方法没有绝对优劣顺序。在涌浪条件下,AR模型法反演性能优于其他3种方法。在不同海况下,随着波谱仪中心入射角的下降,反演性能会下降。基于这些仿真结果,本文推荐最小方差法作为充分成长海浪的海浪方向谱反演的调制谱估计方法,AR模型法作为涌浪海浪方向谱反演的调制谱估计方法。 相似文献
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全面地比较和总结了当前包括压力式测波、声学式测波、浮标式测波和遥测式测波在内的几种主要的海洋波浪测量方法的技术特点;对相应类型的典型代表型号的仪器主要技术指标进行了对比;对不同类型测量方法及其对应的仪器的具体适用环境给出了分析和建议。实际结合了ADCP,AWAC,Wave Duo测波浮球等几种海洋波浪测量仪器于2014年12月在江苏省南通市近海相近区域的同步实测数据,对这几种仪器的海洋波浪测量的响应和过程特征进行了对比和分析,这对相关的海洋波浪测量技术和对应的测波仪器设备特点也是一个很好的验证。 相似文献
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在大洋环流模型中对应于惯性内波破碎的垂直混合的一个参数化方案 总被引：1，自引：0，他引：1
Based on the theoretical spectral model of inertial internal wave breaking(fine structure) proposed previously, in which the effects of the horizontal Coriolis frequency component f-tilde on a potential isopycnal are taken into account, a parameterization scheme of vertical mixing in the stably stratified interior below the surface mixed layer in the ocean general circulation model(OGCM) is put forward preliminarily in this paper. Besides turbulence, the impact of sub-mesoscale oceanic processes(including inertial internal wave breaking product) on oceanic interior mixing is emphasized. We suggest that adding the inertial internal wave breaking mixing scheme(F-scheme for short) put forward in this paper to the turbulence mixing scheme of Canuto et al.( T-scheme for short) in the OGCM, except the region from 15°S to 15°N. The numerical results of F-scheme by using WOA09 data and an OGCM(LICOM, LASG/IAP climate system ocean model) over the global ocean are given. A notable improvement in the simulation of salinity and temperature over the global ocean is attained by using T-scheme adding F-scheme, especially in the mid- and high-latitude regions in the simulation of the intermediate water and deep water. We conjecture that the inertial internal wave breaking mixing and inertial forcing of wind might be one of important mechanisms maintaining the ventilation process. The modeling strength of the Atlantic meridional overturning circulation(AMOC) by using T-scheme adding F-scheme may be more reasonable than that by using T-scheme alone, though the physical processes need to be further studied, and the overflow parameterization needs to be incorporated. A shortcoming in F-scheme is that in this paper the error of simulated salinity and temperature by using T-scheme adding F-scheme is larger than that by using T-scheme alone in the subsurface layer. 相似文献
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为了验证波谱仪反演二维海浪谱的功能,根据海浪波谱仪的信号形成机制,总结了机载波谱仪反演海浪的流程。利用机载波谱仪回波数据,通过自相关和互相关两种功率谱估计方法,反演了二维海浪谱。最后通过与浮标测量的二维海浪谱进行对比,验证了该机载波谱仪探测二维海浪谱的有效性。结果表明,无论采用自相关函数还是互相关函数进行功率谱估计,得到的主波波长和有效波高与实际二维海浪谱基本一致。互相关函数法得到的交叉谱能去除180°模糊现象,其在计算有效波高时相对于自相关函数会稍微偏小。在计算斜率方差时可以采用5°~12°入射角范围的后向散射系数进行公式拟合,因此定标与否并不影响最后的二维海浪谱结果,未来星载波谱仪只有靠多波束联合才能实现。 相似文献
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This study makes use of the concept of wave age in estimating ocean wave period from space borne altimeter measurements of backscattering coefficient and significant wave height. Introduction of wave age allowed better accounting of the difference between swells and wind waves. Using two years (1998 and 1999) data of TOPEX/Poseidon altimeter and ocean data buoy observations in the Indian Ocean, coefficients were generated for wave period, which were subsequently tested against data for the years 2000 and 2001. The results showed the wave period accuracy to be of the order of 0.6 sec (against 1.3 sec obtained with the semiempirical approach, reported earlier). 相似文献
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This study makes use of the concept of wave age in estimating ocean wave period from space borne altimeter measurements of backscattering coefficient and significant wave height. Introduction of wave age allowed better accounting of the difference between swells and wind waves. Using two years (1998 and 1999) data of TOPEX/Poseidon altimeter and ocean data buoy observations in the Indian Ocean, coefficients were generated for wave period, which were subsequently tested against data for the years 2000 and 2001. The results showed the wave period accuracy to be of the order of 0.6 sec (against 1.3 sec obtained with the semiempirical approach, reported earlier). 相似文献