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1.
最大熵原理应用于海浪波高分布的研究   总被引:5,自引:0,他引:5  
利用最大熵原理从理论上推导出波高的最大熵分布,在此基础上研究了状态参量对波高分布和波高熵的影响。影响最大熵分布的因子是平均波高和状态参量,不同海况对应的状态参量是不同的。利用波高实测资料,得出3种不同海况下的最大熵分布,通过比较发现最大熵分布很好地符合实测数据。把最大熵分布与目前广泛应用的瑞利分布作了比较,结果表明,最大熵分布有2个优点:没有对波高作出任何限制性假定和能够描述不同海况下的波高分布。  相似文献   

2.
使用1992年IO月到1998年12月连续共75个月、230个重复周期的Topex/Poseidon卫星高度计有效波高资料,对南、北太平洋波高熵的空间分布特征和时间变化规律进行了研究。统计分析了太平洋波高熵的多年的空间分布特征和多年各月的时间变化规律。结果表明,太平洋波高熵呈现出中间低、南北高的马鞍形空间分布特征和明显季节变化的规律,与太平洋的平均有效波高和气候分布特征和变化规律相一致。给出了南北太平洋模拟波高熵的计算公式及计算稳定性检验。  相似文献   

3.
为研究近岸浪的形态特征,利用LPB1-2型声学测波仪在某海域所测得的海浪数据对近岸浪特征要素进行统计分析,利用最大"熵"原理推导出了波高的最大"熵"分布,研究了状态参量对波高分布和波高"熵"的影响。研究表明,该海域的波主要以波高0.3~0.7 m,周期2.5~5.5 s的波为主,表示离散程度的特征值平均差为0.267,日极差值主要在0.1~0.4 m区间内,最大值为1.0 m,分布较为集中,波高分布近似为正态分布。  相似文献   

4.
使用1992年10月-1998年12月连续75个月、230个重复周期的Topex/Poseidon卫星高度计有效波高资料,对南北大西洋波高熵的空间分布特征和时间变化规律进行了研究,统计分析了大西洋波高熵的多年的空间分布特征和多年各月的时间变化规律。结果表明,大西洋波高熵呈现出中间低、南北高的马鞍形空间分布特征和明显季节变化的规律,与大西洋的平均有效波高、气候的地理分布以及大气活动分布特征和变化规律相一致。  相似文献   

5.
设计波高推算的一种新模型   总被引:1,自引:0,他引:1  
考虑台风影响海域的设计波高,结合复合极值理论和最大熵原则,构造了1种新型的具有4个待定参量和1个台风频次参量的poisson-最大熵分布函数模型,并推导出求解参数的方程组,参数的数值解可通过年极值实测数据的期望、方差、偏度和峰度得到.以黄海某观测站26 a极值波高的实测数据为例计算了新模型中4个待定参量和多年一遇设计波高,并与传统常用计算方法得到的结果进行比较.比较表明,新模型相比传统方法具有一定的优势.  相似文献   

6.
The new distributions of the statistics of wave groups based on the maximum entropy principle are presented.The maximum entropy distributions appear to be superior to conventional distributions when applied to a limited amount of information.Its applications to the wave group properties show the effectiveness of the maximum entropy distribution.FFT filtering method is employed to obtain the wave envelope fast and efficiently.Comparisons of both the maximum entropy distribution and the distribution of Longuet-Higgins(1984) with the laboratory wind-wave data show that the former gives a better fit  相似文献   

7.
本文将小波分析用于波群结构和波群中波破碎的研究。实验结果表明,波群中波动的振幅不是关于波群中央对称的,而是波群前部波动的振幅较大。这种不对称性导致波群前部单个波的波陡较大,后部单个波的波陡较小,当谱宽度增大时波群前部与后部单个波的平均波陡之差增大。波群前部波陡较大导致波群前部的波动最容易发生破碎,而不是波群中央的波动最容易发生破碎,波群中波动最可能发生破碎的位置距波群中央的长度为波群长度的1/6。  相似文献   

8.
The experimental studies of the wave breaking effects on freak wave generation are presented within a finite-depth random wave train in a laboratory wave tank. The main attention is paid to the abnormal index,AI=Hmax/Hs,being used to characterize the freak waves,and the changes of the coefficient due to wave breaking. The results show that the occurrence probability of freak wave events in non-breaking waves is much larger than that in breaking waves and such occurrence in deep water is larger than that in ...  相似文献   

9.
-The effect of wave group on wave run-up on a slope dike is mainly discussed in this paper. Two simulating methods of wave group and their applications in laboratory are introduced. Synthesizing the research results of wave run-up on a slope dike, the effect of wave group on wave run-up on a slope dike in coastal protection engineering is studied as the main point.  相似文献   

10.
The experimental studies of the wave breaking effects on freak wave generation are presented within a finite-depth random wave train in a laboratory wave tank. The main attention is paid to the abnormal index, AI=Hmax/Hs, being used to characterize the freak waves, and the changes of the coefficient due to wave breaking. The results show that the occurence in deep water is larger than that in shallow water.  相似文献   

11.
在实验室风浪槽中观测风浪,发现波群连长是影响波群中波高分布的重要因素,随着波群连长增大,波群中波高分布信息熵增大。当以平均波高无因次化,连长较大时波群中波高累积概率明显大于连长较小时情形。波群中波高分布受谱宽度影响。当谱宽度增大,波群中波高累积概率降低。谱宽度和波群连长对波群中波高累积概率的影响相当。引进体现波群特性的1个无因次化波高参量研究波群中波高累积概率。  相似文献   

12.
Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth''s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irrotational. The third-order Stokes wave solutions are given by using a perturbation method. The results indicate that the third-order solutions depend on the surface tension, the density and the depth of each layer. As expected, the first-order solutions are the linear theoretical results (the small amplitude wave theoretical results). The second-order and the third-order solutions describe the nonlinear modification and the nonlinear interactions. The nonlinear impact appears not only in the n (n≥2) times'' high frequency components, but also in the low frequency components. It is also noted that the wave velocity depends on the wave number, depth, wave amplitude and surface tension.  相似文献   

13.
通过分析实验室风浪资料,研究风浪波高间的相关性以及波群中波高累积概率问题,发现风浪波高间相关性虽然主要发生在相邻波之间,但在隔1个波和隔2个波的波高间仍存在一定的相关性。谱宽度对波高间的相关性产生影响,但在相邻波、隔1个波和隔2个波情形下,谱宽度对波高间的相关性的影响方式不同。在相邻波情形下,谱宽度主要影响较大波高间的相关性,对各种高度波高间的总体相关性影响很小。而在隔1个波和隔2个波情形下,谱宽度对各种高度波高间的总体相关性有明显影响。根据实验结果提出含有波高相关因子的波群中多个波波高累积概率分布。  相似文献   

14.
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   

15.
在三维随机海浪数值模拟的基础上,获得了波峰的空间分布。为了验证由不同的波峰定义方法得到的波峰长度和波峰方向角等特征量的准确性,对直接利用波峰边界上距离最远的两点之间距离定义波峰长度和利用椭圆拟合波峰和以椭圆的要素定义波峰长度2种不同方法得到的波峰长度统计结果进行了比较,发现由2种方法定义得到的波峰特征量的值基本一致,尤其是波峰长度个数的统计值极为接近,由2种方法得到的统计值精确度相当。这表明,不同定义方法对边界不规则波峰长度统计值的影响较小。  相似文献   

16.
鉴于传统熵与时间无关 ,不能反映海 -气耦合机制下海浪场的基本属性———不可逆性 ,文章将非平衡信息论熵的概念引入海浪场的研究。依据海浪场相空间的Fokker Planck方程 ,首次推导出了非平衡信息论熵的熵平衡方程、熵密度、熵流密度、熵产生密度、广义力和广义力密度的具体表达式。  相似文献   

17.
根据线性系统理论,首先由给定的靶谱模拟海浪信号,再把此信号转换为造波控制输入信号,最后在水槽中指定的截面处产生具有给定靶谱的随机波。这种模拟方法已在青岛海洋大学物理海洋实验室的大型水槽中实现,并取得良好的效果。  相似文献   

18.
介绍了实验室的造波机系统和造波特性及其在模型试验中的应用,并讨论了实验室内模拟海浪的检验标准及其方法。并对造波机应用前景进行讨论,对不规则波造波机进行物模试验具有一定的现实意义。  相似文献   

19.
LI  Yanbao 《中国海洋工程》2002,16(2):211-218
In this paper, the theoretical analysis and experimental studies are employed to investigate the reflection characteris-tics of partial standing waves caused by wave overtopping and sloping top of structures. Based on the principle of conser-vation of wave energy flux, the third-order Stokes wave theory is used to formulate the reflection coefficient at wave overtopping; the calculation results are regressed into an applied expression. A series of experiments of wave reflection for a vertical-wall structure with chamfered and overhanging upper sections are carried out to investigate the influence of top slope on wave reflection. The regularity of variation of wave reflection in this case is analysed based on the experimental results.  相似文献   

20.
In this paper, the extreme wave loads on an on-shore wave power device are investigated. First, boundary element method is applied to solve the three dimensional potential problem based on the small amplitude wave assumption. Then the motion of the Oscillating Water Column (OWC) inside the device and its laods on the device are calculated in time domain. Several protective techniques often applied are simulated by changing the constraint of the upper end of the chamber of the device. Numerical results are used to judge the effectiveness of these techniques. The investigation shows that damping can not effectively restrain the motion of OWC when the period of incident wave is long, which may cause dangerous loads on the structure. The shut chamber can effectively restrain the motion of OWC, but alternatively cause high pressure in the chamber. A Contracting opening with a Taper (CT) can exhaust a great amount of kinetic energy of OWC, and significantly decrease the loads. It is a promising protective tec  相似文献   

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