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1.
We investigate the influence of baroclinic tidal waves on the diffusion of an impurity spot in a continuously stratified liquid. The equation of turbulent diffusion is solved numerically by taking into account the wave currents. We establish the dependences of the characteristics of the diffusion process on the parameters of the baroclinic wave and the location of the impurity spot. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

2.
We study the influence of baroclinic tidal waves on the diffusion of an impurity spot in a continuously stratified fluid. The equation of turbulent diffusion is solved numerically by taking into account the wave currents. We establish the dependences of the characteristics of the diffusion process on parameters of baroclinic waves and the location of the impurity spot. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

3.
For a one type of temperature turbulent convection observed in the ocean, i.e., for the two-dimensional roller-type convection, we propose a model intended for the evaluation of the intensity and depth of penetration of convective motions as functions of a given heat flow from the sea surface and the temperature gradient in the thermocline. This model is based on the methods of the theory of turbulent jets and experimental data on the vertical distribution of temperature in the course of convection. The comparison of the calculated dimensionless values of the depth of penetration of the thermocline in autumn and winter shows a good qualitative agreement with the data ofin situ measurements. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

4.
With the help of a combined model of wind and waves, we study the influence of films of surfactants on the spectrum of short wind waves and the parameters of the lowest layer of the atmosphere. It is shown that the films of surfactants decrease the roughness of the sea surface as a result of suppression of short wind waves, which decreases the coefficient of resistance of the sea surface and the coefficient of turbulent heat exchange. The maximum influence of films on the exchange coefficients is attained forU∼10 m/s. In this case, the relative decrements of the coefficients of resistance and turbulent heat exchange are equal to 15 and 9%, respectively. Translated by Peter V. Malyshev and Dmitry V. Malyshev UDC 551.46  相似文献   

5.
We discuss the results of numerical experiments modelling the process of propagation of passive impurities from the Karantinnaya Bay caused by steady wind currents and turbulent diffusion. The currents are computed according to the Felzenbaum model for the cases of northeast and north-west winds [1, 2]. We analyse specific features of the space and time distribution of the impurities caused by the three-dimensional character of the currents. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

6.
A method of statistical separation of fine-structure fluctuations according to their origin is applied to the analysis of the characteristics of mixing in a layer located below the summer temperature minimum in the Black Sea. The simplification of the procedure of numerical evaluation of the coefficient of vertical wave exchange enabled us to perform the comprehensive fine-structure processing of the data of regular surveys of the Black Sea with an aim to determine the spatial distribution of the field intensity of small-scale internal waves and the intensity of mixing caused by these waves in the analyzed layer. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

7.
We study the problem of flow around an ellipsoidal body submerged in a liquid half space and obtain the solution for the free wave surface. The results of numerical analysis reveal the existence of a great variety of modes of motion characterized by substantially different shapes of the free surface. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

8.
For various stratifications and different types of bottom patterns we study the transformations of solitary perturbations of density appearing in the depth of the sea. In the two-dimensional case, under the assumption that the average dynamic characteristics weakly vary in time as compared with the wave characteristics, we deduce the equations for mean currents and waves taking into account vertical and horizontal viscosity and the diffusion of density. Numerical examples show that the stratification, bottom topography, nonlinearity, mean currents, and dissipation strongly affect both the process of splitting of a solitary wave into wave trains and their amplitude and length. The wave currents exhibit the oscillatory (train-like) character. It is emphasized that, in the case of propagation of solitary perturbations of density with dissipation, it is also important to take into account the combined influence of nonlinearity, currents, bottom topography, and stratification. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

9.
We present an analytic survey of a series of works devoted to the direct methods for the investigation of turbulence in natural basins originated under the guidance of A. G. Kolesnikov in the 50s. We describe the principal results of the early stage which formed the basis for future investigations. The main scientific directions of the latest period are also considered from the viewpoint of the development of Kolesnikov's ideas: investigation of the processes of generation and energy supply of small-scale turbulence, relationship between turbulence and the fine vertical structure and internal waves, and the mechanisms of vertical turbulent exchange in the ocean. A model of vertical exchange under the conditions of intermittent “source” turbulence is distinguished. We also discuss the directions of development and prospects of the investigation of turbulence. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

10.
We analyze the results of investigation of turbulent boundary layers typical of geophysical objects. It is shown that boundary layers of various nature are self-regulating sustems characterized by relatively slow evolutionary processes of formation accompanied by the growth of instabilities of different types and then replaced by the rapid development of instabilities and destruction of the boundary layers. This cycle is repeated with a certain quasiregular frequency. The destruction of the boundary layer is accompanied by the ejection of turbulent structures whose parameters are characterized by stable experimentally reproducible mean values. This mechanism is responsible for the process of exchange in the boundary layers. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

11.
《Ocean Modelling》2011,39(3-4):267-279
Near-surface enhancement of turbulent mixing and vertical mixing coefficient for temperature owing to the effect of surface wave breaking is investigated using a two-dimensional (2-D) ocean circulation model with a tidal boundary condition in an idealized shelf sea. On the basis of the 2-D simulation, the effect of surface wave breaking on surface boundary layer deepening in the Yellow Sea in summer is studied utilizing a 3-D ocean circulation model. A well-mixed temperature surface layer in the Yellow Sea can be successfully reconstructed when the effect of surface wave breaking is considered. The diagnostic analysis of the turbulent kinetic energy equation shows that turbulent mixing is enhanced greatly in the Yellow Sea in summer by surface wave breaking. In addition, the diagnostic analysis of momentum budget and temperature budget also show that surface wave breaking has an evident contribution to the turbulent mixing in the surface boundary layer. We therefore conclude that surface wave breaking is an important factor in determining the depth of the surface boundary layer of temperature in the Yellow Sea in summer.  相似文献   

12.
We consider the problem of geostrophic adjustment of nonlinear axially symmetric formations in a two-layer fluid with infinitely deep lower layer and demonstrate the existence of a new integral of motion, which enables us to determine the final equilibrium state of perturbations without analyzing the transient (wave) stage of the process. It is shown that the final motions caused by initial perturbations of the opposite signs are not equivalent. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

13.
We describe a differential approach to the spectral composition of thin thermohaline inhomogeneities in the ocean depending on the mechanisms responsible for their generation and demonstrate the possibilities of this approach in getting realistic hydrophysical results. The statistical classification of fine-structure fluctuations according to their origin is performed on the basis of the joint analysis of the temperature, salinity, and density spectra computed in a section of the vertical profile where the variation of mean gradients of all three parameters is insignificant. On the basis of the constructed mean spectrum of wave elevations, we estimate the dissipative characteristics of the convection of salt fingers and small-scale internal waves. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
Free waves (seiches) in a circular basin of variable depth are studied numerically within the framework of the linear theory of long waves taking into account the action of the Coriolis force. We determine the frequencies of axisymmetric and circular waves, study the structure of the modes of elevation of the free surface and wave velocities, and establish the dependences of the phase velocities of circular waves on the number of mode and wavelength. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
A nearshore wave breaking model   总被引:4,自引:0,他引:4  
AnearshorewavebreakingmodelLiShaowu,WangShangyi,TomoyaShibayama(ReceiuedOctober8,1996;acceptedFebruary26,1997)Abstract-Awaveb...  相似文献   

16.
一种近岸区波浪破碎模型   总被引:7,自引:0,他引:7  
从波浪破碎的能量关系入手,以紊流能量方程为基础,考虑破碎区内单个波在不同破碎阶段所提供的紊动能量强度的变化过程,提出了一种波浪破碎模式.通过将这一模型引入Boussinesq方程中,初步建立了一种近岸区波浪变形数学模型,并用波浪水槽实验资料对模型模拟波高和平均水位的情况进行了初步验证,得到了良好的结果.  相似文献   

17.
Within the framework of the linear theory of long waves, we perform the numerical investigation of transformations of a barotropic diurnal tide in the process of its motion from the deepwater region of the sea into the region of continental slope and shelf zone at any angle to the coast line. For a linear profile of the bottom of the continental slope and shelf, we establish dependences of the amplitudes and velocities of waves on the direction of propagation of the tidal wave and the latitude of the place. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
Internal waves generated by a barotropic wave impinging on a bottom ridge with continuously varying height are studied within the framework of the linear theory of long waves. We consider the case where the diurnal tide travels at an arbitrary angle to the axis of the ridge located in the area of a geostrophic flow caused by tilting of the free sea surface and the interface of a two-layer ocean. We study the dependences of the amplitudes of internal waves on the velocity of the geostrophic flow, the direction of propagation of the barotropic tide, and the geometry of the ridge. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

19.
We describe the hydrological structure of waters of the Persian Gulf and its seasonal variability according to the data of CTD surveys carried out in February–June 1992 in the course of the cruises of the NOAA R/VMt. Mitchell aimed at the analysis of the consequences of the ecological catastrophe caused by the spread of oil spots formed as a result of war operations in the Persian Gulf in 1991. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

20.
波浪破碎过程产生的湍流动量和能量垂向输运对于加快海洋上混合层中垂向混合具有显著效果.采用二维实验室水槽中对波浪破碎过程进行模拟.对采集的波浪振幅时间序列采用希尔伯特变换定位破碎波位置,波浪的破碎率随有效波高的增加而增大,波浪谱分析得到的波浪基本周期与有效周期结果相似.实验中采用粒子图像测速技术(particle ima...  相似文献   

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