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Turbulence Department
Anatoly S. Samodurov- Head of Turbulence Department
Scientists - 10; Engineers - 6; Technician - 3
Department of turbulence is one of the eldest scientific
departments existing from the day of foundation of the Marine
Hydrophisical Institute. The leaders of department since 1963 year
were professor A.G. Kolesnikov, professor N.A. Panteleev.
Basic scientific directions
 Theoretical and
experimental investigations of the processes of mixing due to the
influence of various physical mechanisms (turbulence, shear
instability and break dawn of internal waves, double diffusion,
near-bottom friction etc.), with the purpose of detecting their
contribution to the vertical and horizontal turbulent exchange in
marine systems;
Research of the
processes of vertical and horizontal turbulent exchange of heat,
salt, different chemical and biological matters in abyssal and shelf
zones of the Black Sea with the purpose of monitoring and forecast
of evolution of its physical and biochemical state under varying
natural and anthropogenic effects;
Development of new
methods of study and principles of construction of instruments for
investigating small-scale processes in marine systems;
Carrying out of in
situ measurements of the processes under study.
Project
National programs
«Research of regularities of functioning of shelf ecosystems in the
conditions of anthropogenic and technogenic loads» (Project
"Shelf").
«Interdisciplinary researches of fundamental processes of forming
and evolution of an ecosystem of the Black sea deep-water part in
the conditions of intensive anthropogenic load, regional variations
and global changes of climate» (Project "Ecosystem")
National program of protection and rehabilitation of the environment
of the Black and Azov seas;)
«Present state of the shelf area and recommendation on use of the
shelf mineral resources»).
International programs
EC INCO Copernicus Project (1997-2000, IC15CT96-113) Ventilation of
the Black Sea Anoxic Layer;
NATO SfP Linkage Grant (1999-2002, EST.CLG 975821) The Role of
Transport Processes on the Ventilation and Biogeochemical Cycling in
the Black Sea ;
United States Civilian Research and Development Foundation For the
Independent States of the Former Soviet Union (2000-2001, CRDF#UG2-2238)
Nitrogen cycling in the oxic/anoxic environment of the Black Sea :
Modeling based on data analysis;
EC project INTAS (2000-2002, INTAS#99-01710) Nitrogen cycling in the
oxic/anoxic environment of the Black Sea : data analysis and
numerical simulation;
United States Civilian Research and Development Foundation For the
Independent States of the Former Soviet Union (2002-2003, CRDF#UG1-2432-SE-02)
Modeling alterations in biogeochemical cycles of the Black Sea oxic/anoxic
ecosystem in response to climate change;
EC project INTAS (2002-2004, INTAS#01-2280) Methane Budget for the
oxic/anoxic water column of the Black Sea : data synthesis,
parameterization of biochemical transformations, numerical
simulation;
Black Sea European Research Program (GEF/BSERP, 2004);
Project « Black Sea - 2004».
Results
Main developments of the department
Complex “Vostok-M” intended to measure flow speed, temperature and
conductivity on the depths up to 200 m .
Multifunctional measuring device “Sigma- 1” developed in the
department of turbulence is intended to measure hydrophysical
parameters of the ocean fields: 3-D velocity, temperature and
conductivity fluctuations and average values of temperature,
conductivity and pressure. The device has two modifications: the
position mode with the cable transfer of information to a computer
and the probing mode with a data record on the internal registration
block at free submergence up to the depth of 100 meters . The device
is equipped with the system of position control: azimuth
transmitter, roll and trim difference sensors.
more information
Main results of works
• The model of climatic spectrum of internal waves in the ocean is
constructed; its adjusting requires no choosing of free parameters
(information on the structure of the observed spectra);
• The method of determining dependencies of the vertical diffusion
coefficient and the rate of energy dissipation upon the local
stratification is developed and applied in practice. The method
based on the statistic analysis of the array of temperature vertical
spectra measured under various stratification conditions.
• The model of vertical exchange due to the tidal friction on the
slope bottom in a stratified basin is constructed; it includes
dependence of the vertical diffusion coefficient upon the external
conditions.
• The model of vertical exchange due to the geothermal heat flux on
the slope bottom in a stratified basin is constructed; it includes
dependence of the vertical diffusion coefficient upon the external
conditions.
• Within the framework of the inverse problem the one-dimensional
stationary model of vertical exchange the Black Sea is constructed;
it includes dependencies upon the external conditions of the
advective vertical transport, the vertical diffusion coefficient and
the functions of sources-run-offs for the dissolved chemical
substances. The model results permitted to explain physically
presence of stationary quasi-thermal layer between 500 and 650 m .
• Physical mechanism of stabilization of the frontal zone of a
small-scale run-off lens on the tidal shelf.
• The fact of continuous "run-off" of the frontal zone of a
small-scale gravitational lens to the interface lower boundary is
revealed based on laboratory modeling.
• Narrow zone of intensive energy dissipation (downwelling zone) in
the fore-part of a gravitational lens in the conditions of the
near-surface stratification is revealed in natural conditions and
described within the framework of the theoretical model and
laboratory modeling.
• Based on the analysis of the model of climatic spectra of internal
waves in the ocean, the fact of dissipation of the wave field energy
in a narrow range close to the inertial frequency is independently
revealed. Earlier this result was obtained within the framework of
theoretical and numerical models taking into account non-linear
interactions in the wave field.
• The estimate of effective internal mixing ( Richardson dynamic
number) known from the results of laboratory modeling is obtained in
natural conditions.
• Structure of turbulent patches resulting due to the shear
instability of stratified flows is specified based of the field
measurements. It is revealed that natural patches possess
significant horizontal stratification.
• Experimental estimates of the characteristics of vertical mixing
in the ocean based on fine-structure advection spectra, salt fingers
and small-scale internal waves.
• Joint analysis of temperature, salinity and density spectra
permits to distinguish statistically quantitative contributions of
advection, internal waves and double diffusion convection to the
corresponding fine-structure dispersions.
• The compound model of the energy spectra of small-scale internal
waves is developed for comparison with fine-structure data. It
represents a combination of various weak-turbulent distributions.
• The calculated average characteristics of the vertical exchange
taking place due to small-scale non-linear waves and the processes
of double diffusion permits to carry out more detailed and
geographically lore local studies of the dynamics of water mass
mixing and the flows of various admixtures based on probing data
that is very important for the problems of ecological monitoring.
• Kinetic approach to the description of suspended sediment
particles motion in the coastal region is being developed. Based on
the probability function of particle settling velocity distribution
the corresponding distributions for a wide range of diameters of
terrigenous particles are being formed.
• The model of the vertical profile of suspended particles
concentration based on the relation between the probability
distribution parameters and the characteristics of a shallow water
surface wave velocity field is proposed.
• Requirements to the structure of the measurement system «Bottom
station» following from the theoretical studies are being
considered.
• Transport properties of the trapped topographic waves on shelf and
continental slope were explored. In the Bussinesque approximation
the middle flows induced by a wave due to nonlinearity are definite.
• Wave fluxes of heat, salt and, impulse in the area of a wave are
definite.
• The influence of small-scale turbulence on waves is studied;
coefficients of vertical turbulent exchange are estimated.
• It is shown that the horizontal turbulent exchange is of
substantial importance for the topographical waves trapped by the
sloping bottom as the horizontal shears of speed can be by an order
smaller than the vertical ones.
• Speed of wave energy dissipation resulted from the bottom friction
and the bottom mixed layer thickness is estimated.
• Tangential tensions at the bottom are definite. If the ground
tangential tensions exceed the critical values corresponding to the
beginning of motion of sediments , the wave stirs up the bottom
sedimentary material carrying out its transfer by middle flows indu
ced by waves due to nonlinearity.
• Ground concentration of sediments is defined. In the diffusive
approach vertical distribution of the wave-weighed sediments
concentration is obtained.
• Parameters of the trapped topographic waves observed in
northwestern part of the Black sea are calculated. The trapped
topographical waves were registered based on the temporal variation
of isolines of temperature, salinity and density.
• Amplitudes of the trapped topographical waves are defined.
• Spatial scales of the observed waves are calculated and dispersion
curves are constructed.
• Experimental data on the turbulent structure in sea surface layer
at different hydro- and meteorological conditions in near-coastal
zone of the Black Sea are obtained.
• The model for two-dimensional temperature convection of a roller
type is created. It permits to calculate intensity and depth of
penetration of convective motions based on the given heat flux and
the gradient of temperature in thermocline.
• Numerical model for calculating turbulent characteristics in sea
surface layer at weak and moderate winds without wave-breaking is
developed; the results of model calculations are in agreement with
the experimental data.
• Methods for calculating turbulent characteristics in the wave
affected layer with regard to the influence of wave-breaking of two
types – plunging breakers and spilling breakers – are elaborated;
the methods are based on the theory of turbulent jets.
For further information please contact:
Turbulence Department
Marine Hydrophysical Institute,
2, Kapitanskaya St., Sevastopol, 99011, Ukraine
Phone: 380-692-540452
E-mail:
turb@alpha.mhi.iuf.net
dep_turb@mail.ru
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