Lidiia Tereshchenko

Institute of Hydromechanics National Academy of Sciences of Ukraine Kyiv Ukraine · Hydrodynamics of wave and channel flows

The paper presents the results of experimental research and comparison of traditional and non-traditional grynes design. Based on experiments, it was found that in the inter-buoy space for groyne of traditional design, the elevations and width of the natural beach are not sufficient to preserve the beach surface under the action of waves at the sur...

Групові конструкції погано обтічних тіл широко використовуються у мостобудівній практиці. Сполучені течії таких конструкцій характеризуються значною складністю, нестаціонарністю та нестійкістю. В околі погано обтічних тіл формуються системи підковоподібних вихрових структур, зсувні шари, відривні області, струменеві течії, слідні вихори та вихрові...

Спряжена течія – це класична проблема механіки рідини та газу, яка має широке застосування в аеро- да гідродинаміці. Спряження крила з фюзеляжем літака, виступаючих конструкцій на корпусах суден, автомобілів, лопаток турбін на їх корпусах, опор мостових переходів на дні водоймищ та багато інших широко застосовується у практичній діяльності людства...

This paper presents the results of mathematical and physical modeling of the interaction of waves with the wave chamber on cylindrical supports and the upper part in the form of a permeable waterfront. On the basis of the diffraction model the mathematical modeling of refraction and transformation of waves near the structure is carried out. In the...

The increase in freight traffic between central and northern European countries and the countries of the Black Sea coast requires an increase in shipping along the Danube River. The Danube is the seventh international transport corridor, which unites the countries of Europe and Asia. The deepening of the Bystrii estuary of the Kiliya’s delta of the...

Results of numerical and physical simulations of a junction flow around a three-row cylinder group mounted on the rigid, hydraulically smooth flat surface are presented. Numerical model is based on the vortex method used to integrate 2D Navier–Stokes equations. Experimental researches are carried out in the open hydraulic channel where color inks a...

Pile groups and complex piers have become more popular in the construction of bridge crossings due to economical and geotechnical reasons. The interaction of bridge piers of various structural solutions, which are in the wake one after another, leads to significant discontinuity and non-linearity of the flow between the piers, and also significantl...

The use of renewable energy sources is urgent and relevant in the life of humanity in the current conditions of fuel and energy crisis and environmental pollution. One type of renewable energy source is tidal power plants, which use the potential energy of tides. Determining the features of the interaction of the wave flow with the designs of the t...

A semi-empirical technique for calculating the parameters of wind waves at variable sea depths along the wind acceleration has been developed and presented. This technique allows you to determine the average values of wind wave heights, their length and period depending on the wind velocity, taking into account and without taking into account the h...

The formation of thrombi on the streamlined surface of the bileaflet mechanical heart valves is one of the main disadvantages of such valves. Thrombi block the valve leaflets and disrupt the cardiovascular system. Diagnosis of thrombosis of the bileaflet mechanical heart valves is relevant and requires the creation of effective diagnostic tools. Hy...

One of the important tasks for Ukraine is to restore navigation on the mouth of the Danube Bistre, using it as a European-Asian way from the Baltic Sea to the Black Sea, and then to the East. Restoration of the deep-sea navigation of the Danube-Black Sea River has begun about ten years ago and has been progressing with great difficulty and interrup...

Головним чинником руйнування берегової зони є хвилева абразія, активація якої спричинена підвищенням рівня моря, збільшенням повторюваності та інтенсивності штормів, безсистемним і необґрунтованим будівництвом берегозахисних і берегоукріплювальних споруд та іншими чинниками. Заходи з будівництва берегозахисних споруд належать до природоохоронних і...

Прибережні зони морів та океанів відіграли та продовжують грати видатну роль у розвитку людства, але й піддаються значній дії метеорологічних та геофізичних факторів, які змінюють ці зони та стимулюють проводити великі роботи по захисту від дії негативних компонентів цих факторів. Серед негативних факторів прибережної зони є дія вітрових хвиль. Дія...

Experimental research results of hydrodynamic noise of pulsating flow through a bileaflet mechanical mitral valve are presented. The pulsating flow of pure water corresponds to the diastolic mode of the cardiac rhythm heart. The valve was located between the model of the left atrium and the model of the left ventricle of the heart. A coordinate dev...

It’s found that in stream conditions of pure water, the integral characteristics of the pressure field are lower than in stream conditions of the aqueous glycerin solution. With increasing glycerin concentration in the solution, average pressures and especially rms pressure fluctuations are increased. The mean values of pressure and rms values of p...

A semi-empirical method for calculating the parameters of wind waves at variable depths of the sea along the overclocking, which allows to determine the average values of the heights of the wind waves, their length and period depending on the wind velocity with and without taking into account the wind surge, has been developed and described. Within...

The results of mathematical and physical modeling of structures of engineering protection of the closed water area for the parking of boats and yachts are presented. The closed water area is formed by the construction of a protective mole with a wave protective cape from tetrapods. It is revealed that wave height and wave loads on structures decrea...

Results of experimental researches of formation and development of local and global scours near to bridge piers are submitted. Influence of an ar-rangement of two bridge transitions which are in a wake one after another, on physics of the formation process scour is shown. The scour before pris-matic pier is caused by interaction of the horseshoe vo...

The results of physical modeling of recreational beach protection by active protection methods are presented. The experiments were carried out in the wave pool on models of intermittent T-shaped and V-shaped breakwaters with traverses and groyne systems. The use of active shore protection methods makes it possible to preserve natural and artificial...

The results of physical modeling of recreational beach protection by active protection methods are presented. The experiments were carried out in the wave pool on models of intermittent breakwaters with T-shaped and V-shaped traverses and dike dam systems. The use of active shore protection methods makes it possible to preserve natural and artifici...

Experimental results of hydrodynamic noise of the jet flow across an open and semi-closed bileaflet mechanical heart valve were analysed in the paper. The vortex and jet flows behind prosthetic heart valve are non-linear, random processes. Such processes are analyzed using the methods of mathematical statistics and probability theory. Processing an...

The vortex and jet flow behind an open and semi-closed bileaflet mechanical heart valve is a non-linear, random process. Such processes are analyzed using the methods of mathematical statistics and probability theory. Processing and analysis of the experimental results of measuring the field of pressure fluctuations, hydrodynamic noise near the mit...

This article presents the experimental result and mathematical analysis influences of the permeable breakwaters to dynamics of the coast on various conditions by the action of waves. Deposition of sediment behind breakwaters leads to the formation tombolo of a certain size and intensity depending on the parameters of breakwater and the presence of...

The paper presents the results of experimental research of hydrodynamic noise of pulsating flow through a bileaflet mechanical mitral valve. The pulsing flow corresponds to the diastolic mode of heart work with a cardiac rhythm of 60 beats per minute. Experimental studies of the flow of pure water.

Представлены результаты экспериментальных исследований гидродинамического шума, генерируемого струйным течением через механический двустворчатый про- тез митрального клапана итальянской компании Sorin Group. Физическое модели- рование проведено в лабораторных условиях на модели камеры левого предсердия и камеры левого желудочка сердца. Обнаружено,...

The paper deals with presenting of results of experimental study of a hydrodynamic noise generated by jet flow through a mechanical bileaflet prosthetic mitral valve produced by the Italian company Sorin Group. A physical modeling is carried out in vitro on the model of the left atrium chamber and left ventricle chamber. It is found that the highes...

The results of experimental studies of sounds and noise of a mechanical beleaflet heart valve are presented in the report.

The experimental result and mathematical analysis influences of the permeable breakwaters to dynamics of the coast on various conditions by the action of waves. Deposition of sediment behind breakwaters leads to the formation tombolo of a certain size and intensity depending on the parameters of breakwater and the presence of a weak along-shore sed...

Background. Numerical simulation and experimental research have been used as powerful tools to understand and predict the behavior and mechanics of the operation of natural heart valves and their prostheses in natural and pathological conditions. Such studies help to evaluate the effectiveness of the valves, their design and the results of surgical...

Experimental result of wave influence on submerged breakwater. The quality of protection by means of submerged breakwater depends on the geomorphology of the underwater coast, geometry and the shape of the construction. The experiment included: 1) experiments with single of submerged breakwater , constant of submerged and variation of the width of...

The results of experimental researches of the pressure field acting on the flexible screen linen of the training construction model, projected for the water area of Tashlyk cooling pond of South-Ukraine nuclear power station are presented. Maximum dynamic pressure acting on the screen linen is observed in the surface layer flow. The power spectral...

Lots of mouths of rivers that flow into the seas or large lakes, estuaries and reservoirs, are complex hydrodynamic structure under the influence of sea and river factors. Therefore, the study raises many complex issues to assess the storm surge, wind waves and analysis of field observations and theoretical solution as a result of problems with phy...

In this article the results of experimental research of kinematics and the dynamics of horseshoe vortex structures, wake vortices and lateral jet flows, formed around and inside the pile group of three-row grillage, set on a flat rigid surface and sand soil, are presented. Visualization of flow is conducted using water soluble coatings and contrast...

Over 55% of heart valve replacements use mechanical heart valves, with bileaflet heart valves currently the most popular design [1]. The fluid dynamics of mechanical valves may differs substantially from those of native valves. Flow is eccentric in monoleaflet valves and composed of 3 separate jets in bileaflet valves. The study of ventricular flow...

4D flow MRI can be used to visualize in-vivo blood flow in several complex cardiovascular diseases, e.g. aortic coartaction-dissection and valve stenosis. However, clinical usability and post-processing of 4D flow data is still an open issue. In this paper we present a new segmentation algorithm based on flow features at peak systole. This algorith...

Magneto-soft ferromagnetic materials which are characterized by low losses of high permeability are widely used at different medical devices. Ferromagnetic applied as part of device can contain different heterogeneities types such as cavities, structural or technologic inclusion or hole. We investigate the strength and durability of these structura...

To simulate wind waves and storm surge in the area of spit Curve located in Taganrog Bay of the Azov Sea used model SWAN, based on the numerical solution of wave energy balance equation in spectral form. The calculations used SWAN version 40.85 in the steady state . The angular resolution of the model was 10º. For coordinate frequency varying from...

The results of experimental investigations of the interaction of surface solitary waves with steep slopes are presented. It is found that long wave which move upward (run-up) the slope without breaking may break during rundown. The values of maximum wave run-up and rundown of solitary wave for steep slopes have been obtained. The relation of the va...

Consider the results of mathematical modeling of wave loading on bulk approaches bridge across the reservoir of the Kyiv hydroelectric station. Numerical calculations of wind waves, reaching the body of the projected bridge transition for all waves of dangerous wind directions and water level on the Kyiv reservoir, have been carried out. On the bas...

The results of mathematical modeling of wave loading on natural beaches and gentle slopes bank protection structures.

In the case of deep trial run on bars of the mouth Novostambulskoho Kyliyskoyi Danube Delta in article features the calculation of wave mode on the fairway with challenging conditions approach.

The problem of transformation of waves over the underwater penetrating inclined berm, which is the basis for artificial gravel-pebble and sandy beaches, is considered. Which connects of the berm to vertical or inclined types of coastal protective structures. The latter are used as structural elements of slopes of artificial areas of the coastal zon...

This article considered solve the stress-strain state unlimited magneto-soft ferromagnetic, with laminated ellipse and is unde the action of homogeneous external magnetic field.

This article considered the stress-strain state unlimited magneto-soft ferromagnetic, which contains elliptic hole and is under the action of homogeneous external magnetic fields solve in an environment Марle

The problem of modeling of wind-wave diffraction for extended gravity type breakwater made of metal shells, which is located in the rear area of the container terminal artificial bounded from the front edge of the shore as a vertical sheet pile wall. On the front sides of the terminal area is limited sloping shore protection structure of tetrapods.

Human economic activity is manifold in shore and manifests itself in the different aspects. The majority part of the activity is connected with the use of water resources of the natural and artificial water areas, and also with the control of damage effect of water, i.e. with the hydrotechnical and engineering aspects. The growth of anthropogenic i...

We consider the results of mathematical and physical modeling of the dynamics of bar section of the mouth of the sleeve Bystryi Kyliyskoyi Danube Delta in the area of marine approach Danube-Black Sea

The results of experimental researches of factors of dynamics of on-shore sandy slope are presented under act of wind waves. The experiment was conducted on water space dike dam models. The variants are as following: the free shore (natural conditions); coast, protected the system of impenetrable groins; coast, protected the system of groins with t...

This paper is devoted to the experimental researches of formation and development of a local sediment scour near a bridge piers which are in a wake one after another. The mechanism of the local sediment scour formation before the bridge piers is submitted and physical processes of formation and development of the vortex systems around of the bridge...

The paper addresses a stress–strain problem for an infinite soft ferromagnetic body with an elliptic inclusion. The body is in a homogeneous magnetic field B 01. The basic stress–strain characteristics and induced magnetic field in the body and inclusion are determined and their features in the neighborhood of the inclusion are studied. The magneto...

A stress–strain problem is solved for an infinite isotropic magnetically soft body containing an elliptic inclusion. It is assumed that the body is in an external magnetic field. The basic characteristics of the stress–strain state and the induced magnetic field are determined and their features at the inclusion are analyzed. Graphs are drawn for t...

The problem on the stress–strain state of an infinite isotropic body made of a magnetically soft material and containing a spherical cavity is considered. It is assumed that the body is under an external magnetic field. The basic characteristics of the stress–strain state and the magnetic field induced are determined and their singularities near th...

The paper deals with the problem on the stress-strain state of an infinite isotropic body of a magnetically soft material containing a spherical cavity. It is assumed that the body is under the action of an external magnetic field. The principal characteristics of the stress-strain state, as well as of the magnetic field induced are determined and...