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Wyświetlanie 1-9 z 9
Tytuł:
Variability of Hydrodynamic and Lithodynamic Coastal Processes in the East Part of the Gulf of Gdańsk
Autorzy:
Ostrowski, R.
Pruszak, Z.
Skaja, M.
Szmytkiewicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/241442.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
sediment transport
waves
currents
deep-water climate
Opis:
The paper presents new findings concerning motion of water and sediment in the coastal zone of the east part of the Gulf of Gdańsk, from the Vistula River mouth at Świbno (Poland) to Cape Taran (Russia, Kaliningrad Oblast). The presented study deals with spatial variability of parameters of hydrodynamic and lithodynamic processes which have been subject to theoretical modelling. For the considered coastal segment, deep-water wave conditions reconstructed for a 44-year period have been analysed and transformed to the nearshore zone. Next, velocities of wave-driven longshore currents for the mean statistical year have been calculated, along with the longshore sediment transport rates. Regarding the net longshore sand motion, its detected direction is from Cape Taran towards the Vistula Spit. Very high annual rates of longshore sediment transport have been obtained for the coastal segment at Sambian Peninsula. These rates decrease considerably along the Vistula Spit, reaching zero at a distance of about one third of the Polish part of the Spit, measured from its root. At this location, the net longshore sediment transport (resulting from net longshore wave-current impact) reverses from westward to eastward.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2010, 57, 2; 139-153
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wind influence on the formation of nearshore currents in the southern Baltic: mumerical modelling results
Autorzy:
Sokolov, A.
Chubarenko, B.
Powiązania:
https://bibliotekanauki.pl/articles/241238.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
currents
waves
numerical modelling
coastal zone
Baltic Sea
Opis:
A two-dimensional numerical model was used for a simulation of vertical average longshore currents generated by both wind friction and wind-wave action in the nearshore zone. The modelling domain includes the southern part of the Baltic Proper (all boundaries were closed). Wind, uniform in space and varying in time, was the only forcing in the model. The correlation coefficient higher than 0.8 was obtained by model calibration versus the field measurements of currents conducted at the Lubiatowo field station (southern Baltic) during about 1.5 months in 2006. Comparative simulations of total currents including both wind-induced drift and wave components, and of total currents including only a wind-induced drift component, showed that the input of the drift component into currents in the nearshore zone is greater than commonly believed. Wind-induced drift strongly dominates outside the zone of wave transformation, and its input into the total resulting currents remains noticeable even in a zone between the shoreline and the depth of the first wave breaking. Thus, wind-induced drift constitutes up to 50% of the resulting longshore currents for longshore winds and no less than 20% of the longshore component of currents for winds at 45 degrees to the longshore direction.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2012, 59, 1-2; 37-48
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrodynamics and Lithodynamics of Dissipative and Reflective Shores in View of Field Investigations
Autorzy:
Ostrowski, R.
Pruszak, Z.
Skaja, M.
Szmytkiewicz, M.
Trifonova, E.
Keremedchiev, S.
Andreeva, N.
Powiązania:
https://bibliotekanauki.pl/articles/241380.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
cross-shore profile
waves
currents
grain size distributions
sediment transport
Opis:
The paper presents a comparative analysis of physical processes occurring at two different coasts, which belong to two different European seas. The first coast under examination comprises the sandy shore nearby Lubiatowo, located at the south Baltic Sea in Poland. The second site is represented by the sandy coast in Shkorpilovtsi, located at the west Black Sea in Bulgaria. Both sites are equipped with field research facilities ensuring extensive and precise in situ investigations. The study is focused on differences and similarities of hydro- and lithodynamics as well as the nearshore morphology between the above coastal zones. The present analysis is based on the results of the field campaigns carried out in recent years at the research facilities in Lubiatowo and Shkorpilovtsi. Considering the way in which wave energy transforms on the cross-shore profile, the sea shore at Lubiatowo is found distinctly dissipative while the shore at RB Shkorpilovtsi has a reflective character. This fact implies some differences in the features of wave-current motion and sediment transport.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2010, 57, 3-4; 199-218
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wind-Driven Currents and their Impact on the Morpho-Lithology at the Eastern Shore of the Gulf of Gdańsk
Autorzy:
Babakov, A.
Powiązania:
https://bibliotekanauki.pl/articles/241450.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
shore zone
wind
near-bottom currents
lithology
morpholithodynamics
sediment transport
Opis:
The paper presents results of a study of near-bottom currents, lithology and morphodynamics on the shore-zone of the Vistula Spit in Russia and on the western shore of the Sambian Peninsula. The measurements were conducted in 1991 and during the period of 2005-2009. The study involves the analysis of the synchronous and statistical parameters of the currents together with wind, grain-size and sorting coefficient distributions for the deposits of the beach and underwater slope, and also the analysis of the morphology and morphodynamics along the east coast of the Gulf of Gdańsk. It has been shown that under conditions of an acute angle between the seaward wind vector and the coastline the strongest and the most stable longshore currents are formed. An increase of the angle leads to a decrease of velocity and stability of these currents. Under conditions of the wind normal to the shore (90°) in the sector of the curved coast Yantarny - Baltiysk (west wind), convergence of the currents is observed. The assessments of annual capacities of the longshore sediment transport for the coastal segment at the Sambian Peninsula and the deformation volumes on the underwater slope at Baltiysk are summarized. A hypothesis is proposed that the sector of 5-15 km north of Baltiysk under the existing wind-wave conditions is the zone of convergence and the discharge-resulting sediment transport. The assumption of the prevalence of migratory and whirl circulations along the shore zone of Vistula Spit is put forward. It is noticed that entrance moles of Baltiysk considerably impact on parameters of the currents and flow of deposits along the coastline at the length of 3-4 km.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2010, 57, 2; 85-103
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Coastal Processes at Selected Shore Segments of South Baltic Sea and Gulf of Tonkin (South China Sea)
Autorzy:
Ostrowski, R.
Pruszak, Z.
Różyński, G.
Szmytkiewicz, M.
Ninh, P. V.
Quynh, D. N.
Lien, N. T. V.
Powiązania:
https://bibliotekanauki.pl/articles/241177.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
non-tidal and tidal coast
waves and currents
sediment transport
morphodynamics
Opis:
The paper presents a comparative analysis of physical processes occurring at two different coasts, which belong to two different geographic zones, namely a subtropical region exposed to monsoons and typhoons and a region of temperate climate with ice-snowy winter season. The former coast comprises sandy shores nearby Lubiatowo and the Hel Peninsula, located at the south Baltic Sea in Poland. The shore at Lubiatowo is relatively stable in the long run, while the shore along Hel Peninsula is mostly vulnerable to erosion and strongly protected by use of various measures (groins, seawall and artificial beach nourishment). The second site is the eroded (and partly protected by dikes) coast at Hai Hau in the Gulf of Tonkin (the South China Sea, Vietnam). This shore segment is built of mixtures of sandy and cohesive material, comprising both marine sands and river-borne sediments which nourish the coastal zone at the Red River mouth, located northwards of the Hai Hau beach. The present analysis is focused on differences and similarities of hydro- and morphodynamics between the above coastal zones in various time and spatial scales. The analysis shows that regional climatic and environmental conditions, associated with geographical zones, play a key role in dynamic evolution of the coastal regions and necessitate different engineering activities against erosion and flooding.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2009, 56, 1-2; 3-28
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Uncertainties in Determination of Sediment Transport Rates in Coastal Regions
Autorzy:
Ostrowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/241200.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
waves
wave-driven currents
bed shear stresses
friction velocity
sediment transport
Opis:
The paper deals with research uncertainties, difficulties, inaccuracies and unreliabilities related to the modelling of physical phenomena involving coastal lithodynamics. The considerations are focused on processes of wave transformation, wave-driven currents and sediment transport itself. It is shown that possible inaccuracies at individual stages of the modelling of coastal hydrodynamics can lead to serious uncertainties with respect to the ultimate modelling output, namely bed shear stresses and sediment transport rates. These inaccuracies result mostly from arbitrarily assumed parameters and constants. Other modelling biases discussed in the paper comprise simplifications and approximations with respect to sediment resources and size-graded properties, randomness of hydrodynamic impacts, bottom roughness and land-borne factors involved in coastal lithodynamics.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2016, 63, 4; 265-280
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Case-Study Modelling Analysis of Hydrodynamics in the Nearshore of the Baltic Sea Forced by Extreme Along-shore Wind in the Case of a Cross-shore Obstacle
Autorzy:
Sokolov, A.
Chubarenko, B.
Powiązania:
https://bibliotekanauki.pl/articles/241305.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
numerical modeling
extreme weather
storm surge
wind waves
currents
protective dam
Gulf of Finland
Opis:
In the current study we use a three-dimensional model with hydrodynamic and spectral wave modules operating in a coupled mode to simulate the response of currents and wind wave fields to winds of 20–25 m/sec offshore of the protective structure of the Saint Petersburg Flood Prevention Facility Complex. The model was calibrated against field data, which allowed us to obtain a tool describing storm situations in the eastern part of the Gulf of Finland with a satisfactory accuracy. The numerical modeling showed that the protective dam did not have a noticeable effect on the levels of stormsurge, significantwave height, or current speed in areas seaward of the dam. The increase in erosion processes on the southern shore of the easternmost part of the Gulf of Finland in recent past has most probably been related to other factors. We found that if a west or south-west wind of at least 25 m/s blows over the Baltic Sea for at least 16 hours, the level of storm surges seaward of the dam may reach 3 or more meters. An artificial strengthening of the coastline and the creation of shore protection structures are recommended.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2018, 65, 3; 163-176
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Wave Shape on Sediment Transport in Coastal Regions
Autorzy:
Ostrowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/241268.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
wave shape
nearbed free stream velocities
wave-driven currents
cross-shore sediment transport
longshore sediment transport
Opis:
The paper deals with the influence of the wave shape, represented by water surface elevations and wave-induced nearbed velocities, on sediment transport under joint wave-current impact. The focus is on the theoretical description of vertically asymmetric wave motion and the effects of wave asymmetry on net sediment transport rates during interaction of coastal steady currents, namely wave-driven currents, with wave-induced unsteady free stream velocities. The cross-shore sediment transport is shown to depend on wave asymmetry not only quantitatively (in terms of rate), but also qualitatively (in terms of direction).Within longshore lithodynamics, wave asymmetry appears to have a significant effect on the net sediment transport rate.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2018, 65, 2; 73-90
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sediment transport beyond the surf zone under waves and currents of the non-tidal sea: Lubiatowo (Poland) case study
Autorzy:
Ostrowski, R.
Stella, M.
Powiązania:
https://bibliotekanauki.pl/articles/241109.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN
Tematy:
wave-induced nearbed oscillations
sea currents
wind-driven current
sand grain diameter
bed shear stress
friction velocity
sediment transport
Opis:
The paper deals with the sandy coastal zone at Lubiatowo in Poland (the south Baltic Sea). The study comprises experimental and theoretical investigations of hydrodynamic and lithodynamic processes in the coastal region located close to the seaward boundary of the surf zone and beyond the surf zone. The analysis is based on field data collected at the IBW PAN Coastal Research Station in Lubiatowo. The data consist of wind velocity reconstructed from the long-term wave climate, deep-water wave buoy records and sea bottom soil parameters. Nearbed flow velocities induced by waves and currents, as well as bed shear stresses are theoretically modelled for various conditions to determine sediment motion regimes in the considered area. The paper discusses the possibility of occasional intensive sediment transport and the occurrence of distinct sea bed changes at bigger water depths.
Źródło:
Archives of Hydro-Engineering and Environmental Mechanics; 2016, 63, 1; 63-77
1231-3726
Pojawia się w:
Archives of Hydro-Engineering and Environmental Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-9 z 9

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