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EN
This paper presents details of 37 storm surges that occurred on the Polish southern Baltic Sea coast in the autumn/winter 2021–2022 season. They emerged during the passage of a larger number of low-pressure systems than usual from the SW-W direction over the Baltic Sea. Based on an assessment of meteorological and hydrological conditions during the storms, the relationship between the wind parameters, the sea level increase, and its maximum elevation was ascertained. The relationship between the sea level and the run-up elevation was ascertained. The elevation of the sea level and run-up on the onshore were compared with the beach height. Sections with a lower beach were affected by dune erosion already at a lower sea level. The dependence of dune erosion on the sea level elevation was presented. The value of the dune base retreat depended on the beach elevation and the sea level expressed by the onshore flow called run-up. The most significant erosion occurred during the storm Nadine with a sea level of 1.0–1.28 m AMSL. The average erosion varied between 1.0 and 4.5 m. The maximum erosion values reached 8–13 m.
EN
Ship manoeuvrability is a wide term which consist of number of various parameters. Knowing the influence of these parameters on ship manoeuvrability is a first condition to ensure and maintain safe navigation. However, many of these parameters are external forces and, in some cases, cannot be calculated and prediction may be complicated. Analysing the influence of external forces can give as an insight into ship manoeuvrability when such external force occurs. The main purpose of this paper is to analyse the influence of wind on ship manoeuvrability. The best way to make such analysis is during turning circle because in this case wind acts in all 360°. Analysis is made using empirical equations and in situ with the real vessel. The results provide the better understanding of vessel trajectory and show that in some cases vessel may respond in unexpected manner.
3
Content available Wind affecting berthing operations
EN
Almost every voyage culminates in a manoeuvre to berth the ship safely along a quay or wharf. During this phase a ship is affected by a number of factors, one of them being wind. This paper seeks to understand how wind affect a ship in regards of power consumption during berthing. A field study was conducted on a car passenger ferry, where every approach in one harbour was logged and analysed over a period of four months. The goal was to provide greater knowledge about energy usage and the study presents several interesting findings. It is estimated that power consumption is stable when the median wind speed is less than 4 m/s. Stronger winds have a significant effect on power consumption, e.g 17 m/s gives an 106,31% increase from calm conditions. Furthermore there is not discovered any correlation between consumption and wind direction in this study.
EN
Effective maritime rescue bases on both surface units and aviation. The different types of units are selectively chosen according to their performances. The main operational limitations of a particular unit are weather conditions and vehicle characteristics. In addition to standard units, for purposes of search and rescue, a WIG craft is also applicable. The craft uses so called Ground Effect, therefore is characterized by relatively high speed and low fuel consumption. The article attempts to determine the statistical operational effectiveness of different search and rescue units. The analysis is based on data on wind force and direction, in the period from May to October, in the west coastal zone of Poland. The results of the study allow to compare operational effectiveness of various rescue units. The findings can be used to support planning of search and rescue forces’ dislocation and their efficient use.
PL
Efektywne ratownictwo morskie wykorzystuje zarówno jednostki nawodne, jak i lotnicze. Ze względu na swe właściwości eksploatacyjne poszczególne typy jednostek są selektywnie dobierane do aktualnej sytuacji. Głównymi ograniczeniami operowania daną jednostką są warunki pogodowe oraz cechy pojazdu. Do celów poszukiwania i ratownictwa, oprócz standardowych jednostek, zastosowanie znaleźć mogą również ekranoplany, czyli pojazdy wykorzystujące efekt przypowierzchniowy. Pojazdy te wyróżniają się relatywnie dużą prędkością oraz niskim zużyciem paliwa. W artykule podjęto próbę określenia statystycznej skuteczności operacyjnej poszczególnych jednostek ratowniczych. Analiza bazuje na danych dotyczących siły wiatru w okresie od maja do października w zachodniej strefie brzegowej Polski. Rezultaty badania pozwalają na porównanie stopnia skuteczności operacyjnej różnych jednostek ratowniczych. Wyniki mogą posłużyć do wspomagania planowania rozmieszczenia sił służb ratowniczych oraz ich efektywniejszego wykorzystania.
EN
The study assesses the accuracy of 24-hour weather forecasts on the Klaipeda (Lithuania) - Bayonne (France) navigational route emitted in NAVTEX system. There were analysed the parts of the forecasts concerning wind direction and force, visibility and precipitation. The verification was based on the real state of these factors, stated the next day on areas concerned. A high degree of forecast accuracy was stated in all five broadcasting stations of the NAVTEX system, particularly with reference to visibility and precipitation.
PL
Artykuł przedstawia metodykę wyznaczania współczynników sił aerodynamicznych statku z wykorzystaniem numerycznej dynamiki płynów. Obliczenia numeryczne zostały zweryfikowane z wynikami uzyskanymi w tunelu aerodynamicznym. Pokazano również sposób ułożenia siatki i jej późniejszej adaptacji w celu dopasowania jej do lokalnych warunków przepływu. Duży nacisk w prezentowanej metodyce obliczeń położono na ograniczenia czasu generowania siatki i automatyzację procesu obliczeń.
EN
The paper presents guidelines for the determination of ship aerodynamic forces with the application of computational fluid dynamics methods. Numerical calculations were verified against the results from the wind tunnel. The techniques of grid making and furhter grid adoption for local flow characteristics were discussed. Special attention was paid to the problems of time limitations during grid generation and automation of thge computation process.
PL
Na koncentrację zawiesin w wodzie morskiej wpływa wiele czynników. Są to między innymi: odległość od ujścia rzeki, budowa geologiczna brzegu i dna morskiego, kierunek i prędkość prądów pływowych i dryfowych oraz stopień sfalowania morza. Przedstawiono wyniki badań pokazujące wpływ siły wiatru na zjawisko sedymentacji w przybrzeżnych obszarach zbiorników wodnych.
EN
There are many factors which influence the concentration of suspension in sea water. These includethe distance from the estuary, geological structure of the shore and seabed, direction and speed of tidal current and drift, as well as wave height. The results of research presented in the article show the effect of the wind force on the sedimentation in offshore areas of water reservoirs.
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