Analysis of the impact of winds, tide oscillations and density distribution on the sea exchange through culverts in the marinas as exemplified by the Ičići marina

Prikazani su rezultati provedenih 3D numeričkih simulacija cirkulacije i izmjene mora s ciljem kvantifikacije doprinosa cijevnih propusta u izmjeni mora iz akvatorija marine s morem iz okolnog područja. Osim djelovanja vjetra i plimnih oscilacija u numeričkom modelu uvažena je i prostorno/vremenska promjenjivost temperature i saliniteta u profilima otvorenih granica modela, propusta i ulaza u marinu. Prvotno je analizirana marina hipotetskih geometrijskih obilježja: duljina 300m, širina 150m, varijabilne dubine od 3 do 7m. Varirana je širina ulaza u marinu (25m i 50m), pozicije cijevnih propusta (4 pozicije), smjer i brzina vjetra (N, NE, E, SE, S, SW, W, NW ; 1, 3, 5 Bf), geografska lokacija (sjeverni jadran – Rovinj ; južni jadran – Dubrovnik), doprinos gradijenta gustoće mora. Nastavno su provedene numeričke simulacije za marinu Ičići, uzimajući u obzir stvarnu geometriju zaštitnih građevina (lukobrana), realistične oceanografske uvjete (dubine, dinamika morskih razi, temperatura i salinitet mora) i djelovanje vjetra. Temeljem dobivenih rezultata predložena je i praktična metodologija za izbor pozicije cijevnih propusta u tijelu zaštitne građevine marine.The paper presents the results of the conducted 3D numerical simulations of the sea circulation and exchange with the aim to quantify the contribution of pipe culverts to the sea exchange from the marina area and the surrounding sea. In addition to wind action and tide oscillations, the numerical model also takes into account the spatial/temporal changes in temperature and salinity in the profiles of open boundaries of the model, culverts and the marina entrance. Initially, a marine of hypothetical geometric characteristics was analyzed – with a length of 300m, width of 150m and variable depth of 3 - 7m. The following elements were varied: the width of the marine entrance (25m and 50m), positions of pipe culverts (4 positions), wind direction and velocity (N, NE, E, SE, S, SW, W, NW; 1, 3, 5 Bf), geographical location (northern Adriatic – Rovinj; southern Adriatic – Dubrovnik) and the contribution of the sea density gradient. Following this, numerical simulations were conducted for the Ičići marina by taking into consideration the actual geometry of the protection facilities (breakwater), realistic oceanographic conditions (depth, sea level dynamics, sea s temperature and salinity) and wind action. Based on the obtained results, a practical methodology for selecting the positions of pipe culverts in the structure of the marina protective facility was also proposed