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Maritime transportation is taken into account as an environmentally friendly transportation option. Approximately 90% of the world trade is done by sea transportation and growing of globalized world conditions increase shipping and port emissions. The use of heavy fuels on ships and the positioning of port areas close to the habitats affect the health of people living in coastal cities. Accordingly; NOx, SOx, PM and CO2 emissions are especially limited for international regulations by International Maritime Organization (IMO) and the European Union (EU). In this study, real-time air quality measurements of PM2.5, PM10, SO2, CO, NO and NO2 emissions are performed for three months where the measurement tool is located in the Port of Ambarlı, Marport Terminal. The ships are monitoring during berth and manoeuvring around the critical dates and times at the terminal. The hourly values of real-time emission data measurements are shown for 25 May to 15 August 2017. Critical dates and times which are the highest value of the all emissions are determined between measured dates. SO2, NO, CO and CO2 emissions are investigated for different wind speeds using a single ship positioned at different angles and two ship models in different operating modes via Computational Fluid Dynamics (CFD) modelling.

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Roll motion is still a challenging problem in naval architecture and an adequate prediction of this physical phenomenon is important because of its undesirable effects such as capsizing. There are several methods using linear potential theory to predict roll motion, such as strip method, however, the accuracy of the calculated results lag behind the accuracy of other degrees of freedom due to viscosity. Viscosity have an important effect on roll damping, especially near resonance, and as it is known, it is not included in potential flow methods. Vortex shedding is the main physical phenomena in viscous damping of the roll motion and it affects the flow velocity around the bilge. This may lead to pressure increase or decrease on the hull. In the present study, roll damping of a forced rolling hull with bilge keels at different roll amplitudes was calculated numerically by using an Unsteady Reynolds-averaged Navier-Stokes (URANS) solver. For the purpose of validation, forced roll experiments were carried out and the results were plotted next to numerical results. The generated vortices around the hull and bilge keel were observed in the URANS calculations. In the case of large roll amplitude motion, the vortex shedding from the bilge keel interacts with the free surface and leads to decrease on roll damping.Numerical and experimental calculation of roll amplitude Ahmet Yurtseven, Toru Katayama effect on roll damping