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In this study generation, propagation and run-up of tsunami waves caused by submerged landslide are studied in two dimensions. The governing equations, Navier–Stokes equations, are solved in a Lagrangian form using a mesh-less numerical method by the name of Incompressible Smoothed particle hydrodynamics with a prediction–correction step. The Comparison of the result of this study with experimental data indicates that the deviations between the wave amplitudes are less than 5 cm for every different time steps and also, this model simulated run up and Water surface fluctuations more accurately against the Nasa-Vof until to 3 seconds.

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The aim of this study was to design and develop a three-dimensional numerical baroclinic model with the ability to accept complex bottom topography and variable wind in space and time to investigation wind-induced current at 10 layers in the south Caspian Sea. The finite difference method Was used for numerical solution of the primitive equation in spherical Sigma pressure coordinate system on staggered modified Arakawa C grid. The wind data available from ECMWF ERA 15 data sets and the bathymetric data obtained from the JEBCO data sets with spatial resolutions of 0.125^o were utilized in the model. The result shows there are found a cyclonic eddy in middle of the basin and an anticyclonic current in close of the western coast that continued over the year. In addition, the circulation in the extensive continental shelve near the eastern coast is especially sensitive to wind direction and speed Also the maximum of surface current always take place in this area.

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In order to numerically simulate transmission of oil spilled in Caspian Sea from Turkmenistan oil fields, wind induced currents in the sea were simulated using an unstructured grid Finite Volume Community Ocean Model (FVCOM) in the summer and spring of 2012. The results of the model in the fall season were then compared to the measured data for surface currents in three stations of Astara, Roudsar, and Amirabad. Comparison of the measured data and the current model output revealed that implementing turbulence closure module produces more accurate results than when the module was excluded. Later on, in order to determine the destination for the oil spilled from Turkmenistan oil fields, the output of flow model was imported into the GNOME computer application along with 6-hourly wind time series. Turkmenistan’s oil wells on the eastern shores of the southern fields of the Caspian Sea in front of the Cheleken Peninsula were considered as the location of oil pouring. The type of pouring was momentary and the volume of oil pouring in each well was 100 barrels. Simulation of trajectory of spilled oil was conducted based on different pouring time and the location of the oil spill hitting the shore were acquired. Comparing the results from simulation and location of collecting oil spills in August 2012 demonstrates acceptable accuracy; thus, it could be said that, it is quite feasible that oil spills from Turkmenistan oil fields could reach the shores of Iran in the summer.

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One of the most important issues in designing a submarine is calculating its resistance and power. It is still a scientific challenge to calculate and generalize the results from a scaled model to the main vessel. In this study, the effect of the scale in a numerical method on the resistance coefficients of a submarine, including the total, friction and pressure resistance coefficients, has been investigated by numerical simulation method. Also, the accuracy of the results of the existing empirical relationships for calculating submarine resistance coefficients has been evaluated. The SUBOFF submarine model was used to conduct studies. The results show that the existing empirical relationships enable the calculation of the friction coefficient with an error of less than 10%, the pressure coefficient with an error of less than 30%, and the total drag coefficient with an error of less than 8.5%.