Iranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201A Comparison of the Dynamic Response of a Product Transfer System in CALM and SALM Oil Terminals in Operational and Non-Operational Modes in the Persian Gulf region11414935410.22034/ijcoe.2021.149354ENEsmaeil HasanvandOffshore Structure Engineering Department, Petroleum University of Technology, AbadanPedram EdalatMechanical Engineering Department, Petroleum University of Technology, AbadanJournal Article20220506Offshore oil terminals are a cheaper and safer solution than conventional shore terminals for unloading and loading tankers. There are several types of offshore terminals, including Catenary Anchor Leg Mooring (CALM) and Single Anchor Leg Mooring (SALM). Product transfer systems, including floating and underwater pipes, are the most important components of these terminals. The present study aims to compare the dynamic response of a product transfer system in these two models of offshore oil terminals. To obtain structural responses, including forces created in floating and underwater pipes, a simulation in Orcaflex software is used considering wind, current, and wave forces in different sea states. The curvature and tension in the pipes are considered a criterion for evaluating the failure modes. The results show that under operating conditions, the curvature and effective tension of the pipes in the SALM terminal are 5% and 93% lower than those in similar operating and environmental conditions in the CALM terminal, respectively. As the environmental conditions increase up to Sea State 8, when the tanker is not connected to the terminal, the SALM terminal pipes will have more structural stability and usability, while the CALM terminal pipes will only have stability up to Sea State 6. The tensions generated in the pipeline end manifold (PLEM) of the SALM terminal are also lower than those in the CALM terminal. It is also observed that the critical point for the CALM terminal pipes is the connection point to the terminal buoy, while it is the connection point to the seabed for SALM terminal pipes, which should be considered in designing a product transfer system for this type of terminals.https://www.ijcoe.org/article_149354_9fa5779458b7c1f1e578e312b9281c6f.pdfIranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201The impact of the inlet cyclones to the Caspian Sea on the sea level fluctuations152814935510.22034/ijcoe.2021.149355ENNegin Hatami BavarsadCollege of Marine Sciences, Tarbiat Modares University, IranDariush MansouryCollege of Marine Sciences, Tarbiat Modares University, Iran0000-0003-4190-4498Mohammad Reza KhalilabadiFaculty of Naval Aviation, Malek Ashtar University of Technology, Shiraz, Iran0000-0002-7000-1848Mohammad MalekilonbarCollege of Marine Science, Tarbiat Modares University, IranJournal Article20220506In this article, source and trace of the cyclones produced on the Caspian Sea were investigated from 2012 to 2017. The required data for this research consists of water level data recorded at stations such as Amirabad port, as well as other ports, mean atmospheric pressure at the Sea surface and wind data from ECMWF Web site. Results show that source of atmospheric low pressure is from the southwest and west of the Caspian Sea and in 2016 it is from the northern region of this basin. These atmospheric low pressures mostly enter to the Caspian Sea from the northwest of the mid Caspian Sea and their moving trace is to the east and southeast of the southern Caspian Sea. With the investigation of the impact of atmospheric low pressure and wind on the water level of Caspian Sea, in the coasts of Bandar-e Anzali, Fereydunkenar and Amirabad, it was obtained that in 2013 and 2016 low pressure effect and in 2015 wind effect was the most effective phenomena on the water level. The maximum movement velocity of the atmospheric cyclones from 2012 to 2017 was respectively equal to 10.17, 7.96, 44.7, 16.7, and 2.6 m/s.https://www.ijcoe.org/article_149355_8d7a9257e0e29491b1aa77e623d72e8c.pdfIranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201Evaluation of the Soil Properties Effect on Upheaval Buckling of Subsea Pipelines293514935610.22034/ijcoe.2021.149356ENAbdolrahim TaheriPetroleum University of TechnologyMehdi TasdighiPetroleum University of TechnologyJournal Article20220506Different parameters contribute on the upheaval buckling of subsea pipelines. Seabed is a surface that pipeline contact with it directly. So seabed is one of the most important parameters in the upheaval buckling of subsea pipeline. Subsea pipeline includes imperfection shape and characteristics of the seabed soil. In this paper, different soil types are considered for seabed and modeled with ABAQUS standard code. Seabed is modeled as a two-dimensional springs. The task of these springs is to react like soil against forces. The calculation of spring stiffness is based on standard code of American Lifelines Alliance. The critical stress increases due to the soil cohesion increasing. Soil cohesion is more effective parameter than soil angle friction of the soil. In this study, the effect of temperature difference is evaluated for different types of soil. 10 difference temperature is considered for this evaluation. 50 ℃ to 110 ℃ is the range of mentioned temperature. The effect of difference temperature on the upheaval buckling increases due to increasing of angle friction.https://www.ijcoe.org/article_149356_d83f9d23a7e848b1ddb77cca990adb53.pdfIranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201A Hydrodynamic Model of Tidal Current in the Strait of Hormuz374514935710.22034/ijcoe.2021.149357ENMehri FallahiFaculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, IranMasoud Torabi AzadDepartment of Physical Oceanography, Islamic Azad University, North Tehran Branch, Tehran, Iran0000-0003-0130-4279Dariush MansouryDepartment of Marine Physics, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Iran0000-0003-4190-4498Journal Article20220506This research presents a model for prediction of tidal currents in shallow sea areas. This hydrodynamic model is based on the solution of shallow water equations. Also contains effects of earth rotation, topographic changes, and influences of bottom friction. One of the results of solving these equations is the dispersion relation of tidal wave in the study area by which the wave number of each tidal constituent is obtainable. Finding velocity and direction of tidal currents is among other results of solving these equations. Thus, for low-amplitude waves in shallow water, the direction and velocity of tidal currents can be calculated hourly and on different days throughout the year. In order to facilitate calculations, a computer program was written in C++ programming software by which the tidal currents in the Strait of Hormuz have been computed at different times and the results have been diagrammed accordingly. This research indicates that the average velocity of tidal currents at the sea surface of the Strait of Hormuz during Spring tide is 0.35 m/s and ranges between 0.02 m/s - 1.7 m/s. The maximum tidal current velocities occur in shallow coastal waters, whereas in other areas these values are lower. As a result, the range of tidal currents in the Strait of Hormuz is more than that of the Persian Gulf. In addition, results showed that the tidal current direction upon entrance and exit in the Strait indicates the anticlockwise circulation of currents in the Persian Gulf. https://www.ijcoe.org/article_149357_17f8efadddf35c57b432879f7210fb57.pdfIranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201Numerical modelling the effect of wind on Water Level and Evaporation Rate in the Persian Gulf475314935810.22034/ijcoe.2021.149358ENOmid MahpeykarKhorramshahr University of marine science and technologyMohammad Reza KhalilabadiMalek-Ashtar University of Technology0000-0002-7000-1848Journal Article20220506Evaporation is one of the most important quantities in the marine climate, and in the Persian Gulf, this parameter makes it one of the saltiest free waters in the world. Evaporation estimation is essential for water balance studies, irrigation, and land resource planning. Persian Gulf is known as shallow water and therefore has a high temperature in summer, which increases the rate of evaporation and high salinity up to 50PPT. In this study, the effect of wind speed and direction on the rate of evaporation in the Persian Gulf, assuming that there is no water inflow into the basin, was investigated using numerical modelling. Mike model is based on the three-dimensional solution of the Navier Stokes equations, assumption of incompressibility, Boussinesq approximation, and hydrostatic pressure. The effects of wind on evaporation at four different wind speeds and four different wind directions have been investigated. Results show the wind direction has little effect on evaporation, but wind speed has significant changes on evaporation rate and water level, and these changes are nonlinearly related to water temperature so that in summer the evaporation rate increases faster with increasing temperature.https://www.ijcoe.org/article_149358_e05c7e605f93d2c9d1f85c6b8bd14430.pdfIranian Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-87316120210201Modeling of wind driven waves and estimation of wave energy in Chabahar Bay556414935910.22034/ijcoe.2021.149359ENAlireza Bahmanzadegan JahromiMarine Science Department, Science and Research Branch, Islamic Azad University of Tehran, IranMojtaba EzamMarine Science Department, Science and Research Branch, Islamic Azad University, Tehran, Iran.0000-0002-1627-5741Abbas Ali Ali Akbari BidokhtiInstitute of Geophysics, University of Tehran, Tehran0000-0003-4841-2218Kamran LariPhysical Oceanography Department, North Tehran Branch, Islamic Azad University, Tehran, IranJournal Article20220506Sea waves are one of the main characteristics of water areas in the world, which are mainly produced by wind. Waves are the main boundary condition in the dynamic loading and hydraulic calculations of coastal structures. Numerical models are being developed to bring the sea and ocean conditions closer to the real conditions. In this research, the SW model from MIKE21 software is used to simulate wind waves in the Chabahar Bay and the energy extracted from these waves is estimated. The SW model simulates the growth, transmission and decay of wind waves in offshore and coastal areas. Chabahar Bay is a semi-closed and subtropical bay with an average depth of 7.5 m, which is located in the southeast of Iran. The model was implemented for a period of one year (2017) with a spatial resolution of maximum 5 km for offshore regions and less than 500 m in the interior parts of Chabahar Bay. ECMWF model wind data with a time step of 6 hours and a spatial resolution of 0.125 minutes were used. Comparison of model results for hourly averages with measured data shows a correlation coefficient of 0.84 for significant wave height. The annually average and maximum of wave height due to wind in the entrance of Chabahar Bay is 0.82 m and 2.19 m, respectively. The direction of the dominant waves is from south and the largest share of energy is related to waves with a period of around 11. The average of annual extractable power related to wind waves in the southern parts of Chabahar Bay was calculated from the order of 3 kW/m.https://www.ijcoe.org/article_149359_a2645fa5458e144da27bbc05142615f7.pdf