Society Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Interaction of the breaking and non-breaking solitary waves and linear and nonlinear slopes sea bed by SPH method1723537610.22034/ijcoe.2025.512138.1152ENAminFathiAssistant Professor, Faculty of Civil Engineering, Hormozgan University, Bandar Abbas , Iran0000-0001-5634-3553CyrusErshadiHormozgan University0000-0001-9553-0386Journal Article20250321Investigating solitary waves is critical for predicting the tsunami waves features in the coastal region. The Smooth Particle Hydrodynamic method (SPH) is the Lagrangian meshless method that is commonly used to simulate nonlinear waves and free surface problems. In this study, the SPH method is used to investigate the propagation of the breaking and non-breaking solitary waves over the linear and nonlinear sharp slopes sea bed. The presented SPH model is validated in comparing the experimental and another numerical model. The results show that the presented method prepares powerful tools to simulate the solitary wave propagation over the variable sea bed. Then, the transmitted solitary wave from the linear and nonlinear sharp slopes of the sea bed were compared. The results show that the solitary wave energy loss for waves propagating through the linear slopes is more than that of non-linear slopes. Moreover, the solitary wave transmission coefficient increases with increases in wave height in the linear and nonlinear slope. Also, the transmitted solitary wave height through the nonlinear slope is slightly more than the linear slope. Finally, the breaking Solitary waves when passing through the variable depth in the near shore with nonlinear slopes is investigated by comparing the wave free surface, streamlines, and orbital velocities before and after wave breaking. The results show that the solitary wave horizontal orbital velocity values after the wave breaking are increasing in comparison with before breaking.https://www.ijcoe.org/article_235376_7f86503dfcf82b5c5dc35b4addb92fff.pdfSociety Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Vibration Control of a Composite Panel Carrying Concentrated Masses Under Different Boundary Conditions81823537710.22034/ijcoe.2025.513241.1151ENMohsenKouhiDept. of Water Resources Engineering, Faculty of Civil Engineering, University of Tabriz, Iran0000-0001-7648-6041AlirezaMojtahedi0000-0002-7917-434XMehranDadashzadehDept. of Water Resources Engineering, Faculty of Civil Engineering, University of Tabriz, Iran0000-0001-9521-7330ShabnamEbrahimiDept. of Mechanical Engineering, Sahand University of Technology, Tabriz, Iran0000-0003-3985-7653Journal Article20250321Composite panels are commonly used structural forms in marine environments, subjected to complex dynamic loads and vibration forces due to harsh operational conditions. Understanding their vibrational behavior is crucial for ensuring structural reliability and performance. The presence of localized mass variations, such as concentrated masses from attached equipment or marine growth, significantly influences their dynamic response. This study investigates the impact of concentrated masses on the vibrational characteristics of a composite panel under fixed and pinned boundary conditions through comprehensive experimental and numerical analyses. A finite element (FE) model was developed and updated based on experimental modal analysis results. The findings reveal that the location and magnitude of concentrated masses play a critical role in altering mode shapes and reducing natural frequencies. The introduction of concentrated masses leads to a systematic frequency shift, with greater reductions observed for higher mass magnitudes. The validated FE model enables an extended parametric analysis, reducing the dependency on extensive experimental testing. These insights provide a foundation for optimizing vibration control strategies in composite marine structures, contributing to improved design methodologies for enhanced structural integrity and performance.https://www.ijcoe.org/article_235377_09f5b6a5bf844d43c4d09cf6d86f5761.pdfSociety Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Numerical Investigation on Dynamics of DeepCWind Floating Offshore Wind Turbine (FOWT) Platform192723537810.22034/ijcoe.2025.499768.1129ENMohammadAhmadiMechanical Engineering Department, Babol Noshirvani University of Technology, Babol, Iran0000-0001-5653-7171MahdiYousefifardMechanical Engineering Department, Babol Noshirvani University of Technology, Babol, Iran0000-0001-5653-7171HashemNowruziMechanical Engineering Department, Babol Noshirvani University of Technology, Babol, Iran0000-0003-3773-4297Journal Article20250417Renewable energies are a crucial component of sustainable development. Offshore wind energy is an interesting clean energy alternative to fossil fuels. In floating offshore wind turbines (FOWTs), a lower floating platform couples/integrates with the upper wind turbine, and the motion of each component influences the other. Therefore, understanding the dynamic behaviors of FOWT platforms is necessary for designing them in real sea states. The present paper numerically investigates the heave and pitch dynamic motions of the DeepCWind FOWT platform at three different offsets between the columns, all under regular waves. To this accomplishment, a 3D RANS-VOF model is implemented in the open-source CFD platform of OpenFOAM. The current numerical simulations of heave and pitch motions of the sandglass-type platform with appropriate accordance are validated against the existing experimental data. The main results show that increasing the offsets between the FOWT platform columns (wide model) significantly reduces the heave and pitch motions. However, the effects of decreasing the distance between the columns (i.e., a tight model) on heave and pitch motions are insignificant compared to the original model.https://www.ijcoe.org/article_235378_5e91648fa91c47a72558f4ea4143f3b7.pdfSociety Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Characteristics of a Circular Cylinder Response under Vortex-Induced Vibration in a Subcritical Flow Regime283423537910.22034/ijcoe.2025.512732.1173ENMohammadrezaVaselaliDepartment of Nonliving Resources of Atmosphere and Ocean, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran0009-0008-8427-344XMaryamSoyuf JahromiDepartment of Nonliving Resources of Atmosphere and Ocean, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas, Iran0000-0002-7877-6277AbolfazlPourrajabianDepartment of Energy, Materials and Energy Research Center (MERC), Karaj, Iran0000-0003-0600-315XJournal Article20250518In this study, the characteristics of vortex-induced vibration (VIV) of a rigid, smooth circular cylinder elastically mounted in the water flow are investigated. The cylinder has one degree of freedom and is constrained to oscillate only in the vertical direction. The flow Reynolds number lies within the Transition of Shear Layer 3 (TrSL3) region of the subcritical flow regime. The governing equations, namely the continuity and Navier-Stokes equations, are solved using computational fluid dynamics (CFD). The finite volume method is employed for discretizing the equations, implemented through the ANSYS Fluent software. The Pressure Based solver and the PISO algorithm are utilized to couple the equations. The two-dimensional unsteady Reynolds-averaged Navier-Stokes (URANS) equations are solved using the k-ω SST turbulence model. A simplified mathematical model describes the system dynamics and fluid forces associated with the cylinder’s vortex-induced vibration. Examination of the vortices shed in the wake region reveals a P+S vortex shedding pattern. Additionally, the time history of the cylinder’s displacement ratio exhibits a sinusoidal shape, whereas the recorded lift and drag coefficient data are non-sinusoidal due to the P+S vortex shedding mode. Frequency analysis of the cylinder’s response indicates that the oscillation frequency of the cylinder matches the dominant frequency of the lift force. Furthermore, the dominant frequency of the drag force is twice that of the lift one.https://www.ijcoe.org/article_235379_1ebf207e56379722de808577a4e9d102.pdfSociety Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Numerical simulation of plate scour around offshore platforms and strategies to prevent it354523538010.22034/ijcoe.2025.489028.1112ENSeyed AmirrezaMirabotalebiDepartment of Civil Engineering, To.C., Islamic Azad University, Tonekabon, Iran.MehdiNezhadnaderiDepartment of Civil Engineering, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.0000-0003-1160-358XMehdiShamsiDepartment of Civil Engineering, To.C., Islamic Azad University, Tonekabon, Iran.RezaZahediDepartment of Civil Engineering, To.C., Islamic Azad University, Tonekabon, Iran.MohammadGholamiDepartment of Civil Engineering, To.C., Islamic Azad University, Tonekabon, Iran.TahaMehrzadDepartment of Civil Engineering, To.C., Islamic Azad University, Tonekabon, Iran.AliSheykhbahaeiPhD Candidate in Physical Oceanography at university of Hormozgan/ Iranian National Institute for Oceanography and Atomospheric science0000-0002-3476-9104MohammadrezaNazeriyanDepartment of Civil Engineering, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.Journal Article20250525With the increase in construction in the sea, protective structures are considered to prevent their instability in the marine environment. Among the coastal protective structures, submerged plates are used in marine structural engineering to prevent scour. Therefore, it is very important to study and understand the erosion and sedimentation process in the area of the offshore platform base lines in terms of design, protection and maintenance. In this research, using the computational fluid dynamics method and Fluent software, the flow around the submerged offshore platform base was simulated with different Reynolds number states. The results of the iso velocity lines, m/s, show that the speed decreases behind the offshore platform base. The maximum speed is below the offshore platform base line, which will cause scour. By increasing the Reynolds number from 3000 to 7000, the maximum speed in this state increases. The results of the iso pressure lines in Pascals show that the pressure behind the base presses and decreases above and below it. The maximum negative pressure is below the base line of the offshore platform, which will cause scouring. As the Reynolds number increases from 3000 to 7000, the negative pressure in this case increases from -0.07 to -0.3 in Pascal, which will cause scouring. The maximum pressure is below the base line of the offshore platform, which is significantly higher than the case without the use of plates, which reduces the risk of scouring around the base.https://www.ijcoe.org/article_235380_13f059b30c9412bf4278337b23941e91.pdfSociety Of Marine Science and TechnologyInternational Journal Of Coastal, Offshore And Environmental Engineering(ijcoe)2980-873110420251101Field investigation of water mass stratification and variability in the Strait of Hormuz455423538210.22034/ijcoe.2025.547481.1196ENSamadHamzeiIranian National Institute for Oceanography and Atmospheric Science0000-0002-4823-0054AmirmahdiZarbooIranian National Institute of Oceanography and Atmospheric Sciences0009-0001-0544-1417EmadKoochaknejadIranian National Institute for Oceanography and Atmospheric Science0000-0002-6751-1847Journal Article20250918The Persian Gulf is a shallow basin characterized by high evaporation rates, resulting in the formation of one of the saltiest water bodies in the world. To compensate for the evaporative water loss, a less saline water mass enters the Gulf through the Strait of Hormuz, known as the Indian Ocean Surface Water (IOSW). Due to its high density, the hypersaline Persian Gulf Water (PGW) sinks toward the seabed and exits the Gulf through the deeper layers of the Strait of Hormuz, flowing toward the Gulf of Oman. To identify and characterize the water masses present in the Persian Gulf, Strait of Hormuz, and Gulf of Oman, hydrographic surveys were conducted during the summer and winter seasons of the 2102 and 2201 expeditions aboard the Persian Gulf Explorer. Using CTD profiling, physical and chemical parameters of seawater were measured. Analysis of temperature, salinity, and potential density anomaly across isopycnal layers—surface, intermediate, and deep—along north-south and east-west vertical transects enabled the evaluation of water mass structure and distribution in the region. Results indicate that during summer, surface water mixing is intense due to atmospheric conditions such as the monsoon, and stratification primarily occurs below depths of 30 meters. In contrast, winter stratification weakens, and due to lower temperatures, horizontal layering is observed from the eastern Strait of Hormuz to the western end of the Persian Gulf—marked by increasing salinity and density, and decreasing temperature. The IOSW enters the Persian Gulf through the Strait of Hormuz and propagates along the northern coastline. In summer, cyclonic eddies in the Gulf induce southward flow in several central regions. The PGW is observed in the deep central Gulf during summer, while surface mixing between IOSW and Gulf waters reduces salinity in the upper layers. The summer PGW mass is detectable in the western Gulf of Oman at approximately 100 meters depth near the Strait of Hormuz. However, in winter, the inflow into the Gulf weakens due to reduced wind forcing and strong horizontal stratification of salinity and density, which limits the penetration of incoming water.https://www.ijcoe.org/article_235382_ec89d3d24702aa69f837de742baf3a42.pdf