To reduce the uncertainty nature of tidal stream turbines connected to the bulk power system, energy storage systems with high capacity should be used. Among different energy storage systems, vanadium redox flow batteries with large capacity can be used in power systems. In this paper, an economic analysis is performed, and the impact of vanadium redox batteries on the power system containing tidal turbines considering reliability effect is evaluated. For this purpose, a multi-state reliability model is developed for tidal-stream turbines connected to battery units. The multi-state reliability model is used to study the adequacy of the power systems containing tidal turbines in conjunction with vanadium redox batteries. In the proposed reliability model, the failure rate of the composed components and variation in the generated power arisen from variation in tidal current speed are taken into account. Fuzzy c-means clustering technique and Xie-Beni index are utilized to determine an optimal number of clusters and probability of them in the reliability model of the system including tidal stream turbines and vanadium redox batteries. Numerical results of Roy-Billinton and IEEE reliability test systems are evaluated to study the effect of tidal stream turbines and vanadium redox batteries on the reliability of power systems and verify the effectiveness of the proposed model.

Tides continuously change the water level in seas, and due to the continuity and dominance of currents caused by tides in bays, straits and estuaries, it is necessary to investigate the phenomena related to sediment transport and scouring in the surroundings of the structures located in the above areas will be illuminated more than before. In this research, by numerical simulation of the flow field and sediment transport, the scouring phenomenon under the pipelines caused by bidirectional currents has been investigated, and according to the values ​​of movement threshold speed, depth and number of tidal cycles to reach equilibrium, the characteristics of the scouring profile has been drawn. The obtained results indicate an increase in the depth and surface of the scour pit caused by the tidal current due to the alternating changes in the flow direction compared to the scour caused by the unidirectional current, and the vortex shedding process affects the final shape of the scour profile.

In this paper, the movement of an oil spill around the Khark Island has been studied, using the hydrographic information of the Persian Gulf region and the Mike21 software. To obtain the water flow flux, a model with an irregular triangular network containing 11325 nodes was assumed and the tidal level of Hengam Island in the Strait of Hormuz and the land boundary condition on the coast were considered. Then the tidal currents in the Khark region were simulated by considering 3 open boundaries and one land boundary (the Bushehr coast). In order to calibrate the information, the tidal level in Khark station was compared with the output of the model tidal level. Based on the results of the model, the amount of water level fluctuations caused by the tides from February 15-25, 2011 were calculated to be in the range of 0.33 to 2.27 meters and the speed of the tidal currents were calculated from 0 to 0.7 meters per second. Also, the amount of water level fluctuations caused by the tides from 10 to 20 August 2011 were 0.36 to 2.19 meters and the speed of tidal currents were 0 to 0.6 meters per second. Based on the value of current obtained from the model for a station, the tidal current time series was plotted and its time-space equation was obtained. To obtain the path taken by the oil spill, the time for the spill to reach full emulsion and thus stop, is obtained using Adios2 software. In 2011 the tidal currents obtained in February were faster than August and as a result, in February 2011, there were a lot of fluctuations in the movement of the oil spill.

A numerical-analytical modeling technique was presented for predicting instantaneous energy absorption with axial tidal turbines in unsteady water flow. The goal of present paper is introducing a fast and stable integral solution approach with unique solution. This technique employs steady-state CFD data to approximate transient performance of axial tidal turbine in unsteady external flows. This solution technique was designed for modeling axial tidal turbine with convergent-divergent duct in water flow with unsteady boundary conditions. The governing equations for fluid flow were derived in the form of integral equations. The equation of one-degree of freedom motion for rotor was solved with fourth-order Runge-Kutta method and variation of parameters approach. CFD data for rotor and duct of axial tidal turbine were inserted as boundary values in integral equations of fluid flow. Two transient analytical equations were employed for approximating rotor torque and back pressure coefficient of tidal turbine. The results of integral solution approach were compared with transient CFD data in ANSYS-Fluent software. Many numerical simulations were performed to determine duct dimensions for maximum power enhancement in an axial tidal turbine.

The transient flow patterns in the Gheshm canal is due to tidal fluctuations in two open boundaries of the canal. Due to Variations of water level in the Hormoz strait and the Persian Gulf, there are considerable differences in tidal behavior of two ends of the canal. In this investigation, applications of Nasir software for solving tidal flow patterns with moving boundaries in Gheshm canal is introduced. This software computes water level variation and velocity components in horizontal plane by solving depth averaged from of continuity and momentum equations using cell vertex finite volume method for unstructured triangular mesh. For damping out of numerical oscillations of explicit solution procedure, an artificial viscosity formulation suitable for the triangular unstructured meshes was applied. A wetting and drying model is applied in present work using edge-base algorithm. The results of computer modeling have been compared with data measurements in the domain and demonstrated high performance of the model to simulate tidal currents in Gheshm canal.

Awareness of marine parameters is one of the main requirements for maritime missions, and in particular, sea currents are of particular importance. In the Persian Gulf which is considered a shallow water zone, this is among the priorities of environmental recognition. The origin of Gulf currents is mainly density, wind and tide. In the meantime, tide is of particular importance due to the prevailing factor in the creation of momentary flows of numerical hydrodynamic models, hydrography, sediment transport, and others. Since in many navigation and maritime affairs, port management and coastal engineering activities, marine currents are especially important for short-term tidal currents. This paper explores the tidal and sea currents In the Persian Gulf. The results indicate that the main factor in the tidal currents of the Persian Gulf is the moon. The tide type also follows a different pattern in different parts of the Persian Gulf, which is usually half a day in the northern half, but daily in the southern half.

Using tidal potential, the effect of tide on the gravity field, crustal deformation due to tidal force, and gravity variations resulted from the crustal deformation are presented. Tidal potential is divided into constant and periodic (diurnal and semi-diurnal) constituents, and for each constituents crustal displacements in radial, South-North, and East-West directions are computed. The aforementioned computations, which algorithmically can be summarized as follows, are implemented in a software with the capability of computing the tidal potential and the resulting crustal deformation at any time and location: (i) Using right ascension coordinates (?,? ) of the Moon and Sun, and time, zenith angle of the celestial bodies is computed as a function of time and location on the surface of the Earth. (ii) Constant and periodic constituents of the tidal potential are computed for the given points on Earth surface at the given times. (iii) Crustal displacements caused by the tidal force in the radial, South-North, and East-West directions are computed. (iv) The computed tidal potential constituents and the related tidal displacements are presented in both graphical and tabular formats. As the case study, using the aforementioned software, tidal potential and tidal deformation of the crust at geographical region of Iran is computed. Among the practical applications of this study and the developed software followings are outstanding: (i) Removal of the crustal deformation due to tide from the Global Navigation Satellite System (GNSS) observations. (ii) Removal of direct tidal effect from gravity observations. (iii) Removal of the indirect tidal gravity effect due to crustal deformation from the gravity observations. (iv) Removal of the direct tidal effect from the geoid. (v) Removal of indirect effect due to crustal deformation from the geoid. (vi) Removal of the tidal effects from the height systems.

The current and sediment transport patterns are important factors affecting coastline morphology. Subsequently، these factors are influenced by waves and currents. Currents are generated by waves breaking on the coastal area. A simultaneous presence of a long shore and tidal currents makes the inlet. A complex hydrodynamic area. The effects of tidal currents on sediment transport pattern and sedimentary features of inlets were studied by numerical modeling. The junction of a small bay to an open sea was modeled using the MIKE21 software. Different conditions of tide amplitudes (0. 5، 1. 5، 2. 5 meters) were investigated. The results clearly indicated the formation of two vortexes during transformation from flow to ebb tide and vice versa. These vortexes، in association with the tidal flow and ebb currents، produce some shallow areas at the sides of the inlet. The radius of the tidal vortexes، and the width of sedimentation area، are directly dependent on the tide amplitude. Using an analysis of Keulegan، when tide amplitudes were 1. 5 and 2. 5 meters، there was flow dominance in sediment transport capability (i. e. net bay-ward transport). when the tide amplitude was 0. 5 meter، there was the ebb dominance of sediment transport capability.

Nowadays, energy extraction from sea waves as a renewable energy source has been increasingly considered. In addition, the growing demand for energy as a result of development of industrial activities, air pollution caused by the use of fossil fuels and greenhouse problems caused a new challenge for humankind. Tidal energy is a type of energy that is derived from converting the tidal power of the sea into electricity or other types of energy applications. Although this energy is still not widely used, it has the potential to generate sustainable electricity in the future. Due to weak tidal currents, Iran has a little potential for extracting the energy to produce electricity. However, the conditions of the length and width of the Persian Gulf, and the existence of several small and large bays and their splits in the north of the Gulf, cause a special attention to this energy in recent years. In this study, a single pond system was modeled by Flow 3D software to evaluate the amount of electricity power production from the tidal wave in Bandar Abbas, Shahid Rajaee port. The results showed that a tidal wave with an average wave amplitude of 3 meters in the port could produce an average of 1267 kWh in a tidal cycle. The comparison of power production in Imam Khomeini and Shahid Rajaee ports showed that Imam Khomeini port was able to produce more power (around 65%) in comparison with Shahid Rajaee port due to its higher wave amplitude.

In this paper a mathematical model is developed to investigate the effects of tidal river fluctuations on the groundwater head of confined aquifer. To simulate the interaction between groundwater flow of the confined aquifer near tidal river in unsteady flow, we used separation method. This model is for simulating groundwater level and it requires estimation of hydrogeological parameters of transmissivity and storage coefficient. Two things falling and rising water levels have been studied in this paper. To verify the analytical solution of the model used GMS software Modflow and the results of the survey conducted comparing the effectiveness of analytical and numerical model solved by separation of variables and methods proposed model for the hydraulic confined aquifer and river tidal showed. Compared with an analytical solution based on a sinusoidal assumption and a numerical solution generated by MODFLOW, this solution provided better performance in groundwater-level prediction in a confined aquifer According to the investigation done if the coefficient of transmissibility increases water level rises. Evaluations of analytical solutions show that the effect of changes in levels of transmission capability between 1 and 2 km from the border tidal was remarkable. And with increased transmission capability, head of the underground water level rises also away from the border reduced and it create wave whit lesser amplitude and need more time to create it.