The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures...The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures from different aspects and perspectives, we would have to evaluate many different parameters about them. So categorizing these parameters can help to perform their related analysis with more accuracy and more details. Due to the efficient force it exerts on the structure, the pressure distribution around every marine or hydraulic structure has a significant importance, and it even accounts for one of the dominant issues in designing and building of such structures. In the present study, an oil platform located in Phase 15 of South Pars oil fields, located in the Persian Gulf waters, has been analyzed using the FLOW 3D software. The outputs indicate that the pressure of water is distributed almost hydrostatically with the depth, and its maximum reaches 0.6 MPa at the bottom.展开更多
As the Armor shape has a significant effect on the reduction of wave overtopping, this study compares the performance of various shapes of concrete armored blocks of X block and Tetrapod as the most suitable armors. I...As the Armor shape has a significant effect on the reduction of wave overtopping, this study compares the performance of various shapes of concrete armored blocks of X block and Tetrapod as the most suitable armors. In this study, a three-dimensional numerical model was used for simulation of the effects of waves on the armors of Tetrapod and X Block breakwaters. In this regard, in order to calibrate the numerical model, a sample of conventional stone armor has been selected and using available experimental data on the design of armor such as wave overtopping, wave height, period of waves and energy density of the required spectral range of wave verification was conducted on a numerical model. In this regard, it is necessary to calibrate all the conditions of the model including boundary conditions, numerical modeling, initial conditions, numerical solvers and other parameters in the numerical model and simulation error rate is determined. The maximum error of the numerical model for the relative height values of the impact waves on the structure of breakwater is 7.87% for different conditions. Accordingly, the maximum error of the numerical model in determining overtopping values is 7.81%. The average fluctuation value of overtopping in the X block armor has dropped by about 31% compared to the tetrapod armor.展开更多
Compound section is referred to a section the surface of which is made of several sub-sections with different flow characteristics. The difference in the hydraulic and geometry characteristics causes a complexity in f...Compound section is referred to a section the surface of which is made of several sub-sections with different flow characteristics. The difference in the hydraulic and geometry characteristics causes a complexity in flow hydraulic and creates an interaction between the main channel and floodplains, resulting in an apparent shear stress and a transverse momentum transfer. The amount of such a stress plays an important role in many river engineering measures [1]. Due to the flow complexity, the common approximate analytical methods are not enough to identify the flow profile. The FLOW3D Software with its great features in three-dimensional analysis of flow field is used as a tool to investigate the shear stress in a direct symmetrical compound rectangular channel. After the simulation of models, it is found that an increase in the relative width and relative depth parameters decreases the percentage of apparent shear stress and an increase in the relative roughness causes it to be increased [2].展开更多
Naiband Gulf is part of Naiband National Park known as Iran’s first marine national park. It is Iran’s most important habitats in the northern Persian Gulf due to mangrove forests, coral community, and community of ...Naiband Gulf is part of Naiband National Park known as Iran’s first marine national park. It is Iran’s most important habitats in the northern Persian Gulf due to mangrove forests, coral community, and community of marine animals. The study examines the sediment transport in the Naiband Gulf and around it, where to achieve this. First, the required data including coastline information, sediment profile, and bathymetry information and waves are obtained. Then by Mike21, 2011 Version models, it was attempted to simulate waves and currents due to it in the coastal zone to determine the rate and direction of sediment transport in the Naiband Gulf area. The results obtained in this study indicate that the majority of sediment transport directions on both sides of the gulf have been internal. The existence of structures in the north and south of the Gulf has reduced alongshore sediment flows and sedimentation, especially in the south of the gulf that is a serious threat to corals.展开更多
In the present study, the Karun River in Khuzestan province in Iran is that is somehow considered the river with the most water in the country was examined. To examine the depth and speed of the flow, which undoubtedl...In the present study, the Karun River in Khuzestan province in Iran is that is somehow considered the river with the most water in the country was examined. To examine the depth and speed of the flow, which undoubtedly have the greatest impact on the environment and ecosystem of the river, two-dimensional simulation by CCHE2D model was used. In this study, it was observed that, firstly, the changes of depth and velocity along the river have good coordination and the highest changes were observed in the meander and arches. Moreover, due to using two-dimensional model, there is the possibility of examining changes of parameters in the longitudinal and transverse direction that shows the two-dimensional model is an efficient and powerful model in studying river flows.展开更多
文摘The humans’ need to use the oceans for exploration and extraction of oil has led to the development of engineering science in the field of offshore structures. Since it’s important to examine the offshore structures from different aspects and perspectives, we would have to evaluate many different parameters about them. So categorizing these parameters can help to perform their related analysis with more accuracy and more details. Due to the efficient force it exerts on the structure, the pressure distribution around every marine or hydraulic structure has a significant importance, and it even accounts for one of the dominant issues in designing and building of such structures. In the present study, an oil platform located in Phase 15 of South Pars oil fields, located in the Persian Gulf waters, has been analyzed using the FLOW 3D software. The outputs indicate that the pressure of water is distributed almost hydrostatically with the depth, and its maximum reaches 0.6 MPa at the bottom.
文摘As the Armor shape has a significant effect on the reduction of wave overtopping, this study compares the performance of various shapes of concrete armored blocks of X block and Tetrapod as the most suitable armors. In this study, a three-dimensional numerical model was used for simulation of the effects of waves on the armors of Tetrapod and X Block breakwaters. In this regard, in order to calibrate the numerical model, a sample of conventional stone armor has been selected and using available experimental data on the design of armor such as wave overtopping, wave height, period of waves and energy density of the required spectral range of wave verification was conducted on a numerical model. In this regard, it is necessary to calibrate all the conditions of the model including boundary conditions, numerical modeling, initial conditions, numerical solvers and other parameters in the numerical model and simulation error rate is determined. The maximum error of the numerical model for the relative height values of the impact waves on the structure of breakwater is 7.87% for different conditions. Accordingly, the maximum error of the numerical model in determining overtopping values is 7.81%. The average fluctuation value of overtopping in the X block armor has dropped by about 31% compared to the tetrapod armor.
文摘Compound section is referred to a section the surface of which is made of several sub-sections with different flow characteristics. The difference in the hydraulic and geometry characteristics causes a complexity in flow hydraulic and creates an interaction between the main channel and floodplains, resulting in an apparent shear stress and a transverse momentum transfer. The amount of such a stress plays an important role in many river engineering measures [1]. Due to the flow complexity, the common approximate analytical methods are not enough to identify the flow profile. The FLOW3D Software with its great features in three-dimensional analysis of flow field is used as a tool to investigate the shear stress in a direct symmetrical compound rectangular channel. After the simulation of models, it is found that an increase in the relative width and relative depth parameters decreases the percentage of apparent shear stress and an increase in the relative roughness causes it to be increased [2].
文摘Naiband Gulf is part of Naiband National Park known as Iran’s first marine national park. It is Iran’s most important habitats in the northern Persian Gulf due to mangrove forests, coral community, and community of marine animals. The study examines the sediment transport in the Naiband Gulf and around it, where to achieve this. First, the required data including coastline information, sediment profile, and bathymetry information and waves are obtained. Then by Mike21, 2011 Version models, it was attempted to simulate waves and currents due to it in the coastal zone to determine the rate and direction of sediment transport in the Naiband Gulf area. The results obtained in this study indicate that the majority of sediment transport directions on both sides of the gulf have been internal. The existence of structures in the north and south of the Gulf has reduced alongshore sediment flows and sedimentation, especially in the south of the gulf that is a serious threat to corals.
文摘In the present study, the Karun River in Khuzestan province in Iran is that is somehow considered the river with the most water in the country was examined. To examine the depth and speed of the flow, which undoubtedly have the greatest impact on the environment and ecosystem of the river, two-dimensional simulation by CCHE2D model was used. In this study, it was observed that, firstly, the changes of depth and velocity along the river have good coordination and the highest changes were observed in the meander and arches. Moreover, due to using two-dimensional model, there is the possibility of examining changes of parameters in the longitudinal and transverse direction that shows the two-dimensional model is an efficient and powerful model in studying river flows.
