M. Ghodsi Hasanabad
Volume 2, Issue 2 , June 2012, Pages 135-140
Abstract
In this study, boundary element method was used to model sea wave propagation on a hemisphere shape under water tank and oil-water common surface oscillation in the tank. Also, kinematic and dynamic oundary conditions of free surface and common surface of oil and water were discritized by Finite ...
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In this study, boundary element method was used to model sea wave propagation on a hemisphere shape under water tank and oil-water common surface oscillation in the tank. Also, kinematic and dynamic oundary conditions of free surface and common surface of oil and water were discritized by Finite difference method. There were some singularities in BEM method, which were removed by applying zoning method. The wave specifications and water depths, which were entered in numerical model, were extracted from Geographic and climatic profiles of Abuzar oil field region in Persian Gulf. The results show an acceptable accordance with ther researches. Also, the results illustrated that, using open ended storage tanks near our offshore platforms has not any problem and it can be a good proposal for oil storing by considering their advantages.
A. H. Javid; M. Abbaspour; S. A. Mirbagheri; H. JanfeshanAraghi
Volume 2, Issue 2 , June 2012, Pages 141-148
Abstract
The study of wave and its propagation on the water surface is among significant phenomena in designing quay, marine and water structures. Therefore, in order to design structures which are exposed to direct wave forces, it is necessary to study and simulate water surface height and the wave ...
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The study of wave and its propagation on the water surface is among significant phenomena in designing quay, marine and water structures. Therefore, in order to design structures which are exposed to direct wave forces, it is necessary to study and simulate water surface height and the wave forces on the structures body in different boundary conditions. In this study, the propagation of static sinusoidal wave in deep water environment with complex boundary conditions are simulated by using Smoothed Particle Hydrodynamics (SPH) technique. The governing equations are programmed using VISUAL FORTRAN6.5 and the solution results are visualized using TECPLOT. After determining the suitable number of particles for simulation, the duration of sinusoidal wave oscillation are measured by simulation and are compared with analytical solution. After ensuring the accuracy and veracity of proposed SPH method in simulation of static sinusoidal wave motion on the deep water surface, the simulation are carried out in more complex boundary conditions which there are no analytical solutions.
Sh. Sharafatmandjoor; F. Sabetghadam; H. R. Fathalizadeh; A. Shahirpour
Volume 2, Issue 2 , June 2012, Pages 149-152
Abstract
In this study, we proposed a novel scheme for the implementation of the no-slip boundary condition in thelattice Boltzmann method (LBM) . In detail , we have substituted the classical bounce-back idea by the direct immersed boundary specification . In this way we construct the equilibrium density ...
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In this study, we proposed a novel scheme for the implementation of the no-slip boundary condition in thelattice Boltzmann method (LBM) . In detail , we have substituted the classical bounce-back idea by the direct immersed boundary specification . In this way we construct the equilibrium density functions in such a way that it feels the no-slip boundaries . Therefore , in fact a kind of equilibrium boundary condition is made . Results show that the proposed method presents also a faster solution procedure in comparison to the bounce-back scheme .
M. R. Tabeshpour; R. Shoghi
Volume 2, Issue 2 , June 2012, Pages 153-162
Abstract
Tension-Leg Platform (TLP) is a vertically moored floating structure. The platform is permanently mooredby tendons. Surge equation of motion of TLP is highly nonlinear because of large displacement and it should be solved with perturbation parameter in time domain. This paper compare the dynamic ...
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Tension-Leg Platform (TLP) is a vertically moored floating structure. The platform is permanently mooredby tendons. Surge equation of motion of TLP is highly nonlinear because of large displacement and it should be solved with perturbation parameter in time domain. This paper compare the dynamic motion responses of a TLP in regular sea waves obtained by applying three method in time domain using MATLAB soft ware. In this paper Lindstedt- Poincare method (L-P method) is used to solve nonlinear differential equation of surge motion considering first-order perturbation. Also modified Euler method (MEM) is used for solving nonlinear equation of motion as numerical method and ordinary differential equation is used for linear equation of motion (without nonlinear term). The results were obtained as responses represent good accordancebetween results of L-P method and MEM.
F. S. Sharifi; M. Ezam; A. Karami Khaniki
Volume 2, Issue 2 , June 2012, Pages 163-170
Abstract
In this study, the capabilities of WAWEWATCH-III and MIKE21-SW for predicting the characteristics ofwind-generated waves in Hormuz Strait are evaluated. The numerical models have been set up using Input data including GFS wind with 5° spatial resolution and 6 hours time intervals, along with ...
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In this study, the capabilities of WAWEWATCH-III and MIKE21-SW for predicting the characteristics ofwind-generated waves in Hormuz Strait are evaluated. The numerical models have been set up using Input data including GFS wind with 5° spatial resolution and 6 hours time intervals, along with the ETOPO1 bathymetry data with 2 arc-minute spatial resolutions. The results of the two model simulations were compared with the available satellite altimetry measurements of significant wave heights at the modeling area. The comparisons show that in deep water WAVEWATCH-III results in more reliable prediction of wave characteristics in comparison to the MIKE-21 SW. While in shallow area the MIKE-21 gives more consistencies with altimetry measurements. These may be due to the benefits of the unstructured grid which are used in MIKE-21, lead to better representations of the coastal area. The investigation on the direction of wind generated waves in the modeling area show that in some regions despite of the increase in wind speed, significant wave height remains nearly unchanged. This is mainly because of rapid changes in wind direction over the Strait of Hormuz.
A. Mashinchian Moradi; A. H. Dashti; M. R. Fatemi; P. Aberoumand Azar
Volume 2, Issue 2 , June 2012, Pages 171-176
Abstract
Tracking and determining the amount and types of urban sewage that is being releasing to the environment is important in planning for wastewater treatment systems and water quality control. In this research, in four stations of Anzali Lagoon, (by means of a gas chromatograph device with mass ...
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Tracking and determining the amount and types of urban sewage that is being releasing to the environment is important in planning for wastewater treatment systems and water quality control. In this research, in four stations of Anzali Lagoon, (by means of a gas chromatograph device with mass detector spectrometer) wastewater pollution has been measured and evaluated with molecular indicator Linear Alkyl Benzene(LABs) in bivalve “Anodonta cygnea”. Average concentrations of LABs were calculated 520 μg/kg dry weight in samples of station 1, 1245 in station 2, 2144 in station 3, and 1746 in station 4. Results from this study indicate severe LABs pollution in studied stations in Anzali Lagoon’s sugesing that urban wastewater has reached these stations.