توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Free–Surface Hydrodynamic Analysis of Floating Offshore Structures (FOS)Using Multiphase Flow Modeling
اطلاعات انتشار: هفتمین همایش بین المللی سواحل، بنادر و سازه های دریایی، سال
تعداد صفحات: ۵
Floating Offshore Structures like platforms or buoys subjected to cyclic loads caused by wind, waves and currents. The motion of FOS and the resultant loads can be predicted with increased accuracy using new CFD techniques. Although studies of the deformed free surface near the waterline have been already performed, CFD studies of FOS separate the aerodynamic and hydrodynamic phenomena. While the separation of aero– and hydrodynamics saves time for modeling and simulation, it does not take into account the strong interaction between the forces associated with each. Moreover the role of viscous effects on the free surface elevation is often neglected, and this prevents such things as water flow separation from being properly captured.
The aim of this study is to couple CFD analysis of the aerodynamic flow around the masts, together with the hydrodynamic flow around the hull and mooring line of a cylindrical buoy, including viscous effects and surface wave generation at the waterline. The volume of fluid (VOF) model in FLUENT software was used for this purpose. This multiphase model is designed for immiscible fluids (air and water in this case), and tracks the interfaces between them. The environmental conditions were adopted based on the met–ocean data of the Persian Gulf.
The results of particular interest from the analysis include the free surface elevation with the related wave drag, and the aerodynamic and hydrodynamic lift and drag acting on the masts, hull, and mooring line. The lift and drag results can be used to derive the thrust and lateral forces on the buoy, which can then be used to predict the buoy velocity corresponding to a fixed configuration in terms of heave, drift and heel angles.<\div>

۲Stability of flow between two eccentric cylinders With heat transfer and rotation
نویسنده(ها): ،
اطلاعات انتشار: یازدهمین کنفرانس دینامیک شاره ها، سال
تعداد صفحات: ۱۲
The effect of a radial temperature gradient on stability of steady–state flow of a viscous liquid between two solid eccentric cylinders with inner one rotate in determined velocity was investigated. The existence of hydrodynamic instabilities leads to formation of Taylor vortices in flows in the annulus between two cylinders. The study of heat transfer within the rotating enclosure is complex. For horizontal configuration, the buoyancy and the centrifugal effects (created by the heated rotating cylinder) give rise to fully three–dimensional flows. Understanding the dynamics of these flows is of great practical interest because they are encountered in many engineering and geophysical problems, and it may help to improve mass and heat transfer involved in different processes, e.g. cooling of rotating electrical machinery and turbines rotors or to explain some dynamical processes in the oceans and the atmosphere. The linear stability problem is considered in the Boussinesq approximation and the results of 3D numerical analysis of flow and heat transfer in two horizontal eccentric cylinders with a heated rotating inner cylinder are presented. Solutions are presented for a number of Taylor and Reyleigh numbers.<\div>

۳Parametric study on the stability of a liquid jet using VOF method
اطلاعات انتشار: هشتمین همایش انجمن هوافضای ایران، سال
تعداد صفحات: ۶
The object of the study is to investigate the behavior of liquid jet which is discharged in to air. This problem has great importance in aerospace engineering especially in lubrication of the airplane engines such as bearing box lubrication. The main adventage of this study is consideration of the second phase of the flow which is air in this study. The problem is numerically simulated by using volume of fluid (VOF) method which is based on conservation of each fluid in the domain. Surface tension effect is also considered by including surface tension as a volumetric force in Navier–stokes equations. Because our numerical simulation is unsteady, Navier–Stokes equation is solved by explicit projection method. Both Navier–Stokes equation and interface tracking equation are solved in each time step. The simulation is performed for different inlet velocities, also the effect of jet diameter is studied. Critical velocities are found for different inlet diameters which beyond these values the effect of gravity is negligible. Also it is found that by reducing the diameter of the liquid jet this critical velocity also reduced respectively. In order to verify the code used for the numerical simulation, dam break problem is simulated and numerical results are compared with available experimental data. Comparison of the numerical results with available experimental data reveals the accuracy of the method.<\div>

۴Statistical analysis of wind energy in Markazi Province Case Study: Saveh Station
اطلاعات انتشار: اولین کنفرانس بین المللی رویکردهای نوین در نگهداشت انرژی، سال
تعداد صفحات: ۱۰
Wind potential for clear energy production in most of Iran regions is very high. In this paper a statistical analysis on wind data of Saveh station in Markazi province is implemented. Renewable energy organization of Iran’s 12–monthed data are used for wind energy calculations. Wind velocity at 40, 30 and 10 meter height is studied firstly. Mean wind velocity on this section at mentioned height is 4.6, 4.47, 4.06 m\s respectively. Also windrose of wind blow direction is investigated. Using windrose graph, wind velocity and direction at 30 and 37.5 meters height is presented. Dominant wind direction is between north and north east. According to Saveh station wind rose dominant wind direction is fixed. It's important in turbines arrangement, because wind direction fixing is an important advantage for a wind power–station. Annual wind mean power at 10, 30 and 40 meters height show that maximum of wind power production is on MAY. Also with evaluation the annual wind average power at heights of 10, 30 and 40 meters can be seen 40 and 30 meters heights for installing wind turbines are suitable.<\div>

۵Theoretical Aerodynamic analysis of six airfoils for use on small wind turbines
نویسنده(ها): ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی رویکردهای نوین در نگهداشت انرژی، سال
تعداد صفحات: ۹
In this paper theoretical analysis of six airfoils, the AG24, AG35, AG455ct, CAL1215j, CAL2263m and CAL4041l has been done. The analysis performed in this study are intended to provide theoretical predictions for power coefficient by used of MATLAB software based on experimental measurements at low Reynolds number. The results show that the airfoil appropriate to the design is AG35Airfoil.<\div>

۶Assessing the wind energy potential locations in province of Qazvin in Iran
اطلاعات انتشار: اولین کنفرانس بین المللی رویکردهای نوین در نگهداشت انرژی، سال
تعداد صفحات: ۱۰
In this study, the ten minutes period measured wind speed data for years 2009–2010 at 10 m, 30 m and 40 m heights for one of the provinces of Iran, Qazvin have been statistically analyzed to determine the potential of wind power generation. This paper presents the wind energy potential at three stations in the province Papoli, Jarandagh and Nikoei. Extrapolation of the 10 m data, using the Power Law, has been used to determine the wind data at heights of 30 m and 40 m. From the primary evaluation and determining mean wind speed and also weibull distribution, it is found that Jarandagh has better potential for using wind energy in the province. Also with evaluation the annual wind average power for Jarandagh station at heights of 10, 30 and 40 meters can be seen 40 and 30 meters heights for installing wind turbines are suitable. The objective is to evaluate the most important characteristic of wind energy in the studied site. The statistical attitudes permit us to estimate the mean wind speed and the wind rose in the site at the height of 10m, 30 m and 40 m.<\div>

۷Feasibility of installing wind turbine to generate electricity power in Iran, Case Study: the Khuzestan province
نویسنده(ها): ، ،
اطلاعات انتشار: اولین کنفرانس بین المللی رویکردهای نوین در نگهداشت انرژی، سال
تعداد صفحات: ۱۰
In this study, the ten minutes period measured wind speed data for years 2009–2010 at 10m, 30m and 40m heights for one of the provinces of Iran, Khuzestan, have been statistically analyzed to determine the potential of wind power generation. This paper presents the wind energy potential at five stations in the province, Izeh, Abadan, Shooshtar, Hosseinieh and Mahshahr. From the primary evaluation and determining mean wind speed and also weibull distribution, it is found that Abadan has better potential for using wind energy in the province. Also with evaluation the annual wind average power for Abadan station at heights of 10, 30 and 40 meters can be seen 40 and 30 meters heights for installing wind turbines are suitable. The objective is to evaluate the most important characteristic of wind energy in the studied site. The statistical attitudes permit us to estimate the mean wind speed, the mean wind power density and the wind rose in the site at the height of 10m, 30m and 40m.<\div>

۸Investigating wind potential for clean energy production in Khorasan Razavi Province, Case Study: Jangal station
اطلاعات انتشار: نخستین همایش ملی انرژی باد و خورشید، سال
تعداد صفحات: ۹
Wind potential for clear energy production in most of Iran regions is very high. In this paper a statistical analysis on wind data of Jangal station in Khorasan Razavi province is implemented. Renewable energy organization of Iran’s 12–monthed data are used for wind energy calculations. Wind velocity at 40, 30 and 10 meter heights is studied firstly. Mean wind velocity on this section at mentioned height is 4.78, 4.52, 3.76 m\s respectively. Also windrose of wind blow direction is investigated. Using windrose graph, wind velocity and direction at 30 and 37.5 meters height is presented. Dominant wind direction is between north and northwest for 30m height and is between west and northwest for 37.5m height. According to Jangal station wind rose dominant wind direction is fixed. It's important in turbines arrangement, because wind direction fixing is an important advantage for a wind power station. Annual wind mean power at 10, 30 and 40 meters height show that maximum of wind power production is on February. Also with evaluation the annual wind average power at heights of 10, 30 and 40 meters can be seen 40 and 30 meters heights for installing wind turbines are suitable.<\div>

۹Innovative Design of New Generation of Horizontal Axis Wind Turbines (HAWT)
نویسنده(ها):
اطلاعات انتشار: نخستین کنفرانس انرژی بادی ایران، سال
تعداد صفحات: ۶
design of HAWT is introduced here.Aerodynamic design of horizontal axis wind turbines is presently obtained using the combined momentum and blade element theory(BEM). Further improvements were achieved by incorporating wake rotation, tip losses, and some off–design amendments. In all of these, noclosed analytical solutions exist, drag coefficient is always taken to be zero when calculating axial and angular induction factors,and some cumbersome iterative numerical methods are employed to obtain wind turbine parameters. The iterative methods usuallyexhibit poor convergence and also sometimeslead to non–unique multiple solutions. In our new analytical approach, the mentioned theories are advanced into a new level of closedform unique solution in which all the effects of drag coefficient, wake rotation, and tip losses are incorporated for the design of newgeneration of HAWT. It is observed from this study that the classical optimum Glauert type wind turbines are not necessarily the best initialdesign; because some modification to the near root of HAWT blades introduced in our modelling can substantially enhancecharacteristics and performance of HAWTs particularly at high wind speeds<\div>

۱۰Thermal Radiative Properties of v Nanoscale Semiconductors with vv Incoherent Formulation
اطلاعات انتشار: International Journal of Advanced Design and Manufacturing Technology، سال
تعداد صفحات: ۸

۱۱VALIDATION OF SHORT–TIME WAVE FORECASTING IN PERSIANGULF, OMAN SEA, AND PART OF INDIAN OCEAN BY USING IRANIANNUMERICAL WAVE PREDICTION MODEL
اطلاعات انتشار: یازدهمین همایش بین المللی سواحل، بنادر و سازه های دریایی، سال
تعداد صفحات: ۴
In order to predict wind–wave and swell a great number of different models have been developedwhich are based on experimental, semi experimental or theoretical models.<\div>

۱۲LOCATION OPTIMIZATION OF MEASUREMENT STATION IN THEVICINITY OF MOCRAN BEACHES BY USING HINDCAST MODEL
اطلاعات انتشار: یازدهمین همایش بین المللی سواحل، بنادر و سازه های دریایی، سال
تعداد صفحات: ۵
In order to control dangerous condition and being ready for them we need to be informed aboutthe sea condition and monitor their situation. This can be done by using buoy<\div>

۱۳Data Assimilation of Significant Wave Height in IUT Wave Forecasting Modelusing Optimal Interpolation
اطلاعات انتشار: یازدهمین همایش بین المللی سواحل، بنادر و سازه های دریایی، سال
تعداد صفحات: ۴
Studying wave and ocean has an important role in the world today. Thanks to the numerical waveprediction models and applying them in the world scale with acceptable accuracy, we can findworthy information about the sea state in the following hours.<\div>

۱۴Design of Chamber and Wells Turbine for an Oscillating Column of Water for Extracting Wave Energy from Anzali Port
نویسنده(ها): ،
اطلاعات انتشار: چهاردهمین همایش صنایع دریایی، سال
تعداد صفحات: ۵
Renewable energies such as wave energy, despite rapid technological progress and potentials in Iranian waters, are yet require careful studies. Recent developments of marine energy in the world can manifest itself for energy demands in Iran. In this paper, the procedure for design of Well’s turbine and Oscillating Water Column (OWC) containers are explained. Experimental wave measurements from Anzali port is used to design the system of OWC. Optimum sizes of the OWC container and Well’s turbine are derived for using the maximum accessible wave energy in Anzali port<\div>

۱۵Evaluation of Wave Energy Potentials in Chahbahar port using two methods of water–wind model and wave measurements
نویسنده(ها): ،
اطلاعات انتشار: چهاردهمین همایش صنایع دریایی، سال
تعداد صفحات: ۸
Renewable energies such as wave energy, despite rapid technological progress and potentials in Iranian waters, are yet require careful feasibility studies. Recent developments of marine energy in the world can manifest itself for implementing marine energy absorber devices in Iran. In this paper, the average annual wave power of Chabahar port is determined using two approaches. A wave–wind model and three months experimental data are used forcomparison. The wave–wind model predicts the annual wave power 4.746 kW\m2 (approximate method) and 8.621 kW\m2 (accurate method), which are higher than the measurements. This suggests that further improvements in modeling and more measurements should be obtained for correct evaluation of Iranian marine energy.<\div>

۱۶An Innovative Wind Propulsion System for Naval Ships
اطلاعات انتشار: پانزدهمین همایش صنایع دریایی، سال
تعداد صفحات: ۴
The Magnus effect was successfully employed by Flettner in his ship operating with two large propelling cylinders. The spinning cylinders produced propulsive force from the wind on seas which is clean and free source of energy. The rise of fossil fuel costs and extinction of fossil fuel resources have caused a renew interest in Flettner type propulsion. Thisis becoming a hot topic in naval engineering. Many other applications of producing high lift values from spinningsymmetrical cylinders have failed due to rapid increase of frictional torques and also high values of drag force. In this paper, the new application of aerofoil Magnus, wind driven propulsion system is introduced which can be effectively used for any size ships. To show validity of the concept, the NACA0020 aerofoil section with circulating skin is computationally investigated at air speed of 4 m\s correspond to the Reynolds number of 8.2104. The viscous fluidflow solutions were obtained at variety of treadmill speed of the aerofoil skin and different incident angles. The results confirm that high lift to drag ratios may be obtained using treadmill motion<\div>

۱۷Performance assessment of a hybrid fuel cell and micro gas turbine power system
اطلاعات انتشار: Energy Equipment and Systems، اول،شماره۱، Summer and Autumn ۲۰۱۳، سال
تعداد صفحات: ۱۶
In this paper, a hybrid solid oxide fuel cell (SOFC) and micro gas turbine (MGT) power system is parametrically studied to evaluate the effect of different operating conditions. The SOFC\MGT power system includes SOFC reactor, combustion chamber, compressor and turbine units, and two heat exchangers. The effects of fuel utilization, temperature, and pressure are assessed on performance of the hybrid SOFC\MGT power system using energy and exergy analyses. This study reveals that the main exergy loss occurs in the external reformer and the maximum achievable output power is about 7kW for the hybrid system. Finally, the promising first law thermal efficiency of up to 83% is achieved when the second law efficiency enhances to 65% for the hybrid system.
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