A wind turbine is a device that converts kinetic energy from the wind, also called wind energy , into mechanical energy ; a process known as wind power . If the mechanical energy is used to produce electricity, the device may be called wind turbine or wind power plant. If the mechanical energy is used to drive machinery, such as for grinding grain or pumping water, the device is called a windmill or wind pump . Similarly, it may be called wind charger when it is used to charge batteries. The result of over a millennium of windmill development and modern engineering, today's wind turbines are manufactured in a wide range of vertical and horizontal axis types. The smallest turbines are used for applications such as battery charging or auxiliary power on boats; while large grid-connected arrays of turbines are becoming an increasingly important source of wind power -produced commercial electricity. The aim of this study is to numerically simulate the Magneous wind turbines with the rotational circular cylinders. At first , the fluid flow over stationary and rotational circular cylinders are assessed using some other numerical and experimental results. From the results of this study , it is observed that by using steady - state assumption the results from the most of turbulence models has failed due to unsteady behaviour of the actual flow and defficiency of turbulence models to predict separated flows. Therefor , the transient flow solver with the BSL turbulence model have used with proven better result in agreement with some experimental data. By varying the rotational velocity of the circular cylinders , as means of the turbine impeller , from 300 rpm to 8000 rpm , the power coefficient are obtained versus the wind turbine tip-speed ratio , and also with the power curve of some other conventional wind turbine. Some correlation is used to relate the rotor rotational velocity to the cylinder rotational speed. from the simulation results , the benefit of using Magneous wind turbine is assessed in comparison with other conventional wind turbine. The thesis comprise five chapters. In the first chapter , the litreture of Magneous type wind turbines are reviewed. In the second chapter , the physical concept of Magneous effect in ideal flows are discussed. In the third chapter , the governing Viscous fluid flow equations are given and the various turbulence models used in this study are explored.In chapter four , the geometry of the problem are introduced and the simulation results are discussed. In the final chapter of 5 , the conclusion of this work and suggestion for future work is given. Key words : Wind turbine, rotational cylinder, Magneous force, numerical simulation.