A master thesis was discussed in Department of Mechanical Engineering / College of Engineering at University of Mosul entitled “Modeling and simulation of the performance of wind turbines under Iraqi weathers conditions” submitted by (Raja Jarallah Abdul Rahman), Supervised By Dr. Ahmed Khalid Ibrahim on Thursday, March 03, 2022.In the last few years, the world has witnessed a large demand for using clean renewable energy sources in order to reduce enviromental pollution, energy cost and fuel consumption. Wind energy. is one of the Sources of energy that people have used since ancient times. so wind has become an important, source of energy in all over the world, because it does not cause Pollution to the enviroment, as in fossil fuels, which is one of the problems of the modern era. Therefore, this work focuses on an important sector in renewable energy, which is wind energy, where it is necessary to develop improvement, of wind turbine performance through turbine simulation strategies to reduce the cost of Power which generation which is highly desirable by the wind industry.This study focuses on the design of diffuser – Powered wind turbines with the three states of the turbine who are Nozzle, shroud and Diffuser, one of these innovations is the wind turbine (DAWT). DAWTS work to increase the Power of the turbine and thus increase its efficiency by is increasing the wind speed, by using a diffuser, wind turbine i in addition to changing the blade angle. The Simulation is carried out by using ANSYS Fluent software to simulate and predict fluid flow velocity. There is need for computational fluid dynamics (CFD) to improve the design of the turbines, as the stimulation result is a reference that can be used to expand the knowledge of the dynamic behavior of the turbines and improve their performance in the future. The wind speed data is also collected at a height of 50 meters for five selected sites in Iraq to determine wind speed distribution.The sites include Mosul and parts of it, Nasiriyah, Baghdad and Basra, at an altitude of 50 meters. During the collection of recorded data, the potential of wind energy in Iraq states that the site of Basra and Nasiriyah enjoys good wind speed that reached more than 6 meters Per second, where these can be invested by establishing projects of wind energy investment.