**1.1. Benefits of wind energy**

In [1], scientists and researchers have tried to accelerate solutions for wind energy genera‐ tion design parameters. Researchers claim that a short time, society, industry, and politics will welcome the use of wind energy as a clean, practical, economical, and environmentally friendly alternative. In an effort to approach a more sustainable world, after the 1973 oil cri‐ sis RE sources began to appear on the agenda, and wind energy attracted significant inter‐ est. Because of extensive studies on this topic, wind energy has recently been applied in various industries, where it has begun to compete with other energy resources [1].

Among the various renewable energy types as highlighted by [2], wind provides an inter‐ mittent but environmentally friendly energy source that does not pollute atmosphere. Wind power calculations are initiated from the kinetic energy definition, and wind power is found to be proportional to half the air density multiplied by the cube of the wind velocity. When seeking to determine the potential usage of wind energy, wind power formulation is de‐ rived first by use of kinetic energy definition and then by basic physical definitions of power as the ratio of work over time, work as the force multiplied by the distance, and force as the change of momentum. [2].

© 2012 Huleihil and Mazor; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2012 Huleihil and Mazor; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

## **1.2. Aerodynamics aspects of wind turbines**

Reviews about many of the most important aerodynamic research topics in the field of wind energy are shown in the report of a different study [3] Wind turbine aerodynamics concerns the modeling and prediction of aerodynamic forces, such as performance predictions of wind farms, as well as the design of specific parts of wind turbines, such as rotor-blade ge‐ ometry. The basics of blade-element momentum theory were presented along with guide‐ lines for the construction of airfoil data. Various theories for aerodynamically optimum rotors were discussed, and recent results on classical models were presented. State-of-the-art advanced numerical simulation tools for wind turbine rotors and wakes were reviewed, in‐ cluding rotor predictions as well as models for simulating wind turbine wakes and flows in wind farms [3].
