Page 341 - AWSAR 2.0

Wind turbine rotor, for successful power generation and due to the design constraint, has to rotate in the certain RPM range. But wind load depends on the atmospheric conditions, and variable, so it becomes difficult to maintain the RPM in that particular range. To maintain the RPM in the specified range, a mechanism is required which changes the angle of attack according to the wind load. Whenever wind load increases, this mechanism should reduce the angle of attack of the rotor blade, and when wind load reduces the angle of attack should increase. The mechanical or electrical mechanism makes the whole system very complex. But by using the bending- twisting coupling of composite materials, this mechanism can be developed without any complexity introduction to the system. The blade will bend forward or backward, depending on the wind load, and accordingly, the blade will twist, which results in a change in the angle of the attack according to wind load.
Grumman X-29 is an unconventional,
Mr. Nishant Shakya || 317
experimental aircraft tested by NASA for US air force. This is a forward-swept wing aircraft, it provides excellent rolling control at very high speed and is extremely stable when compared to a conventional aircraft. Due to this design, wings are additionally loaded in twisting, this requires wing material of higher torsional rigiditywithoutcompromisingonthestructural load. This is achieved in these aircraft by using the bending- twisting coupling. Lift force bends the wing of the aircraft and due to the coupling blade twisted in the opposite direction to the applied twisting moment. This provides the additional torsional rigidity to the wing.
Significance of the material has been explained with help of the above examples, where, we, in particular, are focused to explore the hidden potential of the materials through inhomogeneity and anisotropy. We are developing mathematical model to analyze such anisotropic and non-homogeneous materials, which will be boon in developing the indigenous structures for aerospace, medical, and defense applications.