The aerodynamically coupled flap-pitch equations of motion of a single blade have been derived in a rotating frame as function of the azimuth angle W, When W = Wt, the equations represent the motion of the tth blade. To derive the equations of motion of all the blades as a single unit, the coefficients in […]

The dynamics of compressor stall has been re-parameterized in a form that would facilitate the construction of a non-linear control law for the active non-linear control of compressor stall. The regions of stable performance in parameter space Root Locus Fig. 5.11 Root locus plot illustrating the effect of the negative feedback of D/c (y = […]

The capacity, Q, of a cell is the approximate amount of charge that can be stored in the cell when it is fully charged. Thus, the capacity is the amount of electric charge that a battery can store, which is stated in units of ampere-hour (A-h). The state of charge (SOC) is defined as the […]

Problems of structural dynamics and aeroelasticity of wind turbine rotors are relatively well understood. Major progress in the field of wind turbine rotor dynamics was achieved during last three decades of the twentieth century thanks to improvements in performance of modern computers and application of nonlinear elastic model-based analysis to both helicopter and wind turbine […]

Electronic controllers for jet engines were developed in the 1980s. Currently, the jet engine controllers use highly customized computers to synthesize the control laws with a number of sensor inputs and actuator outputs. Such electronic con­trollers result in higher engine operating efficiencies by allowing for precise engine control through the use of multiple control loops […]

A solar cell is a device that converts light from the sun directly into electricity. They are also called photovoltaic devices. There are a wide variety of solar cells available in the market, and they are all differentiated by their different materials and structures. All of these have one target which is to produce maximum […]

4.1 Introduction Wind power has evolved rapidly in the last two decades with regard to both power rating and size of wind turbines that are currently being installed. In the past few years, several developments have taken place. There has not only been a contin­uous increase in the rated power of wind turbines being installed, […]

Compressor surge and rotating stall vibrations place fundamental limitations on aircraft engine performance and remain persistent problems in the development of axial compressor and fan stages. Compressor surge and rotating stall are purelyfluid mechanic instabilities, while blade flutter, stall flutter, and surge flutter and their variants are aeroelastic instabilities involving both blade vibrations and fluid […]