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The dynamic inflow model in yaw condition was constructed based on the theory of BEM revised model and Pitt-Peter model; besides first-order differential equation of dynamic inflow model was also figured out by using fourth-order Runge-Kutta method. When taking large deformation of flexible blade during the working proceed and the feedback of flexible structural deformation on dynamic inflow model into consideration, the gradient mechanisms of induce factor on wind turbine were obtained in different circumstances, such as in the wind shear, wind turbulence, yaw, transition of rotor speed and blade pitch angel. Dynamic induce factor of one 5MW wind turbine was figured out, dynamic description of induce factor was founded, what's more dynamic inflow model and analytical method suitable for flexible blade were established, all these calculate were achieved by employing MATLAB programming. The validity and practicality of dynamic inflow model with flexible structural feedback were confirmed by comparing the calculate results of different models. [ABSTRACT FROM AUTHOR]

In order to study the influence of the vibration and deformation of the blade on the aerodynamic damping of the horizontal axis wind turbine, the aerodynamic force is calculated using the BEM theory, and the dynamic response is calculated using finite element method, and then the aerodynamic damping model is built based on the energy loss method. The influence of flap-wise, edge-wise and twist deformation on the angle of attack is mainly studied. The influence of the flap-wise velocity and edge-wise velocity on inflow angle and inflow velocity is also taken into consideration. As an example, the aerodynamic damping of a 5 MW offshore baseline wind turbine rotor is calculated. The results indicate that the angle of twist and the flapwise deformations have great influence on the aerodynamic damping in flap-wise direction. It may reduce the aerodynamic damping in flap-wise direction, but the edge-wise deformation only affect the aerodynamic damping in edge-wise direction. The deformation has no influence on aerodynamic damping distribution alone the blade. [ABSTRACT FROM AUTHOR]

In order to improve multilevel isotonic mixed ejector's performance, all kind parameters of multilevel isotonic mixed ejector's were matched and optimized. Perfect ejector compress ratio and efficiency were acquired. This paper analyzes the one level isotonic mixed ejector by experiment, indicated the effects of one level isotonic mixed ejector's parameters change, and then, make certain the multilevel isotonic mixed ejector's level principle, match and optimize multilevel isotonic mixed ejector's all kinds of parameters. As a result, if the ejecting Mach number, the ejected temperature, one level isotonic mixed ejector's ejecting coefficient and compress ratio are matched and optimized, multilevel isotonic mixed ejector's performance will be improved evidently. [ABSTRACT FROM AUTHOR]