جستجوی مقالات مرتبط با کلیدواژه « کاهش ارتعاشات صفحه ای » در نشریات گروه « فنی و مهندسی »

In this paper, the vibration reduction of a small-scale horizontal axis wind turbine blade is investigated using the shunt damping method by considering the coupling between edgewise and flapwise vibrations. First, the nonlinear differential equations governing the blade dynamics with shunt damper are derived using the Lagrange method. Then, by performing the sensitivity analysis and selecting the appropriate cost function and constraints, the shunt damper parameters are optimized using the genetic algorithm method for a real blade. It should be noted that in this study, the wind force applied to the blade is considered sinusoidal with variable frequency at four different speeds. After solving the governing dynamic equations, to evaluate the effectiveness of the mentioned method in reducing vibrations, the obtained results in this study are compared with the corresponding results of employing the optimized tuned mass damper for suppression of edgewise vibrations of the blade. Results show that the tuned mass damper and shunt damping method have good effects on reducing vibrations. Despite that, the tuned mass damper effect on vibration reduction at high wind speeds is greater than the shunt damping method, at low wind speeds, the shunt damping has a greater effect on reducing vibrations.

Vibration in wind turbine blades is one of the important factors that result in reducing performance of wind turbines. Therefore, control or reduction of the mentioned vibrations can be of great help in increasing efficiency of wind turbines. In this paper, an optimal tuned mass damper (TMD) is proposed to reduce edgewise vibration of an small-scale horizontal axis wind turbine blade (5 KW) with considering the coupling between edgewise and flapwise vibrations. For this purpose, partial differential equations governing dynamics of the system are derived using the Lagrange method. These equations are completely nonlinear and linearization is not performed to avoid possible errors in the analysis and also, the blade is considered as a flexible member. In deriving governing equations, coupling effect between in-plane and out-of-plane vibrations of the blade, effect of pre-twist angle in the coupling, and effect of centrifugal forces and gravity are considered. In order to reduce vibration of the blade, TMD is used and its parameters are optimized using one of the genetic algorithm methods for a real blade sample. Finally, with applying wind force as a sweep sine excitation, effectiveness of the optimized TMD in vibration reduction of the blade in four different wind speeds is investigated and the related results are presented. Results show that the wind turbine blade vibration reduction is achieved properly using the optimal TMD.