On the basic of passive damping control, we do modeling and simulating in another approach to improve the vibration alleviating effect, the piezoelectric layer damping (PLD), which is called active control. The piez...On the basic of passive damping control, we do modeling and simulating in another approach to improve the vibration alleviating effect, the piezoelectric layer damping (PLD), which is called active control. The piezoelectric damping patches are under control of PID controller (matlab simulating) in voltage defference. Here, we use the software PRO/ENGINEER to design and model a wind turbine blade before using COMSOL to simulate the dynamic motion of the wind turbine blade and its interaction with aerodynamic force of wind in finite element method. Some different models are built-- the original turbine blade and the turbine blade with damping patches on different location and quantity. Then, according to the simulation results, we compare the effects of passive and active damping control, also the effect of patches locations and quantities under different wind speed. This research can provide a direction for future study about ways to decrease vibration of turbine blades.展开更多
Within the linear framework,the Modal Electromechanical Coupling Factor(MEMCF)is an important indicator to quantify the dynamic conversion of mechanical energy and electrical energy of piezoelectric structures.It is a...Within the linear framework,the Modal Electromechanical Coupling Factor(MEMCF)is an important indicator to quantify the dynamic conversion of mechanical energy and electrical energy of piezoelectric structures.It is also an important tool to guide the piezoelectric damping design of linear structures.Advanced aircraft often fly in maneuvers,and the variable working conditions induce drastic changes in the load level on structures.Geometric and contact nonlinearities of thin-walled structures and joint structures are often activated.To achieve a good vibration reduction effect covering all working conditions,one cannot directly use linear electromechanical coupling theory to instruct the piezoelectric damping design for nonlinear structures.Therefore,this paper defines the Nonlinear Modal Electromechanical Coupling Factor(NMEMCF)and proposes the corresponding numerical method for the first time to quantitatively evaluate the electromechanical coupling capability of nonlinear piezoelectric structures.Three candidate definitions of the NMEMCF are given,including two frequency definitions and one energy definition.The energy definition is the most promising one.It is not only applicable to both conservative and dissipative nonlinear structures but also compatible with the linear MEMCF.In addition,based on the energy formula,the NMEMCF can be obtained by only performing one nonlinear modal analysis in the open-circuit state.The analytical findings and the numerical tool are validated against two piezoelectric structures with different types of nonlinearities.A strong correlation among the NMEMCF,geometric parameters,and energy dissipation is observed.The results confirm that the proposed NMEMCF captures the physics of the electromechanical coupling phenomenon associated with nonlinear piezoelectric structures and can be used as an essential design indicator of piezoelectric damping,especially for variable working conditions.展开更多
文摘On the basic of passive damping control, we do modeling and simulating in another approach to improve the vibration alleviating effect, the piezoelectric layer damping (PLD), which is called active control. The piezoelectric damping patches are under control of PID controller (matlab simulating) in voltage defference. Here, we use the software PRO/ENGINEER to design and model a wind turbine blade before using COMSOL to simulate the dynamic motion of the wind turbine blade and its interaction with aerodynamic force of wind in finite element method. Some different models are built-- the original turbine blade and the turbine blade with damping patches on different location and quantity. Then, according to the simulation results, we compare the effects of passive and active damping control, also the effect of patches locations and quantities under different wind speed. This research can provide a direction for future study about ways to decrease vibration of turbine blades.
基金funded by Major Projects of Aero-Engines and Gas Turbines(J2019-Ⅳ-0023-0091 and J2019-Ⅳ-0005-0073)Aeronautical Science Foundation of China(2019ZB051002)+1 种基金China Postdoctoral Science Foundation(2021M700326)Advanced Jet Propulsion Creativity Center(Projects HKCX2020-02-013,HKCX2020-02-016 and HKCX2022-01009)。
文摘Within the linear framework,the Modal Electromechanical Coupling Factor(MEMCF)is an important indicator to quantify the dynamic conversion of mechanical energy and electrical energy of piezoelectric structures.It is also an important tool to guide the piezoelectric damping design of linear structures.Advanced aircraft often fly in maneuvers,and the variable working conditions induce drastic changes in the load level on structures.Geometric and contact nonlinearities of thin-walled structures and joint structures are often activated.To achieve a good vibration reduction effect covering all working conditions,one cannot directly use linear electromechanical coupling theory to instruct the piezoelectric damping design for nonlinear structures.Therefore,this paper defines the Nonlinear Modal Electromechanical Coupling Factor(NMEMCF)and proposes the corresponding numerical method for the first time to quantitatively evaluate the electromechanical coupling capability of nonlinear piezoelectric structures.Three candidate definitions of the NMEMCF are given,including two frequency definitions and one energy definition.The energy definition is the most promising one.It is not only applicable to both conservative and dissipative nonlinear structures but also compatible with the linear MEMCF.In addition,based on the energy formula,the NMEMCF can be obtained by only performing one nonlinear modal analysis in the open-circuit state.The analytical findings and the numerical tool are validated against two piezoelectric structures with different types of nonlinearities.A strong correlation among the NMEMCF,geometric parameters,and energy dissipation is observed.The results confirm that the proposed NMEMCF captures the physics of the electromechanical coupling phenomenon associated with nonlinear piezoelectric structures and can be used as an essential design indicator of piezoelectric damping,especially for variable working conditions.