Dynamically Coupled Systems

申请人近年来的主要研究重点是开发智能直升机旋翼叶片的真实结构和动态模型，该模型可用于模拟这些叶片的动态行为，并具有很高的保真度。在该研究计划的前一阶段，开发了一个没有初始跨向扭转的智能转子叶片的连续模型。该模型将集成式压电纤维作为宏观纤维复合材料（MFC），利用压电致动器影响叶片的动态响应，研究了不良动态响应的可控性。在此研究计划前一阶段发展的基础上，下一阶段将包括以下目标：****1。研究智能宏纤维复合材料（MFC）直升机旋翼叶片控制舰载直升机桨叶航行现象（BSP）的能力和通用性。在舰船甲板上直升机旋翼桨叶启停作业中，桨叶的弹性响应关系到飞行安全和人员安全。当舰载直升机上的旋翼处于接合或分离状态时，在低速旋转时，它们会受到高风致气动力的影响，而不会在较高的正常运行速度下产生离心加强。这种激励与船舶甲板运动和风力条件相结合，有可能导致转子叶片过度变形，即所谓的BSP。因此，旋翼叶片可以接触到机身或直升机的尾臂。这种现象在造成机体严重损坏并可能使飞行器的适航性受到质疑的同时，也相当严重地危及飞行机组人员和船舶甲板人员的安全。为了降低BSP，本研究计划将开发一种主动控制策略，通过嵌入式mfc使用主动扭转来增强被动控制策略，如增加集体螺距设置。****2)该方案还将包括优化集成MFC致动器在叶片中的位置和配置，以获得最佳的致动权限。****3)现有的发展并没有考虑到在大多数（如果不是全部的话）现代直升机旋翼叶片中存在的初始扭转的影响。一个更真实的转子叶片模型需要在横截面分析中纳入这样的特征。****4)在该研究计划的前一阶段为旋翼机开发的转子叶片模型现在可以进一步开发和应用于研究水平轴风力涡轮机（HAWT）的动态行为，并预测在海上和陆地上的HAWT农场开发的功率和扭矩******

A major focus of the applicant's research program in the recent years has been the development of a realistic structural and dynamic model of a smart helicopter rotor blade that can be used to simulate dynamic behaviour of these blades with a high degree of fidelity. A continuous model of a smart rotor blade, without initial span-wise twist, was developed in the previous phase of this research program. This model that incorporates integrated piezoelectric fibres as Macro Fibre Composites (MFC) can be used to investigate the controllability of undesirable dynamic responses by using the piezoelectric actuators to influence the dynamic response of the blades. Building on the developments of the previous phase of this research program, the next phase will include the following objectives:****1. Investigate the capability and versatility of smart Macro-Fibre Composite (MFC) helicopter rotor blades to control Blade Sailing Phenomenon (BSP) in shipboard helicopters has been under investigation in my research group. During start-up and shut-down operations of helicopter rotor blades on ship decks, the elastic response of blades is of concern for flight safety and personnel reasons. While the rotors are being engaged or disengaged on a shipboard helicopter, at low speeds of rotation they can be subjected to high wind-induced aerodynamic forces without the benefit of the centrifugal stiffening present at the higher normal operating speeds. This excitation combined with ship deck motion and wind conditions has the potential of resulting in excessive deformations in rotor blades that is referred to as the BSP. As the result, the rotor blades can come into contact with the fuselage or tailboom of the helicopter. This phenomenon, while resulting in substantial levels of airframe damage with the possibility of bringing the airworthiness of the vehicle into question, also compromises the safety of flight crew and the ship deck personnel quite seriously. To reduce the BSP, this research program will develop an active control strategy using active twist through embedded MFCs to augment passive control strategies, like increasing the collective pitch setting.****2) This program will also include optimization of the placement and configuration of the integrated MFC actuators in the blade to obtain the best actuation authority.****3) The existing development does not take into account the effect of initial twist that is present in most, if not all, modern helicopter rotor blades. A more realistic modelling of rotor blades requires the incorporation of such a feature in cross-sectional analysis.****4) The rotor blade model that is developed for rotorcrafts in the previous phase of this research program can now be further developed and applied to investigate the dynamic behaviour of horizontal axis wind turbine (HAWT) and to predict the power and torque developed in HAWT farms both off-shore and land-based.******