Resource for wind tunnel tests of smart helicopter rotorblade system

由于旋翼机产生的高水平的外部噪音和振动，直升机不能被更广泛地使用。直升机产生的噪声和振动主要来源于主旋翼的非定常空气动力学。低频振动主要是由后退叶片的动态失速产生的，而高频噪声主要是在机动和下降飞行状态下，当动叶与前叶尖端产生的涡流相互作用时产生的。旋翼飞机领域的最新研究重点是开发综合主动控制系统，以更有效地控制旋翼叶片产生的噪声和振动。在过去，由于缺乏能够承受直升机旋翼环境特征载荷的执行器，这些系统无法开发。在实现高效控制的新解决方案中，那些涉及固态致动器（“智能”）或自适应结构的解决方案最有前途。最近在欧洲和美国进行的实验表明，噪音和振动只能同时略微减少，尽管有报告称两者都有显著减少。2005年6月，一家主要制造商首次成功试飞了带有主动旋翼叶片系统的旋翼。由NSERC和MMO资助的卡尔顿大学设法吸引了另一个主要欧洲制造商的注意，并将有机会在2007年在意大利的风洞试验中展示一个独特的概念，该概念是由内部开发的“智能”直升机叶片系统，其目标是同时衰减噪音和振动。所要求的设备（一套6个特殊的大电流放大器）将允许在计划的风洞测试中充分验证这一新颖的、完全加拿大的概念，并保持工业合作伙伴的支持，目标是在未来几年内进行全面的飞行测试。

Helicopters cannot be used more extensively due to the high levels of exterior noise and vibration generated by rotorcraft. The most important components of noise and vibration produced in helicopters are originated in the main rotor from the unsteady aerodynamics. Low-frequency vibration is mostly generated by dynamic stall in the retreating blades, whereas high-frequency acoustic noise is produced mainly in manoeuvring and descent flight regimes when the rotor blades interact with the vortices shed by the tips of the preceding blades. The state-of-the-art research in the area of rotorcraft is focused in developing integrated active control systems to perform more efficient control of noise and vibration produced by rotorblades. In the past, these systems could not be developed due to the lack of actuators able to withstand the loads that characterize the helicopter rotor environment. Among the new solutions to achieve efficient control, those that involve solid-state actuators - the "smart" - or adaptive structures are the most promising. Recent experiments performed in Europe and the United States indicated that both noise and vibration could only be reduced marginally at the same time, although significant reductions of each individually were reported. One of the major manufacturers has successfully flown for the first time a rotor with an active rotorblade system in June 2005. Carleton University funded by NSERC and MMO managed to attract the attention of another major European manufacturer and will have the opportunity in 2007 to demonstrate in wind tunnel tests in Italy a unique concept developed in-house for a "smart" helicopter blade system with the objective of attenuating noise and vibration simultaneously for the first time. The requested equipment (a set of six special high-current amplifiers) will allow the full validation of this novel and totally Canadian concept in the planned wind tunnel tests and keep the support of the industrial partner, aiming at full-scale flight tests within the next few years.