Anupam Sharma从他的爱荷华州立大学办公桌上方的书架上拉出了手风琴夹。里面是小心收集的短猫头鹰的翅膀。
他说，这里可能是开发超级飞机和风力涡轮机的一些线索。
爱荷华州立航空航天工程助理教授夏尔马说：“猫头鹰几乎在飞行中几乎完全保持沉默。”GE。“猫头鹰不仅在滑行飞行中保持沉默，而且在拍打飞行中，这真是太神奇了。”
然后，夏尔马（Sharma）捡起了翅膀（爱荷华州禽生态学家斯蒂芬·丁斯莫尔（Stephen Dinsmore）收集的标本），并指出了三部分的“猫头鹰赫什套件”，负责无声飞行。
First, at the leading edge of the wing there are small, fine, comb-like structures. Second, all the feathers at the trailing edge of the wing end in a pliable and porous fringe. And third, there’s a downy coat on the flight feathers.
To learn exactly how that hush kit manipulates air flow, turbulence and pressure to produce silent flight, Sharma is scanning owl wing specimens, creating digital models and running multi-day simulations that use more than 16,000 processers provided by one of the country’s top-ranked supercomputing facilities at Argonne National Laboratory in Illinois. He and his colleagues hope their studies will produce practical ideas for making ultraquiet aircraft and wind turbines.
以前有关于猫头鹰翅膀和无声飞行的研究。美国军方还研究了猫头鹰的飞行，以寻求隐形飞机的想法。
But, Sharma said few have taken a high-powered computational approach to the studies.
夏尔马说：“我们可以详细介绍您无法学习实验。”
夏尔马（Sharma）在今年早些时候在丹佛（Denver）举行的一些数字调查在美国航空和宇航学研究所的航空声学会议上进行了报道。Sharma还描述了猫头鹰翅膀的毛衣外套如何激发他在弗吉尼亚理工大学的合作者设计模型机翼（飞机机翼的弯曲形状），并带有一系列的一系列小型，薄的“ Finlets”和檐篷，并在刀片和尾部边缘附近平行于气流。弗吉尼亚理工大学航空航天与海洋工程学教授，大学稳定风洞主任威廉·德文波特（William Devenport）领导了弗吉尼亚州的实验。
两个研究团队都将猫头鹰启发的机翼的性能与标准的扁平表面机翼进行了比较。
Sharma said the computer simulations showed the owl-inspired airfoils substantially reduced the unsteady pressure on the back end of the blade surface. And, the researchers found that the sound radiated by the owl-inspired design was reduced by up to 5 decibels over a wide frequency range. This noise reduction was observed without sacrificing aerodynamic performance.
Sharma said the experiments performed by the Virginia Tech researchers agreed with the simulations. The researchers found the owl-inspired designs reduced noise and they also demonstrated that fence spacing on the airfoil is an important design parameter.
美国国家科学基金会（National Science Foundation）正在以五年，500,000美元的职业赠款（该基金会最负盛名的早期职业教师奖）为夏尔马（Sharma）的研究提供支持。爱荷华州太空赠款联盟还通过100,000美元的赠款支持了这项研究。国家科学基金会和Argonne领导力计算设施正在为研究计算机时间提供支持。
In addition to Sharma, the grants are supporting the research of three Iowa State students in aerospace engineering: Andrew Bodling and Bharat Agrawal, doctoral students; and Vishal Vijay, a master’s student.
夏尔马（Sharma）团队的2016年论文并发表在《国际航空声学杂志》上，该杂志指出，受猫头鹰翅膀启发的锯齿状前缘测试，发现锯齿大大减少了机翼噪音。该论文还建立了导致降噪的物理机制。
将猫头鹰的静套套件应用于机翼和风力涡轮机叶片的所有模拟，测试和数据并不意味着下一代飞机或风力涡轮机将看起来像猫头鹰的机翼。
夏尔马说：“我们的方法是生物启发的，而不是生物模仿。”“我们的设计看起来不像猫头鹰的翅膀。我们正在研究猫头鹰无声飞行背后的物理机制。然后，我们采用受猫头鹰翅膀启发的简化几何形状，并将其应用于飞机翅膀，喷气发动机和风力涡轮机的转子叶片。”
Sharma使用3D打印来快速开发模型来测试各种想法和几何形状。
So far, the studies are telling him the owl has potential to help engineers develop ultraquiet flight and wind energy, although applications might start at smaller scales and low speeds, such as drones or unmanned aerial vehicles.
After that, Sharma wrote in a project summary, “The results of this research could have an impact on the design of silent air vehicles with application in national defense, in commerce and in transportation.”
提交以下：Aerospace + defense
