Optical fibre sensors for skin friction measurement

该计划将研究使用光纤核心中形成的光栅结构来测量局部静压分布和相应的机翼上的表面摩擦阻力估计。对于光纤中传播的光，该光栅结构充当了高度波长选择的反射镜，反射波长取决于诸如温度和应变等局部参数。许多传感器可以在一根光纤中制造，整个传感器阵列不受电磁干扰。光纤为传感器网络提供了可能性，这种网络就像飞机的神经系统一样，可以在多个位置检测压力、应变和温度。然后，这些信息可以反馈给驱动系统，以优化飞机的性能。特别是，我们打算探索使用光纤布拉格光栅作为压力传感器的新方法。传感器将在风洞中设计、建造和测试。这些测试将在空中客车2D、3单元高升力机翼配置上进行。后续程序可以结合光纤弯曲传感器，这样除了可以获得压力分布之外，还可以获得机翼形状。这些光纤可以在其内部的适当位置制造额外的光栅传感器，以实现结构健康监测。最后，同样的光纤也有可能用于飞机周围的光通信，因为它工作在与用于传感的波长不同的波段

The programme will investigate the use of grating structures formed in the core of an optical fibre to measure local static pressure distributions and corresponding skin friction drag estimates on a wing. The grating structure acts as a highly wavelength selective mirror for light propogating in the fibre, the relected wavelength dependent on local parameters such as temperature and strain. Many sensors can be fabricated in a single fibre and the entire sensor array is immune to electromagnetic interference. Optical fibres offer the potential for a network of sensors that act like a nervous system for an aircraft detecting pressure, strain, temperature at multiple locations. This information can then be fed back to actuatuion systems to optimise the aircraft performance. In particular we intend to explore novel methods of using fibre Bragg gratings as pressure sensors. Sensors will be designed and constructed and tested in a windtunnel. These tests will be conducted on an Airbus 2D, 3 element high lift wing configuration. Follow on programmes can incorporate fibre optic bend sensors such that the wing shape can be obtained in additon to the pressure distribution. These optical fibres can have additional grating sensors fabricated within them at suitable locations to enable structural health monitoring. Finally, the same optical fibres also have the potential to be used for optical communication around the aircraft by operating in a different wavelength band to that used for sensing