| A new dynamic resonant wall shear stress sensor based on an oscillating sensor element operating near its resonant frequency has been investigated both numerically and experimentally. The experimental results of this study showed that, with a change in the mean shear stress acting on the sensor surface, measurable sensor sensitivity in the oscillation amplitude occurs for both open loop and closed loop control of the sensor. This is definitive experimental evidence that a resonant system can be made sensitive to wall shear stress and it is suggested that the concept of a dynamic resonant wall shear stress sensor would work. Furthermore, these results agree qualitatively with numerical results in boundary layer flow and provide a rigorous basis upon which further development of the dynamic resonant sensor can be pursued. At the same time, the sensor's working principle was numerically investigated and sensor parameters effects (oscillating amplitude, oscillating frequency; and sensor size), pressure gradient effects were also numerical estimated. In the end three dimensional effects that include aspect ratio effects, inflow angle effects and gap effects were also discussed by building three-dimensional dynamic models in Fluent. |
