• Ms. Lauren Hunt
  • Texas A&M University
  • Holden Auditorium
  • 4:00 p.m.

Laminar Flow Control (LFC) techniques are used in air-vehicle design to delay the onset of boundary-layer transition, ultimately reducing fuel burn and improving aircraft efficiency. Delaying transition on a swept wing dominated by a
crossflow instability through the use of spanwise-periodic discrete roughness elements (DRE) has been successfully demonstrated both in ground and flight tests. However, the DRE effectiveness appears much more limited under flight conditions. The reason for the difference between wind tunnel and flight tests is not well understood, but a recently reactivated ground test capability may begin to explain these differences.

The low-disturbance Klebanoff-Saric Wind Tunnel was relocated from Arizona State University (ASU) to Texas A&M University (TAMU) in 2005. During its subsequent reconstruction, several component modifications were introduced to further enhance flow quality and experimental control. This talk discusses the changes made to the tunnel and the resulting flow-quality measurements. Final turbulence levels are compared to the ASU flow quality and the significance of these results is discussed in the context of an on-going crossflow instability experiment at TAMU using the ASU model. New stability and receptivity data and their implications for ongoing flight and wind tunnel tests are presented.

Acknowledgement: This work was supported by the NASA Aeronautics Scholarship Program and AFOSR Grant FA9550-08-1-0093.