Flow Development Over An SD7003 Airfoil At Different Accelerations From Rest
Christian J. Kähler, Wolfgang Dierl, Rainer Hain
University of the Bundeswehr Munich, Neubiberg, Germany
DOI:
This work examines the effect of acceleration on the formation of a laminar separation bubble (LSB). The experiments were performed in a water towing tank with an SD7003 airfoil model accelerated from rest to a constant chord Reynolds number. Quantitative flow field measurements were performed using two-component time-resolved Particle Image Velocimetry (PIV) over a range of accelerations. A detailed analysis of the spatio-temporal flow development is conducted focusing on the LSB formation and dynamics. The results provide insight into the mechanism of LSB formation. The associated transient flow development is shown to persist over several convective time units after steady state free-stream velocity is reached, with no significant effect of acceleration on the overall transient duration. However, the acceleration rate has a substantial effect on flow development during the acceleration phase.