Flowfield Measurements About an Airfoil with Leading-Edge Ice Shapes
Andy P. Broeren, and Michael B. Bragg
University of Illinois, Urbana, Illinois, 61801
and
Harold E. Addy Jr.
NASA John H. Glenn Research Center at Lewis Field, Cleveland, Ohio 44135
ABSTRACT
Flowfield measurements were carried out on the upper surface of a GLC-305 airfoil configured with glaze and rime ice-shape simulations. The mean and root-mean-square fluctuation of the streamwise velocity were measured
using a split-hot-film probe at several chordwise locations. These data were taken at three different angles of
attack preceding stall for each iced-airfoil configuration at Reynolds numbers of 3.5 × 106 and 6.0 × 106 with
Mach numbers of 0.12 and 0.21. The velocity measurements confirmed the presence of a large separation bubble
downstream of the ice shapes. The separation bubbles for the glaze ice configuration were much larger than those
for the rime ice case, resulting from the differences in the ice horn geometry. Other than the differences in size, the
integral boundary-layer characteristics were very similar. Changes in Reynolds number did not significantly affect
the separation bubble characteristics. However, a larger Mach number did result in a slightly larger separation
bubble for the glaze ice case at a = 6 deg. The root-mean-square velocity distributions had peak values in the
separated shear layer, downstream of transition, that compared well with previous work.