Heat transfer distributions on a cylinder with simulated thermal barrier coating spallation Academic Article uri icon


  • Detailed heat transfer distributions are presented over a turbine blade leading-edge model with simulated thermal barrier coating spallation. The blade leading-edge region is simulated by a cylinder in a crossflow with a tailboard. The heat transfer measurements are presented only on one side of the front half of the cylinder. The simulated spallation cavities are rectangular in shape and have rounded corners. The effect of a spallation cavity is studied at four different locations (0-20, 10-30, 20-40, and 35-55 deg). Two different cavity depths are studied at each location to understand the effect of spallation depth on local heat transfer distributions. The effect of freestream turbulence on detailed heat transfer is also presented for each case. Detailed heat transfer measurements are obtained using a transient liquid crystal technique. Detailed heat transfer distributions present the local high-heat transfer and low-heat transfer regions inside and outside the spallation. Results show that spallations can enhance heat transfer up to two times compared with that for a smooth surface. Results also show that the spallation location and depth have a strong effect on local heat transfer distributions on the leading edge. An increase in freestream turbulence further increases the heat transfer coefficients caused by the spallation. 1998 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

published proceedings


author list (cited authors)

  • Ekkad, S. V., & Han, J. C.

citation count

  • 6

complete list of authors

  • Ekkad, SV||Han, JC

publication date

  • January 1999