Film Effectiveness Over a Flat Surface With Air and CO2 Injection Through Compound Angle Holes Using a Transient Liquid Crystal Image Method Conference Paper uri icon


  • This paper presents detailed film effectiveness distributions over a flat surface with one row of injection holes inclined streamwise at 35 for three blowing ratios (M=0.5, 1.0, 2.0). Three compound angles of 0, 45, and 90 with air (D.R.=0.98) and CO2 (D.R.=1.46) as coolants are tested at an elevated free-stream turbulence condition (Tu8.5%). A transient liquid crystal technique is used to measure local heat transfer coefficients and film effectiveness. Detailed film effectiveness results are presented near and around film injection holes. Compound angle injection provides higher film effectiveness than simple angle injection for both coolants. Higher density injectant produces higher effectiveness for simple injection. However, lower density coolant produces higher effectiveness for a large compound angle of 90. The detailed film effectiveness obtained using the transient liquid crystal technique, particularly in the near hole region, provided a better understanding of the film cooling process in gas turbine components.

name of conference

  • ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition

published proceedings

  • Volume 4: Heat Transfer; Electric Power; Industrial and Cogeneration

author list (cited authors)

  • Ekkad, S. V., Zapata, D., & Han, J.

citation count

  • 6

complete list of authors

  • Ekkad, Srinath V||Zapata, Dyrk||Han, Je-Chin

publication date

  • June 1995