Effects of Embedded Vortices on Heat Transfer in a Turbulent Boundary Layer withFilm Cooling from Holes with Compound Angles

摘要

The effects of embedded longitudinal vortices on film cooling injectant from onerow and two rows of holes with compound angles are investigated. Holes are designed such that their angle from the test surface is 30 degrees in a spanwise/normal plane projection, and 35 degrees in a streamwise/normal plane projection. A blowing ratio of 0.5, non-dimensional injection temperature parameters of 1.29 to 1.38, and freestream velocity of 10 m/s are employed. As the spanwise position of the vortex is altered. Stanton Numbers change considerably depending upon which portion of each vortex is proximate to film injection holes. These variations are vastly different depending on whether or nor spanwise components of vortex secondary flows are opposed or aligned with the spanwise direction of the injectant. Mean velocity surveys, injection distribution surveys, and flow visualization results are also discussed.