Interactions between embedded vortices and injectant from film cooling holes with compound angle orientations in a turbulent boundary layer

Conference · Sat Jan 01 04:00:00 EST 1994 · Journal of Turbomachinery; (United States)

OSTI ID:5068281

Ligrani, P M ^[1]; Mitchell, S W ^[2]

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1. Univ. of Utah, Salt Lake City, UT (United States). Dept. of Mechanical Engineering
2. Naval Postgraduate School, Monterey, CA (United States). Dept. of Mechanical Engineering

Experimental results are presented that describe the effects of embedded, longitudinal vortices on heat transfer and film injectant downstream of two staggered rows of film cooling holes with compound angle orientations. Holes are oriented so that their angles with respect to the test surface are 30 deg in a spanwise/normal plan projection, and 35 deg in a streamwise/normal projection. A blowing ratio of 0.5, nondimensional injection temperature parameter [theta] of about 1.5, and free-stream velocity of 10 m/s are employed. Injection hole diameter is 0.945 cm to give a ratio of vortex core diameter to hole diameter of 1.6--1.67 just downstream of the injection holes (x/d = 10.2). At the same location, vortex circulation magnitudes range from 0.15 m[sup 2]/s to 0.18 m[sup 2]/s. By changing the sign of the angle of attack of the half-delta wings used to generate the vortices, vortices are produced that rotate either clockwise or counterclockwise when viewed looking downstream in spanwise/normal planes. The most important conclusion is that local heat transfer and injectant distributions are strongly affected by the longitudinal embedded vortices, including their directions of rotation and their spanwise positions with respect to film injection holes. Differences resulting from vortex rotation are due to secondary flow vectors, especially beneath vortex cores, which are in different directions with respect to the spanwise velocity components of injectant after it exits the holes. Surveys of streamwise mean velocity, secondary flow vectors, total pressure, and streamwise mean vorticity are also presented that further substantiate these findings.

• OSTI ID: 5068281
• Report Number(s): CONF-920602--
• Conference Information: Journal Name: Journal of Turbomachinery; (United States) Journal Volume: 116:1
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200104* -- Fossil-Fueled Power Plants-- Components
COOLING
EFFICIENCY
ENGINES
FILM COOLING
GAS TURBINE ENGINES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
TURBINE BLADES
VORTICES