MEASUREMENTS IN A LARGE-ANGLE OBLIQUE JET IMPINGEMENT FLOW

THE flowfield associated with the oblique impingement of an axisymmetric jet (see Fig. 1) is of interest as a result of its presence in numerous technological problems. Prominent among these is the externally blown flap (ebf) configuration for STOL aircraft. An extensive study of the shallow angle (0≤α≤15 deg) case has been summarized by Foss and Kleis.l The present communication is concerned with a more complicated large-angle case, viz., a = 45 deg. Prior experimental studies provide some insight into the structure of the largeangle flowfield. Donaldson and Snedecker2 investigated a wide range of Mach numbers, jet-plate spacings, angles, and impact plate dimensions via surface pressure and centerplane velocity measurements. Westley et al.3 provide surface rms pressure measurements. Fink4 has examined the acoustic characteristics of the large-angle impinging jet flows and has advanced some interpretations of the probable turbulence structure associated with them. Given the information base of these studies, and recognizing the motivation of the ebf configuration, a detailed study of the a = 45 deg, h/d = 4.95 oblique jet impingement flow was deemed to be appropriate. The Reynolds number, u0d/v, was 4.8×l04; this value is considered to be sufficiently large that qualitatively similar results are expected for larger Reynolds numbers which may be found in flows of technological interest. The jet Mach number was approximately 0.1. © 1979 American Institute of Aeronautics and Astronautics, Inc., All rights reserved.