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An Experimental Study of Supersonic Dual Coaxial Free Jet  

Baek, Seung-Cheol (Department of Mechanical Engineering, Kyungpook National University)
Kwon, Soon-Bum (Department of Mechanical Engineering, Kyungpook National University)
Lee, Byeong-Eun (Department of Aeronautical Engineering, Kyungpook National University)
Publication Information
Journal of Mechanical Science and Technology / v.17, no.12, 2003 , pp. 2107-2115 More about this Journal
Abstract
A supersonic dual coaxial jet has been employed popularly for various industrial purposes, such as gasdynamic laser, supersonic ejector, noise control and enhancement of mixing. Detailed characteristics of supersonic dual coaxial jets issuing from an inner supersonic nozzle and outer sonic nozzles with various ejection angles are experimentally investigated. Three important parameters, such as pressure ratios of the inner and outer nozzles, and outer nozzle ejection angle, are chosen for a better understanding of jet structures in the present study. The results obtained from the present experimental study show that the Mach disk diameter becomes smaller, and the Mach disk moves toward the nozzle exit, and the length of the first shock cell decreases with the pressure ratio of the outer nozzle. It was also found that the highly underexpanded outer jet produces a new oblique shock wave, which makes jet structure much more complicated. On the other hand the outer jet ejection angle affects the structure of the inner jet structure less than the pressure ratio of the outer nozzle, relatively.
Keywords
Dual Coaxial Jet; Ejection Angle; Mach Disk; Nozzle Pressure Ratio; Pitot Impact Pressure; Supersonic Flow;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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