한국소음진동공학회:학술대회논문집 (Proceedings of the Korean Society for Noise and Vibration Engineering Conference)
- 한국소음진동공학회 1997년도 추계학술대회논문집; 한국과학기술회관; 6 Nov. 1997
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- Pages.256-262
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- 1997
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- 1598-2548(pISSN)
고속 원형충돌제트의 불안정 특성
Instabilities of High-speed Impinging Circular Jets
초록
The characteristics of the unstable impinging circular jet were investigated based on the frequency characteristics and the sound field of the impinging-tones. Two symmetric modes Si and S2, associated with low frequency and high frequency respectively, and one helical mode H have been observed by measuring frequency and phase-distribution around the jet. Radiation characteristics of impinging-tone were studied by measuring axial directivity. It was founded that the radiation patterns of symmetric and helical mode are different and it is toward the plate as the impinging distance increased. By estimating the convection velocity of the unstable jet, it was founded that the convection speed decreases with the frequency and its decreasing pattern varies with unstable modes S1, S2 and H, respectively.
키워드