Open AccessEffect of Hydraulic Diameter on Potential Core Decay of Supersonic Jets
Author(s) -
Prasanta Kumar Mohanta,
B. T. N. Sridhar
Publication year - 2020
Publication title -
incas buletin
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.282
H-Index - 10
eISSN - 2247-4528
pISSN - 2066-8201
DOI - 10.13111/2066-8201.2020.12.1.11
Subject(s) - supersonic speed , nozzle , jet (fluid) , mechanics , core (optical fiber) , choked flow , hydraulic diameter , physics , geometry , optics , materials science , mathematics , turbulence , thermodynamics , reynolds number
Various studies dealing with decay characteristics of circular and noncircular supersonic jets were conducted by previous researchers. But in these studies due emphasis was not given to the hydraulic diameter (Dh), shape factor (ζ) & the nozzle lip parameters which have significant impact on the characteristics of noncircular supersonic jet. In this study, it has been shown that these parameters played a significant role on supersonic core decay characteristics [2, 3, 6] of the jet. The scope of this study included supersonic core length (Lc), decay pattern, due to noncircular shaped nozzle. In the literature, the supersonic jet characterization and the related experimental correlation are available for optimum expansion conditions whereas for other expansion (under and over) conditions the experimental correlation is barely available. While investigating experimentally, new empirical relations were obtained which were the improved forms of earlier correlations for supersonic core length [4]. For experiments, six different types of nozzles (circular, hexagon, square, triangular, elliptical and rectangular) with the same exit to throat area ratio, convergent length and divergent length were used. The results obtained from the experimentally developed correlations were coherent with numerical results, experimental data and flow visualization.