|
CSME 2019/12
Volume 40 No.6
:
703-709
|
|
Visualization of Mixing and Acoustic Characteristics of Elliptical Throat Jet with Passive Control
S. Manigandan a, K. Vijayaraja b, P. Gunasekar a, J. Devipriya a and S. Nithya a
aDepartment of Aeronautical Engineering, Sathyabama institute of science and technology, Chennai, India-600 119.
bDepartment of Aeronautical Engineering, KCG College of Technology, Chennai, India-600 119.
|
Abstract:
This paper deals about the effect of aspect ratio and related acoustic properties of jet issuing from non circular throat jets. The experimental program investigates the elliptical throat jet of aspect ratio of 2, 3 and 4 with passive control. The series of experiments conducted on both controlled and uncontrolled jet at NPR4 to find the core length and jet decay. The results are evaluated in perfectly expanded conditions, the results reveals that as the aspect ratio increases, the shear layer growth decrease. This leads to the axis switching at downstream. At perfectly expanded it is noticed that, due to the change in aspect ratio the shock cell structure sees appreciable change. At the aspect ratio of 2:1, the shock is oblique and it is replaced by normal shock at the aspect ratio of 3 and 4 jets. The variation of aspect ratio increases the amplitude of screech frequency. Implementation of passive control at the major axis of exit modifies the shock cell structure and which alters the amplitudes of screech tone frequency for aspect ratio of 2, 3 and 4 jets.
|
|
Keywords: Jet noise, mixing promotion, Supersonic Jet, Screech Frequency.
|
Download PDF
|
|
*Corresponding author; e-mail:
|
©
2019
CSME , ISSN 0257-9731
|