The current study involves the investigation of the flow characteristics for a rectangular nozzle of aspect ratio 2:1 (De = 0.813 in) through streamwise Particle Image Velocimetry (PIV). The effect of temperature ratio (TR) on the flow characteristics for nozzle pressure ratio (NPR) of 2.5, 3.0, 3.5, 3.67, 4.0 & 4.5 were observed. PIV was used to extract the flow velocity and the Turbulent Kinetic Energy (TKE). Comparisons were drawn between unheated TR 1.1 and heated TR 2.0 & 2.6. Increase in the NPR lead to an increase in the potential core and the effect was inverse for an increase in jet temperature. Screech, observed at NPR 3.0 lead to jet flapping and spreading in the Minor axis plane. Acoustic study was conducted using a near-field microphone array to study the OASPL for various conditions of temperature namely TR 1.0 & 2.8. The screech condition led to an elevated noise level when compared to other conditions of 5dB at TR 1.0. A shift in the noise source was observed at higher temperature of TR 2.8 along the jet axis and a change in source from screech instabilities to broadband shock associated noise and a 5dB increase for NPR 3.0.
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