Article

The effects of temperature on supersonic jet noise emission

02/1992;
Source: NTRS

ABSTRACT This paper examines the generation of sound produced by high temperature supersonic jets. In particular, the question of the importance of supersonic instability waves to noise emission is considered relative to the role of Kelvin-Helmholtz (K-H) instability waves. Here, these waves are taken to be synonymous with the Mach emission process. Jet total temperatures from 313 to 1534 K are investigated using an axisymmetric water cooled supersonic nozzle designed for Mach 2. The aerodynamic and acoustic results of this study indicate that the dominant noise contributors are the K-H waves over the entire temperature range. Good agreement between measured and numerically predicted plume properties are obtained and an elliptic nozzle is used to demonstrate reduction of the K-H waves.

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    Numerische Mathematik 04/2012; 113(4):555-600. · 1.32 Impact Factor
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Keywords

acoustic results
 
axisymmetric water
 
dominant noise contributors
 
entire temperature range
 
Jet total temperatures
 
K-H
 
K-H waves
 
Kelvin-Helmholtz
 
Mach 2
 
Mach emission process
 
noise emission
 
paper examines
 
plume properties
 
synonymous
 
temperature supersonic jets
 

John M. Seiner