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Transport of energy by disturbances in arbitrary steady flows

Published online by Cambridge University Press:  26 April 2006

M. K. Myers
M. K. Myers
Affiliation:
The George Washington University, Joint Institute for Advancement of Flight Sciences, Mail Stop 269, NASA Langley Research Center, Hampton, VA 23665, USA
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Abstract

An exact equation governing the transport of energy associated with disturbances in an arbitrary steady flow is derived. The result is a generalization of the familiar concept of acoustic energy and is suggested by a perturbation expansion of the general energy equation of fluid mechanics. A disturbance energy density and flux are defined and identified as exact fluid dynamic quantities whose leading-order regular perturbation representations reduce in various special cases to previously known results. The exact equation on disturbance energy is applied to a simple example of nonlinear wave propagation as an illustration of its general utility in situations where a linear description of the disturbance is inadequate.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 226 , May 1991 , pp. 383 - 400
Copyright
© 1991 Cambridge University Press

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