On sound generated aerodynamically I. General theory

  title={On sound generated aerodynamically I. General theory},
  author={Michael James Lighthill},
  journal={Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences},
  pages={564 - 587}
  • M. Lighthill
  • Published 20 March 1952
  • Physics
  • Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences
A theory is initiated, based on the equations of motion of a gas, for the purpose of estimating the sound radiated from a fluid flow, with rigid boundaries, which as a result of instability contains regular fluctuations or turbulence. The sound field is that which would be produced by a static distribution of acoustic quadrupoles whose instantaneous strength per unit volume is ρvivj + pij - a20ρδij, where ρ is the density, vi the velocity vector, pij the compressive stress tensor, and a0 the… 

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