# On sound generated aerodynamically I. General theory

@article{Lighthill1952OnSG, 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}, year={1952}, volume={211}, pages={564 - 587} }

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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