How does Lighthill's theory relates to noise energy generator?
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Lighthill's theory of aerodynamic sound is based on an analogy that relates the noise generated by fluctuating sound sources to the radiated sound. The theory considers monopole, dipole, and quadrupole sources and calculates the equivalent acoustic sources in a turbulent flow. The theory has been used to predict the noise generated by subsonic flows, including the effects of mean flow on sound propagation . Lighthill's equation, derived from the analogy, is used to compute the noise produced by subsonic flows and has been shown to accurately predict mean flow effects on sound propagation . The theory has also been used to calculate the acoustic radiation from turbulent flows, with the resulting acoustic power following a power law of velocity and showing the efficiency of conversion of turbulent kinetic energy into sound . Lighthill's theory is widely used in the study of aerodynamic noise and has been applied to various flow scenarios .
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| The paper discusses how the Lighthill quadrupole radiation is an important mechanism in the noise generation of supersonic and transonic propellers. It provides simple formulas to predict the far-field acoustic pressure generated by unswept blades accurately and quickly. However, it does not directly mention the term "noise energy generator." | |
6 Citations | Lighthill's theory relates to the conversion of turbulent kinetic energy into radiated sound, showing low efficiency due to fluctuations in the rate of dilatation accompanying fluctuations in the non-linear rate of energy transfer. |
| Lighthill's theory, known as the Lighthill analogy, is used to predict the noise generated by turbulent flows. It involves solving the incompressible Navier-Stokes equations and the acoustic equation to compute the acoustic density fluctuations caused by the flow. | |
28 May 2001 | Lighthill's theory relates to noise energy generation by using an integral formulation of Lighthill's equation to compute the noise radiated by a jet. |
| Lighthill's theory relates to the generation of acoustic noise by computing the source field and then estimating the sound field in three steps, including computing the acoustic noise. |
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