Bernoulli Enthalpy: A Fundamental Concept in the Theory of Sound,
Abstract
A general theory of aerodynamic sound is developed. The basic equations of fluid mechanics are expressed in terms of velocity, enthalpy and entropy, and the velocity field is separated into irrotational and rotational parts with the latter being incompressible. A fundamental new concept, Bernoulli enthalpy, H, is introduced, again by analogy with homentropic-irrotational flow. It is shown that the source of the radiative sound field is the substantive rate of change of the Bernoulli enthalpy. Two basic conceptual issues of the modern theory of sound are resolved. First, the radiative sound is clearly separated from the source of sound with each part characterized by its own scalar field. Second, the Bernoulli source of sound is compact; i.e., it is confined to the region of rotational nonhomentropic flow.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1975
- Accession Number
- ADA040287
Entities
People
- Guido Sandri
- John E. Yates