Theory of Acoustic Radiation Pressure
Technical rept. no. 1
CALIFORNIA INST OF TECH PASADENA NORMAN BRIDGE LAB OF PHYSICS
Pagination or Media Count:
A detailed study is presented of the acoustic radiation pressure exerted by plane compressional waves in nonviscous liquids and gases upon a plane obstacle. The present report is largely a further development and extension of a very comprehensive and penetrating treatment of acoustic radiation pressure by L. Brillouin. The theory of plane waves in liquids is extended to the case of finite amplitudes. From this more general point of view the effects at small amplitudes are derived and discussed in detail. Formulas are given for normal and oblique incidence of the acoustic beam for small amplitudes, valid for any reflection coefficient of the receiving plane. The radiation pressure at finite amplitudes upon a perfect absorber is calculated. Special consideration is devoted to the actual physical processes involved the meaning of the so called Rayleigh pressure and Langevin pressure is discussed. For gases the radiation pressure as well as the Rayleigh pressure in progressive and standing waves are computed. The report concludes with an assembly of the chief equations.