Rayleigh’s theory

To account for the effect of liquid viscosity on liquid jet breakup, Weber extended Rayleigh s theory to a more general theory for low-velocity j et breakup. In Weber s theory it is assumed that... 

For particles below 200 nm, Rayleigh s theory holds, which considers the scattering intensity to be proportional to the 6th potency of the particle diameter. Both Fraunhofer s and Rayleigh s theories are only approximations of Mie s theory which claims that the scattering intensity depends on the scattering angle, the absorption, the size of the particles as well as on the refractive indices of both the particles and the dispersion medium. 

In 1936, Avsec (A2) confirmed Rayleigh s theory in a rough way for air layers confined between metal plates spaced from 1.1 to 6.3 cm apart. The onset of convection was detected visually by means of smoke within the chamber. In 1938, Schmidt and Saunders (S5) repeated the experiments of Schmidt and Milverton, using air as well as water, and obtained an average critical R of 1750. In 1958, an extensive study by Silveston (S9) using the Schmidt-Milverton technique confirmed the Rayleigh theory for four liquids in addition to water, for depths from 1.45 to 13 mm. Silveston s results yielded a critical Rayleigh number of 1700 51. 

The essay, Bohr s first scientific paper, determined the surface tension only of water but also uniquely extended Rayleigh s theory. It won a gold medal from the academy. It was an outstanding achievement for someone so young and it set Bohr s course for physics. Unlike mathematicized philosophy, physics was anchored solidly in the real world. 

Wave motion at a surface or interface can result from both gravitational and capillary forces. Lx)rd Rayleigh studied the break-up of a jet of liquid into a gas [20]. Capillary forces make liquid jets unstable when their length, L, exceeds their circumference. Axisymmetric disturbances of the surface grow in amplitude until the jet is pinched off (Figure 13). Rayleigh s theory correctly predicted the drop size and the dependence of L on surface tension. Subsequent work [21] for liquid/gas and liquid/liquid jets has shown that the breakup is dependent upon ... 

Subsequent work by Einstein [2], Debye [3], and others [4-6] extended Rayleigh s theory to the treatment of simple liquids and dilute polymer solutions. For polymers, an optical constant K may be defined... 

The control of the size of the particles in glass-ceramics is fundamental as it plays a key role in the transparency of the glass-ceramics. Indeed, according to Rayleigh s theory, the intensity of light scattered by a particle follows the relation ... 

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