Electrical aspects of rainout

Rainout commonly denotes the aggregate of phenomena associated with precipitation scavenging of radioactivity from a cloud of nuclear debris that is within a natural rain cloud. (In contrast, the term, washout, is applicable when the nuclear cloud is below the rain cloud and the term, fallout, commonly denotes the direct gravitational settling of contaminated solid material from a nuclear cloud.) Nuclear debris aerosols may be scavenged within natural clouds by a variety of different physical processes which may involve diffusion, convection, impaction, nucleation, phoresis, turbulence, and/or electricity among others. Processes which involve electrical aspects are scrutinized for their susceptibility to the intimate presence of the radioactive-cloud environment. This particular choice of electrical processes is not accidental. Nearly all of the listed processes were examined earlier by Williams. His rough estimates suggested that electrical effects, and to a lesser extent turbulence, could enhance the scavenging of those submicron aerosols which reside in the size-range that bridges the minimum in the scavenging rate coefficient which is commonly called the Greenfield gap. This minimum in the scavenging-rate coefficient is created by the simultaneous reduction of scavenging via diffusion and the reduction of scavenging via inertial impaction. However, Williams omitted the specific influence of a radioactive environment. This report aims to remedy this omission

Weak-shock theory for spherical shock waves

We develop weak shock theory in a form which would allow us to utilize output from a hydrodynamic code (e.g. KOVEC) as either an initial or boundary condition and then follow the wave evolution to much greater distances than the codes themselves can attain