抄録
In order to perform the evaluation of airbone dust in facilities for the atomic energy and to study the inhalation of radioactive aerosols, proper attention must be paid on the particle size distribution of the aerosols. Particularly, the monodispersed aerosols of proper size are required for the evaluation of internal exposure and the calibration of particle counters.
This paper describes the study on the mechanism of generation of aerosols from a spinning disc aerosol generator and the characteristics of the generated particles. Monodispersed aerosols of the size from 2 to 12μm with the geometric standard deviation of less than 1.2 could be generated from the solution of methylene blue by a 2cm-diameter glass spinning disc spun by an electric motor at 20000 to 40000rpm. The particle size or mass median diameter of the generated aerosols indicated a linear relationship with cube root of the concentration of feeding solution. Aerosols were collected by thermopositor and their sizes were measured by taking their microscopic photographs.
As to the relation between the surface tension of feeding solution and projecting distance of main droplet, the following results were obtained: The projecting distance of main droplet was in inverse proportion to the angular velocity of disc but was in proportion to the surface tension of feeding solution and to the square of K value of the equation (2). The experimental values agreed approximately with the calculated values.
