Study On Mechanism Of Radon Progeny Collection Based On High Voltage Corona

It’s a new collecting method which has high collecting efficiency and permits the metal collecting-slices being used over and over again with the using of high voltage corona. After being born, a part of radon progenies rapidly combines with aerosol particles in the air to attached-progenies which has the same behavior and characteristics of common aerosol particles except the radioactivity. Aerosol particles will go through the processes of charged by ion-collision, of motion caused by electric field force and of deposition on the metal collecting-slice.The collecting efficiency is one of the parameters to value the collector. This paper analyzed the initial electric field of positive DC corona in the multi-needle to plate chamber with the PDE Tool box of MATLAB. We researched the impact of distance between needle and plate, corona voltage, temperature and relative humidity to the I-V characteristics of corona-discharge with theoretical analysis and experimental comparison.Secondly, based on the stability of corona discharging, we optimized the distance between needle and plate, the distribution of needles, and so on. At the same time, we had the mind that the second-collection is needless.At last, we researched the motion of aerosol particles in corona discharge field, and obtained the expression of collecting efficiency of collector which is impacted by many factors such as corona voltage, distance between needle and plate, temperature and relative humidity. This paper obtained the correction coefficient and correction formula of above factors and the measuring results coincided with ones of Alpha PM after correcting the efficiency of collector.