论文信息 - Influence of Turbulence on the Deposition Rate Constant of the Unattached Radon Decay Products

Influence of Turbulence on the Deposition Rate Constant of the Unattached Radon Decay Products

The deposition rate constants of the different unattached decay products of radon (222Rn) are evaluated from the measured radon and decay product concentrations in a 1-m3 chamber as a function of the degree of turbulence. The turbulence is induced by ventilation and/or generating heat. The coefficient of eddy diffusivity, ke, in the theoretical formula of Crump and Seinfeld for calculating the deposition rate is examined by fitting the Crump and Seinfeld formula to our experimental results. The expression for ke thus obtained is proportional to λ3 v (ventilation) and W 3/2 (generated heat). The deposition rate constant of 218Po is found to be about three times that of 214Pb, which means that the associated diameter of the 214Pb particle is about twice as large as the diameter of the 218Po particle. This difference could be due to the physical and chemical properties of the two elements

R. Dingenen | A. Poffijn | C. Landsheere | H. Vanmarcke

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