Variation of 220Rn progeny concentration with time under different wind speeds in 220Rn chamber

By changing the wind speed in the internal flow field of the device, the change process of the concentration of 220Rn daughters (212Pb and 212Bi) with time is recorded in detail. The experimental results show that these concentration values gradually accumulate from the initial zero until they reach a stable equilibrium state.

By analyzing these data, we can accurately obtain the concentration value in the equilibrium state and the specific time required to achieve this equilibrium state.