Influence of a Change in the Underlying Surface Roughness on the Formation of a Pattern from Radioactive Contamination

A. P. Elokhin, E. A. Kholodov, and M. V. Zhilina

The influence of a change in the surface roughness z0 on the air flow speed over this surface is considered. It is shown that a twofold change in the parameter (from 0.01 to 0.02) results in a disturbed speed of the air flow, which attenuates both with height and distance. The maximal disturbance can amount to 30% at a height of 5 m, it is already 3–5% at a height of 40 m, and it totally disappears at a height of 100 m. In the horizontal, the disturbance can spread for 1.5–2 km. The estimates of radioactive contamination of the underlying surface, under conditions of a nuclear power enterprise accident, demonstrated that the disturbance can lead to no less than a twofold error of the area of radioactive contamination.