An original approach to describe airflow in the thin conic diffusor is suggested. It is based on approximate analytic solution of continuity equation. In addition simplified model of turbulence is combined. Reliability of derived formula is confirmed by comparison with finite-element solution for designed experimental setup. The elaboration is intended to direct computer simulation of multiphase flow.

Keywords: dust-air mixture, aspiration systems, turbulence, finite element modeling, separation diffuser, digital twin

Permafrost occupies about 25 percent of the world's area and spreads across the north of America, Europe, Asia, as well as the islands of the Arctic Ocean and Antarctica. In Russia, a considerable part of the population lives and works in the regions of the Far North, where mining is rapidly developing in conditions of permafrost. This is where the erection of the foundations is an important issue.

Keywords: pile foundations, permafrost, drilling, oil production, land, territory, deformations, soil, installation, screw piles