The structure of air turbulent motion inside the dome room - Primary Mirror (diameter 2.2 m) closed shaft at Siberian Lidar Station of V. E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science has been experimentally and theoretically studied. Research is needed to forecast a laser radiation distortion. Results of experiments performed using the ultrasonic compact portable weather station are presented. The main heat exchange directions of air flows inside the shaft are determined. Theoretical results have been obtained by numerical solving of boundary value problem for Navier-Stokes equations. Solitary large vortices (coherent structures, topological solitons) are observed inside the shaft. Coherent decay of such vortices generates the coherent turbulence. It is determined that inside the primary mirror shaft one may expect the weakening of phase fluctuations of optical radiation, and thus improvement the lidar optical imaging. This increases the efficiency of Lidar Station.