General layout of the experimental stand: 1 – plexiglass tube; 2 – support; 3 – copper sphere; 4 – blending chamber; 5, 15 – differential pressure gauge; 6 – fan; 7 – tank; 8 – ultrasonic mist generator; 9 – multimeter; 10, 17 – voltage controller; 11 – analogue output module; 12 – data collection module; 13 – computer; 14 – Pitot tube; 16 – air pump.