COUNTERCURRENT DIAMETRIC FAN Russian patent published in 2021 - IPC F04D17/00 

FIELD: ventilation engineering.

SUBSTANCE: invention relates to the field of ventilation engineering; it can be used, in particular, in ventilation and heating systems and as an airflow generator, for example, in pneumatic systems of grain and seed cleaning machines. A countercurrent diametric fan comprises a case with an inlet and an outlet pipe and a flat wall separating them, equipped with a louver grille, an impeller installed in the case, mating, for example, in a logarithmic spiral with the inlet edge of the fan case, above the inlet, and a straight wall installed parallel to the separating flat wall and forming an inlet channel. Between the interface of the input edge of the fan case and the straight wall of the input channel, a connecting insert is installed, made, for example, in the form of an astroid truncated along the edges lying on the same axis, the truncation plane of which is congruent and lies on a straight line with the straight wall. The free edge of the astroid is directed to the fan impeller and makes a gap with it of 0.01…0.04 of the outer diameter D₂ of the wheel, and the distance from the input edge of the fan case and the free edge of the astroid corresponds to 0.47…0.5D2.

EFFECT: invention, in comparison with the prototype, has a more compact design and less metal consumption, more stable operation of the fan according to aerodynamic parameters due to

increase in the developed pressures and airflow, and a lower noise level.

1 cl, 1 dwg