When the incident angle is greater than a certain value, the steady-state pressure coefficient and the incident angle λ. When the incident angle changes, the pressure coefficient of a region decreases gradually. Whether the blade oscillates in the flow field. When the pressure coefficient gradient is positive, it is equivalent to the aerodynamic reaction force acting on the blades of the coal mine fan; when the pressure coefficient gradient is negative, it is equivalent to the aerodynamic positive force acting on the blades, the system is stable and exhibits stall disturbance.

If the opening of the deflector of the coal mine fan is not adjusted properly, or the impeller flow path, air flow path, filter, etc. are blocked, the actual flow rate will be lower than the planned flow rate. The direction of the airflow entering the impeller changes, and the airflow hits the working surface of the blade, forming a vortex or gas near the non-working surface of the blade of the coal mine fan. In addition, because the airflow entering the coal mine fan is unevenly distributed in each flow channel, the number of air vortices is also different.

Therefore, as long as we master the operation principle of coal mine fans, we can solve the problem of using them. to monitor.