# Study on the Influence of Dust Removal Fan Structure Parameters on Dust Removal Performance
## 4 Numerical Simulation Results and Analysis
### Influence of the Number of Driven Impeller Blades on the Performance of Dust Removal Fan  
The number of driven impeller blades of the original dust removal fan is 10. Four dust removal fan impeller models with different numbers of driven impeller blades were established. The driven impeller blade numbers of each model are shown in Table 8.  
In the numerical simulation of four dust removal fan models with a different number of driven impeller blades, the inlet speed is set to 16.405 m/s and the speed of the driving impeller is set to 2900 r/min. It is assumed that the mass of the driven impeller remains unchanged at 20 kg for all four models, and the dust particle size is set to 10 \(\upmu\)m during the discrete phase simulation. The numerical simulation results are summarized in Table 9.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Model**} & \multirow{2}{*}{**Total Pressure/Pa**} & \multirow{2}{*}{**Static Pressure/Pa**} & \multirow{2}{*}{**Impeller Shaft Power/\&KW**} & \multirow{2}{*}{**Total Pressure Efficiency/\%**} & \multirow{2}{*}{**Static Pressure Efficiency/\%**} & \multirow{2}{*}{**Diven Impeller Efficiency/\%**} \\  & & & & & & \\ \hline Using C-4 & & & & & & \\ airfoil & 1546.77 & 1226.94 & 20.526 & 49.71 & 39.43 & 81.31 \\ Arc plate airfoil & & & & & & \\ of equal & 1548.84 & 1228.27 & 23.943 & 42.67 & 33.84 & 84.85 \\ thickness & & & & & & \\ \hline \hline \end{tabular}
\end{table}
Table 7: Comparison of simulation results of dust removal fan models with different airfoil profiles for driving impeller blades.
The relationship between the total pressure efficiency, static pressure efficiency, and dust removal efficiency in the table, and the number of driven impeller blades, is drawn into a line chart, as shown in Figure 16.  
According to the numerical simulation results, when the air volume and the mass of the driven impeller remain constant, the shaft power of the driving impeller of the dust removal fan gradually increases with the increase in the number of driven impeller blades, while the speed of the driven impeller gradually decreases. Additionally, the total pressure and static pressure values initially increase and then decrease, and the total pressure efficiency, static pressure efficiency, and dust removal efficiency gradually decrease. This pattern is similar to the change observed in the dust removal fan performance when the number of driving impeller blades decreases. This is because, with the increase in the number of driven impeller blades, the moment of inertia of the driven impeller increases, resulting in a larger shaft power of the driving impeller. However, the change in the number of driven impeller blades has little influence on the total pressure and static pressure values of the dust removal fan, leading to a reduction in both total pressure efficiency and static pressure efficiency. Additionally, increasing the number of blades on the driven impeller reduces the area of the flow channel through which the air flows, hindering the passage of the airflow. This, coupled with the increased moment of inertia of the driven impeller, significantly reduces the speed of the driven impeller. Consequently, the torque exerted by the rotation of the driven impeller decreases the dust particles in the dusty airflow, leading to a reduction in the centrifugal force of the dust particles and a decrease in dust removal efficiency.  
Figure 16: Influence of blade number of driven impeller on dust removal performance. (**a**) Number of driven impeller blades—total pressure efficiency; (**b**) number of driven impeller blades—static pressure efficiency; (**c**) number of driven impeller blades—dust removal efficiency.