## 3 Results
### Design and Analysis of Orthogonal Test
#### 3.2.2 Analysis of the Influence of Test Factors on the Evaluation Index  
Figure 15a is the response surface diagram of the interaction between the inclination angle of the blade and the rotation speed of the vane-type film removal roller to the area ratio when the diameter of the roller is at the zero level (179.5 mm). Figure 15a shows that in the direction of the inclination angle of the blade, the area ratio gradually decreases as  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & \begin{tabular}{c} **Rotating Speed of** \\ **the Vane Type Film** \\ **Removal Roller \(x_{1}\)** \\ \end{tabular} & \begin{tabular}{c} **Inclination Angle** \\ **of the Blade \(x_{2.5}\)** \\ \end{tabular} & \
\begin{tabular}{c} **Diameter of the** \\ **Roller \(x_{3}\)** \\ \end{tabular} &
\begin{tabular}{c} **Evaluation Index** \\ **Area Ratio Y/\%** \\ \end{tabular} \\ \hline
1 & \(-1\) & \(-1\) & 0 & 28.04 \\
2 & \(1\) & \(-1\) & 0 & 12.61 \\
3 & \(-1\) & 1 & 0 & 19.31 \\
4 & \(1\) & 1 & 0 &  
the inclination angle of the blade increases. In the direction of the rotation speed of the vane-type film removal roller, the area ratio first decreases with increasing rotation speed of the vane-type film removal roller, and then the range of change tends to be flat. The response surface changes greatly along the direction of the rotation speed of the vane-type film removal roller. In addition, at the zero level, compared with the effect of the inclination angle of the blade on the area ratio, the effect of the rotation speed of the vane-type film removal roller on the area ratio is more significant.  
The main reasons for the above phenomenon are as follows: When the diameter of the roller is fixed, the space that can hold the gas in the film removal device remains unchanged. With the increase in the rotating speed of the vane-type film removal roller, the air inflow and pressure in the film removal device increase, and the phenomenon of inward air supply on the film conveying port surface decreases. At the same time, with the increase in the inclination angle of the blade, the gas distribution in the axial direction of the device is more balanced, and it is helpful to reduce the size of the vortex region at both ends of the device.  
Figure 15b is the response surface diagram of the interaction between the diameter of the roller and the rotation speed of the vane-type film removal roller to the area ratio when the inclination angle of the blade is at the zero level (15\({}^{\circ}\)). Figure 15b shows that with increasing roller diameter and rotating speed of the vane-type film removal roller, the overall change trend of the area ratio first decreases significantly and then gradually changes more gently. The response surface changes greatly along the direction of the rotation speed of the vane-type film removal roller. In addition, at the zero level, the influence of the rotation speed of the vane-type film removal roller on the area ratio is more significant than that of the roller diameter on the area ratio.  
The main reasons are as follows: the inclination angle of the blade is at the zero level, and the increase in the diameter of the roller leads to a decrease in the internal space of the device. With the increase in the rotating speed of the vane-type film removal roller, the internal air inflow of the device increases. Furthermore, under the combined action of the two factors, the internal pressure of the device increases, and the air inflow is sufficient, which leads to the gas gradually moving to both ends of the device. The difference in gas distribution at different positions decreases.