## 3 Results  
### Analysis of Test Results  
To determine the fertilizer discharge effect of the spiral-pushing fertilizer applicator with different parameters in the simulation state, quadratic orthogonal rotation combination design experiments were used to analyze the simulation results comprehensively. The test and regression analysis results are shown in Table 3, Table 4, and Table 5, respectively.  
The results from Table 4 show that the filling coefficient regression model is significant, with a specific value of (\(p=0.0159<0.05\)), and its regression model mismatch term is not significant, with a specific value of (\(p=0.3360>0.001\)). For the filling coefficient test indicators, \(x_{1}x_{2}\) has an extremely significant impact, with \(x_{1}\), \(x_{2}\), \(x_{1}x_{2}\), and \({x_{2}}^{2}\) having a significant impact, while the other factors have no significant impact.  
The results from Table 5 show that the regression model for the particle axial velocity coefficient is extremely significant (\(p=0.0019<0.001\)), and its regression model mismatch term is not significant (\(p=0.3193>0.001\)). For the particle axial velocity coefficient test indicators, \(x_{1}\) and \(x_{3}\) have an extremely significant impact, while the other factors have no significant impact.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Code**} & \multicolumn{3}{c}{**Factor**} \\ \cline{2-4}  & \(x_{1}\)/\% & \(x_{2}\)/\% & \(x_{3}\)/\(r\)-Min\({}^{-1}\) \\ \hline
1.682 & 200.00 & 125.00 & 220 \\
1 & 179.73 & 119.93 & 181.49 \\
0 & 150.00 & 112.50 & 125.00 \\ \(-1\) & 120.27 & 105.07 & 68.51 \\ \(-1.682\) & 100.00 & 100.00 & 30.00 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Factor-level coding table.  
Excluding insignificant factors from the regression equation, the regression equations for the filling coefficient and particle axial velocity coefficient are:  
\[\left\{\begin{array}{rl}\mu=429.973+1.557x_{1}-7.760x_{2}+0.039x_{3}\\ -0.022x_{1}x_{2}+0.003{x_{1}}^{2}+0.047{x_{2}}^{2}\\ y_{1}=59.95-0.27x_{1}+0.07x_{3}\end{array}\right. \tag{25}\]  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & \multicolumn{4}{c}{**Filling Coefficient \(\mu\%\)**} \\ \hline
\begin{tabular}{c} **Source of** \\ **Variance** \\ \end{tabular} & \multirow{2}{*}{**Square SUM**} & \multicolumn{2}{c}{**Degree of**} & \multirow{2}{*}{**Mean Square**} & \multirow{2}{*}{**\(F\)-Value**} & \multirow{2}{*}{**\(p\)-Value**} \\ \hline Model & 697.14 & 9 & 77.46 & 3.74 & 0.0159 \\ \(x_{1}\) & 114.10 & 1 & 114.10 & 5.50 & 0.0355 \\ \(x_{2}\) & 102.60 & 1 & 102.60 & 4.95 & 0.0445 \\ \(x_{3}\) & 67.69 & 1 & 67.69 & 3.26 & 0.0940 \\ \(x_{1}x_{2}\) & 186.44 & 1 & 186.44 & 8.99 & 0.0103 \\ \(x_{1}x_{3}\) & 15.68 & 1 & 15.68 & 0.76 & 0.4003 \\ \(x_{2}x_{3}\) & 6.34 & 1 & 6.34 & 0.31 & 0.5898 \\ \(x_{1}^{2}\) & 88.63 & 1 & 88.63 & 4.27 & 0.0592 \\ \(x_{2}^{2}\) & 108.61 & 1 & 108.61 & 5.24 & 0.0395 \\ \(x_{3}^{2}\) & 7.63 & 1 & 7.63 & 0.37 & 0.5546 \\ Residual & 269.58 & 13 & 20.74 & & \\ Misfit term & 123.31 & 5 & 24.66 & 1.35 & 0.3360 \\ Pure error & 146.27 & 8 & 18.28 & & \\ Total variation & 966.72 & 22 & & & \\ \hline \hline \end{tabular}
\end{table}
Table 4: Filling coefficient analysis table.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & \multicolumn{2}{c}{**Test Factor**} & \multicolumn{2}{c}{**Test Indexes**} \\ \cline{2-5} \multicolumn{1}{c}{**Code**} & \(\mathbf{x_{1}\%}\) & \(\mathbf{x_{2}\%}\) & \(\mathbf{x_{3}/r\cdot Min^{-1}}\) & \(\mathbf{y_{1}\%}\) & \(\mathbf{\mu\%}\) \\ \hline  
\hline \hline \end{tabular}
\end{table}
Table 3: Schemes and results of tests.