## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Test Series** & \(\begin{array}{c}p_{\text{max}}\\ \text{[kPa]}\end{array}\) & \(\begin{array}{c}p_{\text{stab}}\\ \text{[kPa]}\end{array}\) & \(\begin{array}{c}w_{\text{max}}\\ \text{[mm]}\end{array}\) & \(\begin{array}{c}w_{\text{stab}}\\ \text{[mm]}\end{array}\) & \(\begin{array}{c}\sigma_{\text{max}}\\ \text{[MPa]}\end{array}\) & \(\begin{array}{c}\sigma_{\text{stab}}\\ \text{[MPa]}\end{array}\) \\ \hline \multicolumn{7}{c}{+50 mL} \\ EXP & 0.783 \(\pm\) 0.006 & \(\begin{array}{c}0.701\pm 0.006\\ (-10.47\%)\end{array}\) & 0.102 \(\pm\) 0.100 & \(\begin{array}{c}0.100\pm 0.100\\ (-1.96\%)\end{array}\) & 0.967 \(\pm\) 0.038 & \(\begin{array}{c}0.899\pm\) 0.038 \\ (-7.03\%)\end{array}\) \\ FEM & - & 0.619 & - & 0.119 & - & 1.170 \\ ANA & - & 0.689 & - & 0.120 & - & 1.210 \\ \hline \multicolumn{7}{c}{\(-50\) mL} \\ EXP & \(-0.755\pm 0.007\) & \(\begin{array}{c}-0.699\pm 0.007\\ (-7.42\%)\end{array}\) & \(\begin{array}{c}-50\text{ mL}\\ -0.088\pm 0.008\\ (-0.00\%)\end{array}\) & \(\begin{array}{c}-0.088\pm 0.008\\ (-7.42\%)\end{array}\) & \(\begin{array}{c}-0.088\pm 0.008\\ (0.00\%)\end{array}\) & \(\begin{array}{c}-0.088\pm 0.008\\ -0.094\pm\) 0.038 \\ (-3.09\%)\end{array}\) \\ FEM & - & \(-0.623\) & - & \(-0.119\) & - & \(-1.282\) \\ ANA & - & \(-0.690\) & - & \(-0.120\) & - & \(-1.210\) \\ \hline \multicolumn{7}{c}{+100 mL} \\ EXP & \(1.496\pm 0.007\) & \(\begin{array}{c}1.367\pm 0.007\\ (-8.62\%)\end{array}\) & \(\begin{array}{c}0.007\\ (-8.62\%)\end{array}\) & \(\begin{array}{c}0.224\pm 0.006\\ (-1.69\%)\end{array}\) & \(\begin{array}{c}1.927\pm 0.064\\ (-6.43\%)\end{array}\) \\ FEM & - & 1.243 & - & 0.238 & - & 2.352 \\ ANA & - & 1.374 & - & 0.240 & - & 2.410 \\ \hline \multicolumn{7}{c}{\(-100\) mL} \\ EXP & \(-1.465\pm 0.007\) & \(\begin{array}{c}-1.360\pm 0.007\\ (-7.17\%)\end{array}\) & \(\begin{array}{c}-0.204\pm 0.008\\ (+0.49\%)\end{array}\) & \(\begin{array}{c}-0.205\pm 0.008\\ (-3.32\%)\end{array}\) & \(\begin{array}{c}-0.205\pm 0.008\\ (-3.32\%)\end{array}\) & \(\begin{array}{c}-0.205\pm 0.008\\ (-3.32\%)\end{array}\) \\ FEM & - & \(-1.258\) & - & \(-0.241\) & - & \(-2.349\) \\ ANA & - & \(-1.373\) & - & \(-0.240\) & - & \(-2.410\) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Results of experimental research, numerical and analytical calculations. Table 4 compares the results obtained with the applied methods in percentage terms. Summarizing all the results, it can be concluded that a good agreement between the numerical and analytical results was obtained; the results do not differ by more than 12% for the pressure difference and not more than 5.6% for the deflection and stress. In terms of small deformations and the level of analyzed loads, the analytical and numerical methods give practically the same results. In general, the methods of approximating the analyzed values (numerical and analytical) underestimate the values obtained from the tests by an average of 8% in terms of the pressure difference. In contrast, in terms of deflections and stresses, they overestimate them by an average of 16% and 32%, respectively. This observation indicates a certain rotational rigidity of the panes' edges, which limits their deformation and thus generates higher pressure inside the gap and lower stresses in glass. This phenomenon has also been reported in [5,6]. However, it should be emphasized that most calculation models and standard recommendations do not consider the possibility of flexible support of panes in IGUs.