## 3 Model Verification  
### Comparing the Results with Numerical Data and Existing Experimental Data  
The NG model is based on [PERSON]'s boundary layer theoretical model, but the difference is that the NCG is CO\({}_{2}\) (not air), and the iterative calculation scheme used has been modified. Therefore, it is still meaningful to compare the simulated numerical result with [PERSON]'s data result. Table 4 lists some data compared with [PERSON]'s calculation results:  
In the current literature, experimental data on the condensation of steam-CO\({}_{2}\) mixture are scant. To verify the rationality of boundary layer simulation calculation as reported by [PERSON] [43], these data are selected for data verification purposes in this study. Comparison data are listed in Table 5. A data comparison method by [PERSON] et al. [16] is also used, in which the heat transfer reduction (\(q/q_{0}\)) is compared with [PERSON]'s experimental data and the boundary layer simulation data. Since the working fluid is a steam-air mixture, the NG model is applied with the NGC properties of air. As shown in Table 5, deviations between experimental and simulation data are around 6.08-14.68%.  
Experimental data for steam-CO\({}_{2}\) mixture condensation are severely lacking. Thus, we compare some of the data obtained by [PERSON] et al. [27] with the simulation results in Figure 3. In [PERSON] et al.'s study [27], an experiment was carried out on a \(5\times 5\) cm vertical plate surface, and the saturated mixture gas had a CO\({}_{2}\) percentage of 34.3%, with a total pressure of 101.325 kPa. As shown in Figure 3, the maximum deviation between experimental data and calculation results is 17.75%.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Numerical** & \multirow{2}{*}{\(F(\mathbf{0})\)} & \multirow{2}{*}{\(F^{*}(\mathbf{0})\)} & \multirow{2}{*}{\(\sqrt{\frac{p_{H}H_{t}}{\mu_{n}}}\frac{C_{p}(T_{n}-T_{n})}{h_{B}P_{r}}\)} & \(\frac{1}{H_{t}}\) & \(\frac{\mathbf{n}_{n}}{\mathbf{a}_{i}}\) \\ \hline \multirow{5}{*}{Sparrow [15]} & 0.1 & 0.36867 & 0.036827 & 1.3577 & 0.90510 \\  & 0.2 & 0.40612 & 0.099244 & 1.0076 & 0.82332 \\ \cline{1-1}  & 0.4 & 0.48325 & 0.25733 & 0.7772 & 0.69002 \\ \cline{1-1}  & 0.6 & 0.56300 & 0.43799 & 0.6849 & 0.58654 \\ \cline{1-1}  & 1 & 0.72887 & 0.82825 & 0.6037 & 0.43803 \\ \cline{1-1}  & 2 & 1.16943 & 1.8495 & 0.5407 & 0.24075 \\ \hline \multirow{5}{*}{This work} & 0.1 & 0.36865 & 0.036828 & 1.3577 & 0.90509 \\ \cline{1-1}  & 0.2 & 0.40609 & 0.099247 & 1.0076 & 0.82330 \\ \cline{1-1}  & 0.4 & 0.48321 & 0.25734 & 0.7772 & 0.68998 \\ \cline{1-1}  & 0.6 & 0.5629 & 0.43800 & 0.6849 & 0.58648 \\ \cline{1-1}  & 1 & 0.72880 & 0.82829 & 0.6038 & 0.43794 \\ \cline{1-1}  & 2 & 1.16929 & 1.8496 & 0.5408 & 0.24064 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Data comparison with Sparrow.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \(T_{\infty}\) **(K)** & \(\mathbf{a}_{\infty}\) & \(P\) **(kPa)** & \(q/q_{0}\) [43] & \(q/q_{0}\) **of This** & **Deviation** \\ \hline
383.15 & 0.017 & 145 & 0.4456 & 0.3857 & 13.44\% \\
383.15 & 0.0311 & 146.3 & 0.3255 & 0.3057 & 6.08\% \\
383.15 & 0.0457 & 147.75 & 0.2642 & 0.2479 & 6.17\% \\
373.15 & 0.0546 & 105.13 & 0.2377 & 0.2028 & 14.68\% \\
373.15 & 0.0226 & 102.91 & 0.3623 & 0.3375 & 6.85\% \\ \hline \hline \end{tabular}
\end{table}
Table 5: Data comparison with Othmer (\(T_{\infty}-T_{w}=5\) K).