## 4 Comparison with Previous Studies  
Here the developed numerical model is implemented based on CFD formulations and the FSI technique simultaneously using the ANSYS software, which is useful for developing numerical solutions of more accurate models. In order to validate the achieved results from the software analysis, we compared them with data and results of similar research assessments. To this end, we compared the results of particle deposition with the results obtained by [PERSON] et al. for a duct rigid model [19]. This comparison is shown in Table 2, where we specify the same conditions for our model. As can be seen, in some respects, the acceptable agreement is indicated between the data for the two studies. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c}{**Condition**} & \multicolumn{2}{c}{**Deposition Efficiency (\%)**} \\ \hline
**Generation Number** & **Particle Size (\(\upmu\)m)** & **Reported [19]** & **Computed Here** \\ \hline \multirow{4}{*}{\(18\)} & 1 & 2.7 & 3 \\  & 2 & 11 & 14.37 \\ \cline{1-1}  & 3 & 20 & 25.94 \\ \cline{1-1}  & 5 & 47.7 & 52.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of reported and computed results for the same conditions: Percentages of particle deposition in rigid model when gravity force acts along \(z\)-axis [\(0\), \(0\), \(-1\)]. Figure 11: Comparison between 1 and 5 \(\upmu\)m range particles deposition for over 18–22 generations with gravity acting on three orientations along the \(x\)-axis [\(-1\), \(0\), \(0\)], \(y\)-axis [\(0\), \(-1\), \(0\)] and \(z\)-axis [\(0\), \(0\), \(-1\)]. The local deposition distribution changes among the models of different generations with different \(\text{Re}_{\text{in}}\) combinations and values of the velocity ratio (particle settling velocity to mean flow velocity (\(\frac{V_{g}}{V}=\frac{p\ g\ kg^{2}}{184\text{\text{\text{W}}}}\)) (see Figure 6). There, the total deposition efficiency is observed to increase by increasing the generation number. However, for constant \((\frac{V_{g}}{V})\), the total efficiency number decreases by increasing the generation number (see Figure 12). This result is obtained from previous studies [20], and is also observed by [PERSON] and [PERSON] [7]. In order to compare the obtained results with those from previous experimental research, we note that, contrary to the experimental studies, where inhaled particles traverse the tree shape airways and reach the distal lungs, our modelling addresses the transport dynamics of the faction of certain injected particles in an ensemble of randomly. Therefore, we compare our results to higher deposition efficiencies of experimental studies because some particles are deposited in the upper airways and some particles remain entrained but do not reach the distal lungs before being exhaled. Despite this constraint, the published experimental data are consistent with our results, which provide more actual  
Figure 12: 2D and 3D local particle depositions for various generations for two-way particle coupling and moving wall model, for the following constant \((\frac{V_{g}}{V}=0.1)\). (a) 2 DG = 20, \(t=10\) s, \(Re=0.13\), \(DE=35.33\%\); (b) 3D; (c) 2 DG = 21, \(t=10\) s, \(Re=0.06\), \(DE=31.2\%\); (d) 3D; (e) 2 DG = 22, \(t=10\) s, \(Re=0.034\), \(DE=29.4\%\); (f) 3D. insights for alveolar modelling. During the resolutions, we show that the small particles having a small characteristic length scale are affected by diffusion-based parameters, i.e., tissue visco-elasticity properties are more intense than for larger particles. This consequence is confirmed by experimental studies [24] that report higher deposition efficiencies. In this study, the inhaled particles are input at the beginning of the lung and traverse more deeply into the alveoli. However, in another study [25] carried out under micro-gravity conditions, the deposition efficiency is higher than the expected values.