## 3 Results and Discussions
### CADR Values  
Table 3 presents the clean air delivery rate (CADR) values for all considered cases. It can be seen that increasing mass flow rates resulted in an increase in CADR values. It should be mentioned that higher CADR values represent a better performance. Surprisingly, the center placement of the air cleaner showed a better performance compared to the wall side cases. This may be caused by longer air stream distributions resulting in slower air velocities at the faraway locations in the room, so that particles may stay longer in the air. These results could also be explained by using the mean air age values given in Table 2. Smaller mean age values resulted in higher CADR values. In this respect, it can be said that both performance metrics support each other's findings. These observed results show that the air distribution performance of a ventilation system or cleaning device used in a closed environment can be analyzed by using these two different methods. Table 3 also shows that CADR and collection efficiency values for larger particles were about 2-7% better than those for smaller particles. It means that smaller particles spent a longer time being suspended in the room air. Table 3 also shows the efficiency of the air cleaner device. Parallel to the CADR values, better collection efficiency values were observed with increasing flow rates. The maximum efficiency value of 86% for the ACD was obtained in relation to the center location and the highest flow rate. The efficiency of the ACD was in the range of 71% to 87%. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline Flow rate & 126.7 (m\({}^{3}\)/h) & \multicolumn{3}{c}{190.1 (m\({}^{3}\)/h)} & \multicolumn{3}{c}{253.4 (m\({}^{3}\)/h)} \\ \hline \multicolumn{7}{c}{Mean Age of Air (s)} \\ \hline Location & Mean & Max & Mean & Max & Mean & Max \\ \hline Wall Side (Pos. 1) & 802.2 & 1012.8 & 539.4 & 607.5 & 401.6 & 444.1 \\ \hline Center (Pos. 2) & 774.3 & 827.8 & 516.2 & 545.6 & 387.2 & 409.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Maximum and mean air age (s) values for different flow rates. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Position** & \multicolumn{6}{c}{**Wall Side Placement (Position 1)**} \\ \hline Flow Rate & m\({}^{3}\)/h & 126.7 & 126.7 & 190.1 & 190.1 & 253.4 & 253.4 \\ \hline \hline d\({}_{\text{P}}\) & \(\mu\)m & 1 & 10 & 1 & 10 & 1 & 10 \\ \hline CADR & m\({}^{3}\)/h & 89.4 & 93.0 & 134.4 & 145.2 & 179.4 & 186.6 \\ \hline \hline \(\eta\) & \% & 71 & 73 & 71 & 76 & 71 & 74 \\ \hline k\({}_{\text{e}}\) & min\({}^{-1}\) & 0.055 & 0.057 & 0.08 & 0.086 & 0.105 & 0.109 \\ \hline \(\Delta\)t\({}_{10\%}\) & min & 41.86 & 40.39 & 28.78 & 26.77 & 21.93 & 21.12 \\ \hline \hline \(\Delta\)t\({}_{1\%}\) & min & 83.73 & 80.79 & 57.56 & 53.55 & 43.86 & 42.25 \\ \hline Position & \multicolumn{6}{c}{Center Placement (Position 2)} \\ \hline Flow Rate & m\({}^{3}\)/h & 126.7 & 126.7 & 190.1 & 190.1 & 253.4 & 253.4 \\ \hline d\({}_{\text{P}}\) & \(\mu\)m & 1 & 10 & 1 & 10 & 1 & 10 \\ \hline CADR & m\({}^{3}\)/h & 100.2 & 109.2 & 154.2 & 165.0 & 204.6 & 217.2 \\ \hline \hline \(\eta\) & \% & 79 & 86 & 81 & 87 & 81 & 86 \\ \hline k\({}_{\text{e}}\) & min\({}^{-1}\) & 0.061 & 0.066 & 0.091 & 0.097 & 0.119 & 0.126 \\ \hline \hline \(\Delta\)t\({}_{10\%}\) & min & 37.7 & 34.9 & 25.3 & 23.7 & 19.3 & 18.3 \\ \hline \(\Delta\)t\({}_{1\%}\) & min & 75.5 & 69.8 & 50.6 & 47.5 & 38.7 & 36.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Predicted performance parameters of the air cleaner device by using the CADR method. For each case, the calculated total decay rate, \(\rm{k_{e}}\), values are also given in Table 3. Statistical works with the particle tracking data were performed by using an Excel spreadsheet. In the calculation of \(\rm{k_{e}}\), \(\rm{R^{2}}\) values were greater than 0.98 for all cases considered. Higher \(\rm{k_{e}}\) values resulted in a faster decrease in particle concentration in the room air.