## 3 Results and Discussions
### Velocity and Temperature Distributions  
The calculated counter lines of velocity distributions on the selected planes can be seen in Figure 3. Depending on the velocity magnitude at the inlet of the air cleaners, the air flow was moved toward the ceiling of the room as the velocity decreased with the expansion ofthe plume. After that, an air circulation characterized by very small velocities, especially in the core region, occurred inside the room. Meanwhile, the contaminated indoor air was circulating by means of relatively low pressure at the outlet region of the air cleaner. By comparing the three flow rate cases, it can be seen that increasing the flow rate resulted in higher velocity values in the room. This caused stronger recirculation and mixing of the indoor air. This can also be observed from the calculated age of air distributions, as shown in Figure 3. When the mass flow rate increased, the age of the air decreased proportionally. In both cases, the higher values of the air age mainly occurred in the right upper core section of the room due to the establishment of a recirculation zone.  
The calculated counter lines of velocity distributions on the selected planes for the center location of the air cleaner can be seen in Figure 4. Similarly to the previous location cases, the air flow was moved toward the ceiling of the room as the velocity decreased with the expansion of the plume. However, the air stream divided itself among all regions once it had reached the ceiling, resulting in a more homogeneous distribution of clean air. After that, air circulation regions, characterized by relatively small velocities, especially in the core regions, occurred inside the room around the air cleaner. Meanwhile, the contaminated indoor air was circulating by means of relatively low pressure at the outlet region of the air cleaner. By comparing these two flow rate cases, it can be seen that increasing the flow rate resulted in higher velocity values in the room, similarly to the previous location cases. This caused stronger recirculation and mixing of indoor air. This can also be observed from the calculated age of air distributions, as shown in Figures 3 and 4. When the mass flow rate increased, the air age decreased proportionally. In both cases, the higher values of the air age mainly occurred in the upper core sections of the room due to the establishment of a recirculation zone.  
Figure 3: Contour plots of velocity, temperature, and air age in the middle of the room while the ACD was in position 1.  
The temperature distribution (Figures 3 and 4) shows that there was a relatively homogeneous distribution in the room. The change in air temperature remained below 1.5 \({}^{\circ}\)C. The air temperature at the locations close to the device was slightly warmer than in other parts of the room (+0.2 \({}^{\circ}\)C) when the air cleaner was in position 2, with this region expanding with increasing blowing speed. On the other hand, when the device was in position 1, this small irregularity in temperature was not observed (Figure 4). The most important reason for this is that, if the device was located in the middle of the room, it could distribute the fresh air better throughout the room. The same phenomenon was also observed in the velocity and air age distribution as mentioned above.