## 3 Results and Discussions
### Airflow Prediction  
Velocity profiles are presented in Figure 20 for the first three scenarios of the outdoor air curtain in the summer season (SET 1-3: 7 th-27 th July). Each velocity profile is represented in correlation with other parameters that influence the operation of the facade, namely the wind speed, the exterior temperature, and the air temperature inside the DSF channel. The velocities were measured at three points at different heights in the channel: in the middle of the inlet section (h = 0.05 m), in the middle of the channel (h = 1.4 m), and in the middle of the outlet section (h = 2.75 m). The results in each measurement point and the correlation with the day and time are presented in Tables 7-9 for each period (SET 1-3). and a descendant one near the exterior glazing, which validates the numerical results obtained in the previous works [37; 39]. Due to the vertical and lateral openings, the velocities in the third scenario are lower relative to the first two ones, Figure 20. The forced ventilation mode determines the turbulent character of the flow in the middle of the channel with a variation of velocities between 0.25-0.42 m/s (Figure 20b). In the natural airflow ventilation scenarios (Figure 20a,c), the velocities inside the channel are almost constant for the lateral openings and a slight variation of 0.25-0.31 m/s for the lateral and vertical openings. This is because the air velocity at the inlet section depends on the wind speed and a higher temperature of the air inside the channel determines higher velocities in natural convection. Figure 20: Air velocity profiles inside the DSF channel for ventilation modes of summer conditions: (**a**) SET 1-natural ventilation with lateral opening, (**b**) SET 2-forced ventilation with lateral opening, (**c**) SET 3-natural ventilation with vertical and lateral openings. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Day**} & **Measuring** & \multicolumn{3}{c}{**Air Velocity, v**} & \multicolumn{2}{c}{**v\({}_{\text{med}}\)**} & \multicolumn{2}{c}{**Q\({}_{\text{v}}\)**} & \multicolumn{2}{c}{**V\({}_{\text{wind}}\)**} & \multicolumn{2}{c}{**T\({}_{\text{e}}\)**} & \multicolumn{2}{c}{**T\({}_{\text{cav}}\)**} \\ \cline{3-10} \multicolumn{1}{c}{**Hour**} & **Point** & & **(m/s)** & & **(m/s)** & **(m3/h)** & **(m/s)** & **(\({}^{\circ}\)C)** & **(\({}^{\circ}\)C)** \\ \hline \multirow{2}{*}{12 July 10:00} & Inlet & 0.41 & 0.6 & 0.52 & 0.51 & 367 & & & \\  & h = 1.4 m & 0.23 & 0.21 & 0.18 & 0.21 & - & 0.4 & 29.2 & 39.3 \\  & Outlet & 0.62 & 0.68 & 0.72 & 0.67 & 482 & & & \\ \hline \multirow{2}{*}{12 July 15:00} & Inlet & 0.36 & 0.51 & 0.54 & 0.47 & 338 & & & \\  & h = 1.4 m & 0.23 & 0.22 & 0.2 & 0.22 & - & 2.7 & 26.9 & 37.9 \\  & Outlet & 0.6 & 0.52 & 0.68 & 0.60 & 432 & & & \\ \hline \multirow{2}{*}{12 July 17:00} & Inlet & 0.43 & 0.56 & 0.47 & 0.49 & 353 & & & \\  & h = 1.4 m & 0.2 & 0.21 & 0.18 & 0.20 & - & 0.9 & 22.1 & 25.5 \\  & Outlet & 0.74 & 0.65 & 0.72 & 0.70 & 504 & & & \\ \hline \multirow{2}{*}{13 July 12:00} & Inlet & 0.59 & 0.52 & 0.64 & 0.58 & 418 & & & \\  & h = 1.4 m & 0.23 & 0.21 & 0.18 & 0.21 & - & 1.3 & 27.4 & 40.9 \\  & Outlet & 0.4 & 0.56 & 0.61 & 0.52 & 374 & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Air velocities at different heights in the DSF channel for SET 1: 07 th–13 th July.