# Wind Pressure Coefficient on a Multi-Storey Building with External Shading Louvers
## 5 Conclusions  
Taking into account rotation angle of shading louvers, this study investigated the distribution of wind pressure coefficient of a multi-storey building, with single-shaded louvers, through CFD simulation, in order to analyse the potential ventilation capacity of the shaded building. A comparison for validation was performed between the numerical results and data from the previous study. To investigate the wind pressure distribution in detail, the studied outside surfaces were divided  
Figure 16: Difference \(\Delta\overline{\mathcal{C}_{\mathrm{p}}}\) of average wind pressure coefficient \(\overline{\mathcal{C}_{\mathrm{p}}}\) between different shaded conditions and the non-shaded condition for **(a)** F5; **(b)** F4; **(c)** F3; **(d)** F2; **(e)** F1. into seven rows and five floors to obtain the average wind pressure coefficients of different rooms. The local wind pressure coefficients were also measured along central lines of different rows and floors. The rotation angle of louvers was taken as 0\({}^{\circ}\), 15\({}^{\circ}\), 30\({}^{\circ}\), 45\({}^{\circ}\), 60\({}^{\circ}\) and 75\({}^{\circ}\). Through the analysis of the impact of shading louvers, some conclusions are provided as follows:  
* The validation of the studied building shows a small deviation between the numerical data and the data from the previous study. The average absolute deviation is 0.046 for wind pressure coefficient \(C_{\text{P}}\) and 0.068 for normalized velocity \(U/U_{\text{ref}}\). The Grid Convergence Index of \(U/U_{\text{ref}}\) and \(C_{\text{P}}\) for the reference case is 0.37%, and 1.8%, respectively. Therefore, the parameters of the simulation cases are feasible for the shaded building, and the computational settings is useful for further case studies of shaded buildings. * In general, the fluctuations of \(C_{\text{P}}\) on the windward and roof surfaces are mostly stronger than those on the lateral and leeward surfaces along the measurement lines. These results indicate that when the ventilation openings located on the roof and windward facade with louvers, the ventilation routes can lead to larger fluctuations of ventilation rate. In building design, it is important to diagnose the risks of inadequate ventilation for shaded buildings, especially those with roof ventilation systems. * The stagnation zone of the windward surface has the highest average wind pressure coefficient \(\overline{C_{\text{P}}}\). For most floors and rows, \(\overline{C_{\text{P}}}\) decreases with a higher rotation angle \(\theta\). And \(\overline{C_{\text{P}}}\) has the greatest reduction for all floors when \(\theta\) turns from 60\({}^{\circ}\) to 75\({}^{\circ}\). These results indicate that ventilation openings on the stagnation zone contribute to higher ventilation rate for the windward facade with louvers. When the rotation angle is taken for more than 60\({}^{\circ}\), it is essential to avoid bad indoor wind environment for rooms with ventilation openings located on the shaded facade. Overall, several parameters of wind pressure coefficient distribution were investigated in this study to gain a greater understanding of fluctuations in wind characteristics caused by the presence of external shading louvers. These kinds of data provide a wider perspective for building engineers and designers to understand the wind-induced fields around shaded buildings and improve the indoor environment in buildings with external shading louvers. Conceptualization, J.Z., Q.T. and L.L. ; methodology, J.Z. and Q.T. ; software, J.Z. ; validation, J.Z. and Q.T. ; formal analysis, J.Z., Q.T. and L.L. ; investigation, J.Z. ; writing--original draft preparation, J.Z. ; writing--review and editing, J.Z., Q.T. and L.L. ; visualization, J.Z. All authors have read and agreed to the published version of the manuscript. This research was funded by the National Natural Science Foundation of China, Grant No. 51508225; Natural Science Foundation of Fujian Province, Grant No. 2018J01486; Foundation of Education Department of Fujian Province, Grant No.