## 3 Result Discussion  
### Aerodynamic Comparison  
The results of the aerodynamic force and moment coefficient calculations are provided in Table 2, which were nondimensionalized based on the inflow density (\(\rho\)), velocity (\(V\)), characteristic area, and device length, as defined in Equation (21):  
\[ \begin{array}{l}C_{x}=F_{x}/\left(0.5\rho V^{2}S_{c}\right)\\ C_{y}=F_{y}/\left(0.5\rho V^{2}S_{c}\right)\\ C_{z}=F_{z}/\left(0.5\rho V^{2}S_{c}\right)\\ m_{x}=M_{x}/\left(0.5\rho V^{2}S_{c}L_{c}\right)\\ m_{y}=M_{y}/\left(0.5\rho V^{2}S_{c}L_{c}\right)\\ m_{z}=M_{z}/\left(0.5\rho V^{2}S_{c}L_{c}\right)\end{array}  \tag{21}\]  
where \(\rho=1.225\) kg\(\cdot\)m\({}^{3}\), \(V=110\) m/s, \(S_{c}=0.149\) m\({}^{2}\), and \(L_{c}=0.5\) m. Because the stress of the components (ears), the moment characteristics, and the other parameters of the swing ears need to be considered, the lift and drag were used for the full-mode results, and all the moments and lateral forces were used for the half-mode integration results. \begin{table}
\begin{tabular}{c c c c c c c c} \hline
**Working Condition** & **Component** & **Cx** & **Cy** & **Cz** & **mx** & **my** & **mz** \\ \hline \multirow{4}{*}{\(1\)} & body & \(-0.227\) & \(0.302\) & \(0.426\) & \(0.0159\) & \(-0.0147\) & \(0.0114\) \\ \cline{2-8}  & ear & \(-0.141\) & \(0.559\) & \(-0.272\) & \(-0.1083\) & \(0.0170\) & \(0.0389\) \\ \cline{2-8}  & total & \(-0.369\) & \(0.862\) & \(0.154\) & \(-0.0924\) & \(0.0024\) & \(0.0503\) \\ \hline \multirow{4}{*}{\(2\)} & body & \(0.142\) & \(0.204\) & \(0.356\) & \(0.0109\) & \(-0.0071\) & \(-0.0096\) \\ \cline{2-8}  & ear & \(0.056\) & \(0.446\) & \(-0.026\) & \(-0.0650\) & \(0.0134\) & \(0.0176\) \\ \cline{2-8}  & total & \(0.197\) & \(0.650\) & \(0.330\) & \(-0.0542\) & \(0.0063\) & \(0.0080\) \\ \hline \multirow{4}{*}{\(3\)} & body & \(-0.263\) & \(0.290\) & \(0.529\) & \(0.0491\) & \(-0.0101\) & \(0.0205\) \\ \cline{2-8}  & ear & \(-0.106\) & \(0.582\) & \(-0.215\) & \(-0.1065\) & \(0.0259\) & \(0.0435\) \\ \cline{2-8}  & total & \(-0.368\) & \(0.872\) & \(0.314\) & \(-0.0574\) & \(0.0158\) & \(0.0639\) \\ \hline \multirow{4}{*}{\(4\)} & body & \(0.157\) & \(0.186\) & \(0.415\) & \(0.0315\) & \(-0.0350\) & \(-0.0078\) \\ \cline{2-8}  & ear & \(0.062\) & \(0.420\) & \(-0.050\) & \(-0.0638\) & \(0.0165\) & \(0.0197\) \\ \cline{2-8}  & total & \(0.219\) & \(0.606\) & \(0.365\) & \(-0.0322\) & \(-0.0183\) & \(0.0120\) \\ \hline \multirow{2}{*}{\(5\)} & body & \(-0.195\) & \(0.836\) & \(0.640\) & \(-0.0446\) & \(0.0007\) & \(0.0540\) \\ \cline{2-8}  & body & \(0.193\) & \(0.687\) & \(0.545\) & \(-0.0286\) & \(-0.0069\) & \(-0.0143\) \\ \hline \end{tabular} Note: (1) The moment reference point is the origin of the digital-analog coordinate system; (2) All moments and lateral forces were calculated with a half model to represent the stress of parts (ears) accurately.  
\end{table} 
Table 2: Force and moment coefficients for the three grids used in the convergence study. Figure 5: The time averaged results along the centerline of square cylinder flow [24]. Because some common characteristics were present in the flow field of the three configurations, we mainly analyzed the aerodynamic characteristics under the two conditions of configuration 1. We only described the conclusions for configurations 2 and 3. Figures 6-11 show the pressure distribution and streamlines on the surface of the device, as well as the off-surface streamlines around the device under different working conditions. An evident high-pressure zone appeared on the windward side because the blockage effect of the device reduced the flow velocity; additionally, the low-pressure belt at the shoulder was induced by the flow acceleration when it bypassed the large-curved corner, and a reverse pressure gradient was formed because of the intense flow acceleration and the relatively higher pressure downstream of the shoulders. Then, the flow separated near the shoulders, forming a recirculation zone on the leeward side.