## 6 Verification Test of Parameter Influence  
As shown in Figure 14 and Table 12, the influence of the inflection angle on support interference was significant. In addition, the inflection angle was the most important geometric parameter of the V-shaped support (it would become the conventional straight sting support when the inflection angle is 0\({}^{\circ}\)). With the consideration of the stiffness limit, the dummy V-shaped supports with different inflection angles (P = 13\({}^{\circ}\)/15\({}^{\circ}\)/17\({}^{\circ}\), as shown in Figure 15) were designed and manufactured to conduct verification tests of support interference.  
A verification test of support interference was conducted in the 2.4 m \(\times\) 2.4 m transonic wind tunnel of the CARDC. The test model of the BWB aircraft was consistent with the numerical simulation, which was installed in the wind tunnel by blade support (Figure 15b). The dummy V-shaped support was installed on the rear strut and extended into the model cavity (test model is not shown in Figure 15b, and the relative relationship can be found in Figure 2). As the movement of the whole test system was  
Figure 14: Sensitivity comparison of \(\Delta C_{m}\) with different geometric parameters (\(Ma=0.75\), \(\alpha=0^{\circ}\)).  
Figure 15: Verification test equipment of the dummy V-shaped support with different inflection angles (P = 13\({}^{\circ}\)/15\({}^{\circ}\)/17\({}^{\circ}\)) and different straight-section diameters (D = 52 mm/44 mm): (**a**) dummy V-shaped supports with different inflection angles; (**b**) verification equipment in the wind tunnel; (**c**) straight section of the dummy V-shaped support with D = 52 mm, before the mechanical cutting; (**d**) straight section of dummy V-shaped support with D = 44 mm, after the mechanical cutting.  
synchronous, the collision or transmission of force between the dummy support and test model was avoided. The interference of real V-shaped support on the BWB aircraft was simulated by this method in a high-speed wind tunnel. The verification results of support interference with different inflection angles is shown in Figure 16. Finally, the straight-section diameter of the dummy V-shaped support was cut from 52 mm to 44 mm (as shown in Figure 15c,d), so that the verification test of parameter D could be conducted. The results are shown in Figure 17.  
In Figure 16, the pitching moment interference of the BWB aircraft decreased as the inflection angle increased, and the difference of drag interference was quite small, which was in good agreement with the numerical results in Figure 12. Similarly, the changing tendency of \(\Delta C_{m}\) and \(\Delta C_{D}\) with different parameters of D was basically the same in Figures 7 and 17. The real test equipment, such as blade and strut, were not simulated in the numerical calculation so that the tiny difference between the CFD and EFD was acceptable. The comparison indicated that interference results of the V-shaped support with different geometric parameters in the current research are effective and reliable.  
Figure 16: Support interference test results of the BWB aircraft with different inflection angles (P = 13\({}^{\circ}\)/15\({}^{\circ}\)/17\({}^{\circ}\), \(Ma\) = 0.75): (**a**) \(\Delta C_{D}\)-\(\alpha\) curves; (**b**) \(\Delta C_{m}\)-\(\alpha\) curves.  
Figure 17: Support interference test results of the BWB aircraft with different straight-section diameters (D = 44 mm/52 mm, \(Ma\) = 0.75): (**a**) \(\Delta C_{D}\)-\(\alpha\) curves; (**b**) \(\Delta C_{m}\)-\(\alpha\) curves.