基于彩色纹影的EdneyIV型激波相互作用研究

发展了一种高分辨率和灵敏度的彩色纹影技术，研究高超声速条件下EdneyIV型激波相互作用。解决了制作彩色滤光片的关键技术，采用特制的彩色滤光片代替了传统纹影系统中的刀口，高速彩色相机曝光时间60Vs，帧频6242fps。将光源限制在0．5mm×20mm的狭缝内以提高系统灵敏度。实验在马赫数为5的激波风洞内进行，EdneyIV型激波相互作用由15°斜劈和20mm直径钝头体产生，来流静压和静温分别为1800Pa和100K。数值模拟采用迎风格式求解三维RANS方程。实验得到了清晰的彩色纹影照片，细致地呈现了EdneyIV型激波相互作用的波系结构和马赫数为1．2的超声速射流。数值计算与实验结果很好地吻合，共同揭示了EdneyIV型激波相互作用机制和钝头体表面局部高压区域的形成原因。

Investigation of Edney IV shock wave interaction based on color schlieren

To investigate the Edney IV shock wave interaction in hypersonic flow, color schlieren with high resolution .and sensitivity was developed. Knife edge in traditional schlieren system was replaced by a special designed color filter in this system. High speed color camera with 60μs exposure time and 6242fps was used. To improve the sensitivity of the system, the light source was restricted by a rectangular slot with 0.5mm × 20mm. The experiment was per- formed in shock tunnel at Mach 5. Edney IV interaction was generated in hypersonic free stream by 15° edge and blunt body with diameter of 20mm. The static pressure and temperature of the flow were 1800Pa and 100K, respectively. Three dimensional RANS equations were solved with upwind format to simulate the interaction. Clear color schlieren photo was gotten, which de- tailedly exhibited the wave system structure of Edney IV interaction and the supersonic iet at Mach 1.2. The simulation results matched well with the experiment, revealing the mechanism of Edney IV shock wave reaction and the formation of the high pressure region on the blunt bodv.