激波风洞超燃冲压发动机推阻测量技术  

Thrust/Drag measurement techniques of a free flight scramjet in a shock tunnel

作　　者：陈勇富 卢洪波[1] 文帅[1] 陈星[1] 孙日明[1] CHEN Yongfu;LU Hongbo;WEN Shuai;CHEN Xing;SUN Riming(China Academy of Aerospace Aerodynamics,Beijing 100074,China)

机构地区：[1]中国航天空气动力技术研究院,北京100074

出　　处：《空气动力学学报》2022年第1期141-148,共8页Acta Aerodynamica Sinica

基　　金：国家重点研发计划资助项目(2019YFA0405200)。

摘　　要：面向高马赫数超燃冲压发动机推阻性能测量需求,基于FD-21高焓激波风洞,建立了基于自由飞原理的发动机模型推阻测量技术,创新引用了电永磁铁悬挂释放技术与高精度时序控制技术。设计了梯形多孔圆形阵列标记板,使用基于圆形特征阵列标记与图像识别技术的模型典型特征追踪方法,并对位移原始数据进行最近邻离群点剔除,用二阶中心差分求取模型加速度并进行傅里叶频谱分析,通过巴特沃斯低通滤波方法去除微分运算引入的高频噪声。进行了发动机模型自由落体运动试验和通流试验,探讨了自由飞测力技术的数据处理方法,获得了发动机模型的受力数据,给出了测量技术的精准度。在自由落体运动试验中,获得的加速度与当地标准重力加速度值偏差约为±2%。在FD-21风洞名义马赫数10模拟条件下进行了两次冲压发动机通流试验,获得的水平方向加速度相对偏差为2.32%,竖直方向加速度的相对偏差为7.44%。To investigate the performance of a Mach 8 scramjet,a free flight force measurement technique was developed in a high-enthalpy free piston driven shock tunnel FD-21.A nonlinear motion track method integrating the circular feature markers and image recognition was proposed.The scramjet model was suspended and released by a novel electric permanent magnet which controls the model accurately.A high-precision sequence control system was adopted to implement the time synchronization.To facilitate the tracking of the scramjet model,a trapezoidal porous circular array marker plate was designed and mounted on the outward surface of the model.The lamp-house illumination method was employed in the backlight system,in which the maximum power of the photosource is up to 300 W and the average brightness can reach 45000 Lux at one meter working distance.Based on the characteristics of circular array,a typical model tracking method using the image recognition technique was studied.An outlier elimination of the original displacement data was implemented using the nearest neighborhood algorithm.The noise-free acceleration was subsequently obtained by the second derivative of the filtered displacement.Data processing methods including the motion displacement extraction were discussed by two types of experiments involving a free-falling scramjet in the quiescent air and a free-flight scramjet without fuel injection at Mach 10.The force data of the engine model was obtained,and the precision of measurement technology was discussed.For the former,the measured gravity acceleration is consistent with the local true value with a deviation of only ±2%.For the latter,there exhibits a good repeatability with a deviation of 2.32% for the horizontal acceleration and 7.44% for the vertical acceleration.In the future research plan,the protection device of the electric permanent magnet will be further optimized.In addition,more measurement methods,such as triaxial accelerometers and stress wave balances,will be used to realize cross validation

关 键 词：高焓激波风洞 超燃冲压发动机 推阻测量技术 自由飞 图像识别 

分 类 号：V211.751[航空宇航科学与技术—航空宇航推进理论与工程]