吸收光谱法冲压发动机隔离段来流质量的流量测量

为实现冲压发动机地面直连试验中来流质量流量的测量校核,研制了吸收光谱法测量系统并开展了台架验证试验。首先,介绍了基于隔离段温度、流速测量计算质量流量的原理,针对台架试验环境适应性、长期工作稳定性问题,介绍了测量系统和光机设计方案,然后介绍了波长标定、温度与流速反演关键算法。在Ma6.5,6.0kg/s流量状态两个独立车次台架试验吸收光谱法计算质量流量的最大偏差为5%,验证了所提出方法的可行性。该方法为吸气式发动机来流状态的精细测量提供了新的方案和技术手段,未来可望用于来流捕获的实时反馈控制。

Measurement of flow flux for scramjet isolator inflow based on absorption spectroscopy

To realize online inflow mass flux validation during ground testing of a direct-connect scramjet facility, an absorption-spectroscopy-based system was developed and tested. First, a mass flux calculation method based on temperature and flow velocity measurements in the isolator section was presented. Taking into account environmental adaptability in vehicle testing and the system's long-term stability, miniaturized system and optomechanical design strategies were presented. Then, key algorithms, such as relative wavelength calibration, flow temperature, and velocity retrieval were described. Two independent vehicle tests with inflow states of Ma6.5 and 6.0 kg/s were carried out, and the results show that the maximum deviation in the tunable diode laser absorption spectroscopy results is 5%, validating the feasibility of the method. This research provides a new solution and tool for the delicate measurement of flow state with the potential to feed back the control inflow capture process.