基于激光吸收光谱技术的超声速气流参数测量

采用可调谐半导体激光吸收光谱(TDLAS)技术,针对超声速直连台隔离段内超声速气流温度、组分浓度、速度和质量流量进行了测量.选择H2O的两条吸收谱线7 185.597 cm-1和7 454.445 cm-1,采用直接吸收-分时扫描方式,测量流场静温为899 K,并结合吸收面积得到H2O的组分浓度20.7%.根据安装在流场上游和下游成60的两条光路,测量流场速度为1 205 m/s,结合壁面压力传感器,测量流场的质量流量为1 500.49 g/s,较真实值偏差为5.23%.TDLAS测量系统实现了对超声速气流多参数快速线测量.

Measurement of supersonic flow parameters using laser absorption spectroscopy

Based on the tunable diode laser absorption spectroscopy(TDLAS) technique, temperature, concentration, velocity and mass flux of the supersonic flows were measured in isolator of a direct-connected scramjet. Two H2O absorption transitions 7 185.597 cm-1 and 7 454.445 cm-1 were adopted by using direct-absorption and Time Division Multiplexing strategy. The measurement results show the static temperature is of 899 K and the H2O concentration is of 20.7% calculating from the absorption area. A cross-beam configuration with angles of 60 along the flows was used to measure the axial velocity. Combined with the pressure sensor on the wall and the measured velocity of 1 205 m/s, the mass flux of the flow is of 1 500.49 g/s with deviation of 5.23%. The TDLAS measured system can be used for in-situ measurements of multiple parameters of supersonic flows.