为了探索激光吸收光谱技术在非均匀流场中的应用, 提出了一种新的实现非均匀流场中气体参数定量测量的方法。 预知被测流场中的温度变化范围后, 选择在该温度范围内具有近似线性变化特性的谱线, 线性拟合该温度范围内的谱线强度, 结合实验测量的吸收光谱便可以实现非均匀流场中H2O组分权重的温度积分平均值和H2O组分积分平均值的定量测量。 两温度分布和高斯温度分布模型的仿真研究证明了该方法的有效性和可靠性。 两温度分布模型中的测量结果与理论值的偏差分别小于082%和110%, 而高斯温度分布模型中不同光线中的测量值与理论值的最大偏差分别小于09%和36%。

In order to explore the application of laser absorption spectroscopy in the non-uniform flow, a new strategy that provides quantitative measurements of gas parameters in non-uniform environments are put forward. After evaluating the range of temperature in the field and choosing the appropriate transitions whose strengths that scale linearly with temperature, the H2O mole-fraction-weighted path-average temperature and geometric path-average H2O mole fraction can be quantitatively measured. The simulated results from two-temperature and Gaussian-temperature distribution model show the availability and reliability of this method. Compared with theoretical value, the relative errors of measured results in the two-temperature distribution model are 082% and 110% while the most relative errors in the Gaussian-temperature distribution model are 09% and 36%.