Inverse method investigation of thermal radiation property of liquid hydrocarbon fuel

The spectral transmittance radio calculation model of glass- liquid hydrocarbon fuel-glass three layer slabs was developed based on ray trace method, and an inverse model was built to determine the thermal radiation property (k is extinction coefficient and n is refractive index) of liquid hydrocarbon fuel in the three layer slabs. The inverse model was retrieved, and was combined with Monte-Carlo method and area approach method. The thermal radiation property of heptane attained in the references was selected as the true values, and the spectral transmittance radio of the three layer slabs based on the direct model simulation was regarded as the experimental values. The thermal radiation property of Heptane was achieved by the inverse model, and then the effect of measurement error on the inverse results was also investigated. The results show that, (1) the standard deviation of k calculation error by the inverse model is less than 0.003%, and that of n is higher than 21%. (2) the effect of measurement error on the inverse results is urgent distinct, and some inversed calculation values are obviously when the measurement error is higher than 1%. (3) the standard deviation of k calculation error and measurement error y satisfy the equation which is y=2285.2 γ ²-10.484γ+0.0037. The effect of measurement error on the standard deviation of n calculation error is lower, however, the n calculation error is higher than 20% when the measurement error exists.