A data processing method for two-Color pyrometers in accurate temperature measurement of high-temperature flow fields

To achieve precise temperature measurement of two-dimensional high-temperature flow fields, a data processing method for two-color pyrometers was designed based on the graybody hypothesis. Initially, the two channels of the designed pyrometer underwent calibration to establish monochromatic pyrometers. Subsequently, temperature and emissivity were computed by globally minimizing the difference between the two-color and monochromatic temperatures. Finally, the deviations between two-color and monochromatic temperatures were presented. Moreover, an improved sensitivity coefficient correction method is proposed. An electromagnetic emission simulation device was employed for experimentation. From 2200 K to 3300 K, the deviation between monochromatic and two-color temperatures is 3.3 % to 6.4 %, primarily due to the pyrometer uncertainty. The graybody hypothesis is applicable to Tests 1 and 2 because the monochromatic temperature deviations are within 2.2 % and the emissivity ratios are close to 1. However, Test 3 is the initial stage of projectile launch, the emissivity model is revised to lambda- 0.5 .