Scanning Electron Beam Thermal Assessment Based on Actual Trajectory Modeling

Scanning electron beam thermal assessment (SEBTA) is an innovative pretest technology for wind tunnel experiments. The initial non-jumping-process SEBTA method (SEBTA-NJP) considered and regulated only the dwell duration of the electron beam at the scanning points to achieve heat flux field reconstruction, failing to accurately capture the actual scanning trajectory and leading to suboptimal reconstruction accuracy. To enhance the accuracy of the experiments, based on a calibration method for key parameters in the closed-loop digital-to-analog conversion process that can enable the precise calculation of the electron beam’s jump process, we develop a jumping-process SEBTA method (SEBTA-JP), enabling the precise characterization of the actual scanning trajectory. For a uniform heat flux field of [Formula: see text], SEBTA-JP achieved maximum and average absolute values of the reconstruction deviations of 19.00% and 3.63%, respectively, representing reductions of 24.00% and 26.81%, respectively, compared to SEBTA-NJP. For a Gaussian-distributed heat flux field with a peak of [Formula: see text], SEBTA-JP achieved maximum and average absolute values of the reconstruction deviations of 18.90% and 5.04%, respectively, corresponding to reductions of 37.83% and 26.53%, respectively, compared to SEBTA-NJP. This study provides an accurate test environment for thermal protection materials and structures.