Three-dimensional Temperature Field Measurement Method and Application Based on Improved Multiplicative Regularization Reconstruction Algorithm

The accurate characterization of three-dimensional temperature fields is of great significance in aerospace and other fields. This paper proposes a three-dimensional temperature field measurement method based on an improved multiplicative regularization reconstruction algorithm. To address the challenge of selecting regularization parameters in regularization algorithms, the multiplicative regularization algorithm with self-adaptive parameter adjustment is developed. Based on Dual-wavelength thermometry principles and leveraging the multi-channel imaging advantages of color cameras, a temperature measurement system is designed, incorporating dual or quad color cameras, bandpass filter elements, and synchronous triggering devices. Additionally, a sub-pixel-level matching method for dual-band image registration in four optical paths is developed, which greatly simplifies the measurement setup while ensuring reconstruction accuracy. Validation experiments demonstrate the feasibility of the proposed method, achieving the three-dimensional temperature field reconstruction and evolution analysis of solid propellant combustion flames.