Thermal Convective Flow Registration by Laser Beams Spatial Characteristics Analysis

The paper proposes a laser fiber-optic system for early fire detection based on measurement and correlation analysis of the spatial characteristics of laser beams during the interaction with a thermal convective flow. The principle of its operation is based on the analysis of spatial characteristics of a laser beam during interaction with a thermal convective flow. A laboratory bench for measuring the spatial characteristics of laser beams with the possibility to change the type of optical fiber was implemented. Experimental studies of measuring the spatial characteristics of beams from a single-mode and multi-mode fiber during the interaction with a thermal convective flow are carried out. A processing technique based on the calculation of cross-correlation functions of samples of spatial distributions of laser beams is proposed, and the results of their computer processing are presented.