Study of liquid-solid phase interface method of explosives based on distributed fiber optic sensors

Abstract

To discover and understand the solidification characteristics of energetic materials in the melting and casting process, the distributed optical fiber based on back Rayleigh Scattering was embedded in TNT/Octogen-based melting and casting explosives to monitor the solidification process from the liquid phase, to finally achieve realtime online monitoring of the strain of melt-casting during curing. The method of implanting the strain sensing optical fiber is to fix the optical fiber at the position in contact with the mold according to a predetermined path, fix the temperature sensing optical fiber in the center of the mold from top to bottom, and record the change of the center wavelength Rayleigh Scattering during the curing process, then converted into a stress index. The solid-liquid phase transition interface identification method based on an optical fiber sensor and proposed here, allows direct determination without decoupling from the temperature field. Therefore, the method of implanted distributed optical fiber sensing can monitor the solidification process of molten-cast explosives, which provides an effective and reliable method for more detailed and comprehensive analysis and monitoring of the solidification characteristics of energetic materials.