Fiber Bragg sensing of high explosive detonation experiments at Los Alamos National Laboratory

An all optical-fiber-based approach to measuring high explosive detonation front position and velocity is demonstrated. By measuring total light return using an incoherent light source reflected from a fiber Bragg grating sensor in contact with the explosive, dynamic mapping of the detonation front position and velocity versus time is obtained. We demonstrate two examples of detonation front measurements: PETN detasheet test and detonation along a multi-HE cylindrical rate stick containing sections of PBX 9501, Comp B, TNT, PBX 9407, PBX 9520, and inert PMMA. In the PETN detasheet measurement, excellent agreement with complementary diagnostics (electrical pins) is achieved, with accuracy in the detonation front velocity at the 0.13% level when compared to the results from the pin data.