Investigation of shock waves in explosive blasts using fibre optic pressure sensors

We describe miniature all-optical pressure sensors, fabricated by wafer etching techniques, less than 1 mm 2 in overall cross-section with rise times in the µs regime and pressure ranges typically 900 kPa (9 bar). Their performance is suitable for experimental studies of the pressure–time history for test models exposed to shocks initiated by an explosive charge. The small size and fast response of the sensors promises higher quality data than has been previously available from conventional electrical sensors, with potential improvements to numerical models of blast effects. Results from blast tests are presented in which up to six sensors were multiplexed, embedded within test models in a range of orientations relative to the shock front.