Impulse Plug Measurements of Blast Reflected Impulse at Close Range

摘要

A series of blast tests is described in which blast impulse is measured by an impulse plug technique for spherical explosive charges. In this approach the reflected blast impulse delivered to a hardened bullet-shaped steel plug is determined from a measurement of the plug terminal momentum. Plug velocity is measured by a high-speed, high-resolution video camera operating at 20,000 frames per second. Spherical C4 charges are studied for varying charge weight and charge-to-plug standoff distance. Tested standoffs include the demanding near-field blast zone within which pressure measurement by transducer is ex- tremely difficult or impossible. Results are compared with previous studies made using transducer and impulse plug methods for both C4 and Pentolite charges. The present data for half-pound C4 charges are in good agreement witrtmuch earlier impulse plug data for spherical Pentolite in the near-field region, however, differences of up to 26% are noted with more recent transducer measurements for C4 just beyond the near-field zone. Test results are also compared with hydro-code simulations of the plug response.