Shock Initiation of LX-17 as a Function of Its Initial Temperature.

摘要

The TATB-based pressed solid explosive LX-17 has been demonstrated to exhibit significant differences in shock sensitivity as its initial temperature is varied from (minus)54(degree)C to +88(degree)C. In this combined experimental-computational study, embedded gauges were used to measure the particle velocity and pressure histories in reacting LX-17 at various initial shock pressures and time durations at three initial temperatures: cold ((minus)54(degree)C), ambient (25(degree)C), and hot (88(degree)C). The ignition and growth reactive flow computer model, which had previously been normalized to a great deal of embedded gauge and other shock initiation data for ambient temperature LX-17, was then used to determine the differences in chemical reaction rates which are required to calculate the cold and hot LX-17 data. The embedded gauge records clearly demonstrate that during shock compression at colder temperature there are fewer ignition hot spots and that the growth of reaction rates from these hot spots is also slower. At higher temperatures the ignition is more vigorous and the growth of reaction rates is also faster. However, the transition to detonation occurs as rapidly in cold LX-17 as it does in ambient or hot LX-17. The changes in the three reaction rate terms of the ignition and growth model necessary for accurate simulations are consistent with these experimental observations. 34 refs., 15 figs., 1 tab.