Small Scale Shock Tube Experiments Using a Computer Controlled Active Rarefaction Wave Eliminator.

摘要

The technology needed to construct a facility for testing full scale military equipment, termed the Large Blast/Thermal Simulator (LB/TS), is under development. One of the major components of the proposed facility will be a large valve controlling the flow exiting the downstream end, called a rarefaction wave eliminator (RWE). An active RWE, one which adapts its open area to changing flow conditions, will be used in the LB/Ts. Using an active RWE allows a relatively short facility to produce the same range of blast simulations that would otherwise require a very long expansion section. A small scale active rarefaction wave eliminator was constructed and tested through a series of blast conditions. Shock overpressures ranged from 40 - 100 kPa, while positive phase durations were in range of 14 - 54 ms. Pressure histories and impulse values obtained from tests using the RWE compared well with long expansion section baseline data. The results of this program show that an active rarefaction wave eliminator can be used in place of a long expansion section to achieve successful nuclear blast simulation. Knowledge gained from the use of this RWE will be employed during construction and testing of the 1:6 scale and full scale active RWE's. (jhd)