An Experimental Study of the Reverse Percolation Lofting Process in a Sand Medium.

摘要

A vertical shock tube was used to approximate the time dependent overpressure at 1km from a nominal 1Mt source,in order to study the lofting response of a porous sand medium,arising from the gas flow into and out of the medium. The basic shock wave form applied to the sand surface in the vertical shock tube,had a peak value of 100psig,and a positive duration of approximately 0.75seconds. The corresponding Brode function has an estimated positive duration of 1.1sec,but was closely approximated by the experimental shock over the first 0.4microseconds. (Modified author abstract)