Simulation Development for Silo Test Program (STP). Volume 1. Design and Evaluation of a Variable HEST (High Explosive Simulation Technique) for STP 3.5A Experiment
Abstract:
In support of the Defense Nuclear Agency DNA Silo Test Program STP, we designed and evaluated the performance of a variable high explosive simulation technique HEST to simulate the airblast environment resulting from a 1.95-kt 18-scale of 1 MT nuclear surface burst over a pressure range of 500 MPa 5 kbar to 7 MPa 1000 psi. Our final design consisted of a variable HEST in which Iremite-60 explosive is used predominantly in the pressure range from 500 to 100 MPa, and 0.085 kgm 400 grainft primacord explosive is used in the pressure range from 100 to 7 MPa. The overburden height increases linearly with range from 0.64 to 1.15m. The cavity height increases linearly with the range from 38 mm to the 500-MPa location to 70 mm at the 35-MPa location. Beyond this point, the cavity height remains constant at 70 mm. The above HEST simulator was used in the STP 3.5A experiment performed by WES at Fort Knox. On the basis of photopole, airblast, and near surface soil stress gage data, the impulse from the HEST agreed, to within measurement error, with the design goals for both short 10 ms and long 90 ms time frames. Hence, the full positive phase of a 1.95-kt surface burst was successfully simulated by the HEST.