Accession Number : AD0671931

Title :   A POINT EXPLOSION IN A COLD EXPONENTIAL ATMOSPHERE,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE FLUID MECHANICS LAB

Personal Author(s) : Laumbach,Dallas D. ; Probstein,Ronald F.

Report Date : MAY 1968

Pagination or Media Count : 52

Abstract : The problem considered is that of a strong shock propagating from a point energy source into a cold atmosphere whose density varies exponentially with altitude. An explicit analytic solution is obtained by taking the flow field as 'locally radial' and using an integral method with an energy constraint. A scaling law is given which eliminates the parametric dependence of the solution on the explosion energy, scale height, and atmospheric density at the point of the explosion. The scaling law also transforms the infinity of solutions for various polar angles into two distinct solutions which show that all motions of the ascending portion of the shock may be scaled from the vertically upward behavior and all motions of the descending portion of the shock may be scaled from the vertically downward behavior. The limit in the lateral direction of both of the fundamental solutions corresponds to the case of the uniform density atmosphere. Comparison with finite difference calculations shows excellent agreement. The empirical concept of 'modified Sachs scaling' for calculating the overpressure is considered and shown within this model to have a justification in the downward direction but a limited range of applicability in the upward direction. (Author)

Descriptors :   (*NUCLEAR EXPLOSIONS, HIGH ALTITUDE), PROPAGATION, SHOCK WAVES, ATMOSPHERES, ENERGY, SOURCES, DENSITY, MATHEMATICAL MODELS, PRESSURE, INTEGRALS, VELOCITY, MATHEMATICAL ANALYSIS, BLAST

Subject Categories : Explosions

Distribution Statement : APPROVED FOR PUBLIC RELEASE