SOLUTION APPROXIMATION FOR LAGRANGIAN BALLISTIC PROBLEM

A.V. Zabrodin, N.N. Chentsov
VANT. Ser.: Mat. Mod. Fiz. Rroc 1990. Вып.3. С. 15-17.

      A classical problem of two flying-away flat pistons separated with a volume of highly-compressed ideal gas with γ isentrope index is under consideration. Approximated formulas to find final energy of light pistons and gas velocity distribution as functions of Eulerian and Lagrangian coordinates are suggested; their relation with Sedov similarity solutions for flat cylindrical and spherical flows is shown. Computational difficulties for the ballistic problem with difference methods at γ ≈ 1 are analyzed; the volume of the model is estimated from below.

      The explosive in the problem under consideration is initiated by the contact with the impactor that flies at a constant velocity. Specific features of the on-going processes are reproduced in the numerical experiment. A formula for approximated estimation from above of the velocity of piston flying that gives good agreement with computational data is produced.