DEVELOPMENT OF AN EULERIAN FINITE ELEMENT CODE

CURRENT NUMERICAL COMPUTATIONS TO DESCRIBE NUCLEAR GROUND SHOCK ENVIRONMENTS, NUCLEAR CRATER FORMATION, IMPACT DYNAMICS AND PENETRATION MECHANISMS PRESENTLY EMPLOY EULERIAN-BASED FINITE DIFFERENCE CODES BECAUSE OF THEIR ABILITY TO MODEL THE MASS FLUX PHENOMENA IN TRACKING MATERIAL MOVEMENT THROUGH THE DISCRETIZED SPACE. THE FINITE DIFFERENCE CODES SUFFER IN COMPARISON TO FINITE ELEMENT CODES, HOWEVER, IN THEIR ABILITY TO TREAT IRREGULAR GEOMETRIES AND VARIATIONS IN BOTH MESH SIZE AND ELEMENT SHAPE. BUT, BECAUSE FINITE ELEMENT CODES ARE LAGRANGIAN-BASED, MODELING OF MASS FLOW IS EXCEEDINGLY DIFFICULT AND IS NOT PRESENTLY PRACTICED. THIS PROBLEM CAN BE OVERCOME BY ELIMINATING THE INABILITY OF FINITE ELEMENT CODES TO ACCOMMODATE MASS FLUX PHENOMENA.