1.3.3 Explosively loaded cylindrical panel

Products: ABAQUS/Standard  ABAQUS/Explicit  

A cylindrical shell panel, firmly clamped on all four sides, is exposed to the detonation of a high explosive layer. The problem illustrates the use of initial velocity conditions to model sudden, impulsive loadings arising from the detonation. In the course of the analysis a strong plastic hinge forms along the edge of the detonation area. Both experimental and numerical results for this problem have been reported by Leech (1966) and Morino et al. (1971).

Problem description

Controls and tolerances

For the ABAQUS/Standard analysis we choose to set the time integration accuracy control parameter (HAFTOL) to a very large (essentially infinite) value. This implies that we are choosing automatic control for the time stepping, but we are not controlling the accuracy of the time integration. The time increments will be limited only by the ability of the Newton scheme to solve the nonlinear equilibrium equations. This is a common technique for obtaining low-cost solutions for highly dissipative, strongly nonlinear cases. It is effective because the nonlinearities limit the time increments, and the high level of dissipation quickly removes the high frequency content from the solution. In practice it is desirable to verify the results with a second, more expensive, analysis in which a realistic value of HAFTOL is used. Default controls are used in ABAQUS/Explicit.

Results and discussion

Input files

References

Table

Table 1.3.3–1 Maximum deflection along center line of the panel at y=159.5 mm (6.28 in).

CodeElement TypeMesh SizePOISSONOFFSETMaximum Deflection
 
mmin
ABAQUS/StandardS48 × 160028.701.13
ABAQUS/StandardS48 × 160.5027.431.08
ABAQUS/StandardS4R8 × 160028.961.14
ABAQUS/StandardS4R8 × 160.5027.691.09
ABAQUS/StandardS4R58 × 160.5030.481.20
ABAQUS/StandardS3R8 × 160.5031.241.23
ABAQUS/StandardS8R4 × 80.5031.241.23
ABAQUS/StandardS8R54 × 80.5031.241.23
ABAQUS/StandardS9R54 × 80.5031.491.24
ABAQUS/StandardSTRI654 × 80.5031.491.24
ABAQUS/ExplicitS4R8 × 32026.241.033
ABAQUS/ExplicitS4R16 × 32030.811.213
ABAQUS/ExplicitS4R(enhanced hourglass) 16 × 32030.711.209
ABAQUS/ExplicitS4R32 × 64030.861.215
ABAQUS/ExplicitS4R32 × 640.529.841.175
ABAQUS/ExplicitS4RS32 × 64031.111.225
ABAQUS/ExplicitS4RS32 × 640.529.191.149
ABAQUS/ExplicitS4RSW32 × 64031.211.229
ABAQUS/ExplicitS4RSW32 × 640.529.291.153
Experimental31.751.250


Figures

Figure 1.3.3–1 S4R5 and S9R5 deformed configurations at 400 s (ABAQUS/Standard).

Figure 1.3.3–2 Deformed configurations for the 8 × 32, 16 × 32, and 32 × 64 meshes after 400 s (ABAQUS/Explicit).