RADIAL_DEFORMATION
Solution control and techniques
"Optional title"
coid
entype, enid, $t_{beg}$, $t_{end}$
Parameter definition
Description
With this command active, the outer surface of an object is only allowed to undergo a uniform radial deformation. It is typically used to stabilize the initial spherical expansion of explosive charges in UNDEX simulations.
Example
Enforcing a radial expansion of an UNDEX charge
In UNDEX simulations, it is recommended to model the detonating explosive with Finite Elements rather than with CFD. The early interaction between explosive and and water (Surface SPH) is more accurate with a Lagrangian FE-SPH contact than with the CFD-SPH coupling.
However, small Finite Elements might distort when interacting with large and heavy SPH nodes. By enforcing a homogeneous radial deformation of the expanding detonation products, these effects can be avoided.
Beyond the initial rapid radial expansion phase, the bubble dynamics is better handled with a CFD approach. In this example, the explosive elements are deactivated after $1ms$ and their state is mapped to the CFD domain (E2C).
