is a set of
fast running algorithms which simulate the penetration of and
damage to spaced target structures by compact and non-compact
warhead fragments and long rods at speeds up to 5 km/sec. The
model predicts penetrator mass loss, velocity loss, trajectory
change, and tumbling throughout a target. The mass loss model
includes an impact fracture model that, depending on impact
conditions, transforms an incident intact warhead fragment
into an expanding, multi-particle debris cloud which FATEPEN
then tracks through the remaining target structure. FATEPEN
also predicts multi-particle loading and damage to plate
structures.
The FATEPEN model is based as much as possible
on fundamental principles of mechanics together with
assumptions regarding the principal loading and response
mechanisms involved. The latter derive directly from
experimental observation. Empirical elements have been
introduced either to obtain better agreement with available
test data or to describe phenomena not readily amenable to
first principle analytical modeling.
The penetration algorithms are comprised of
deterministic, analytical/empirical engineering models and are
contained in a separate Dynamic Link Library for easy
portability to other calling programs. A Visual Basic,
Graphical User Interface is used to define and/or select
penetrators, targets, and encounter conditions in the stand
alone PC version of the code.
The FATEPEN algorithms have been partially
validated by comparisons between model predictions and test
results for a variety of projectile and target combinations.
The primary application of the code has been
target vulnerability and weapon lethality assessments
involving air targets and lightly-armored surface targets.
FATEPEN has been transitioned to use by all three Services and
is used as a submodel in a number of simulations, including
the Advanced Joint Effectiveness Model (AJEM).
The government proponent for FATEPEN is now
the Joint Technical Coordinating Group for Munitions
Effectiveness (JTCG/ME). The model was developed over the past
20 years for the Naval Surface Warfare Center, Dahlgren
Division (NSWC/DD).
Required FATEPEN penetrator input includes penetrator
material, hardness, shape, weight, dimensions, and initial
velocity and orientation. Additional material properties and
inertial parameters are computed or assigned by FATEPEN.
