<s>
MOOSE	B-Language
(	O
Multiphysics	B-Algorithm
Object	B-Language
Oriented	I-Language
Simulation	O
Environment	O
)	O
is	O
an	O
object-oriented	B-Language
C++	B-Language
finite	B-Application
element	I-Application
framework	O
for	O
the	O
development	O
of	O
tightly	O
coupled	O
multiphysics	B-Algorithm
solvers	O
from	O
Idaho	O
National	O
Laboratory	O
.	O
</s>
<s>
MOOSE	B-Language
makes	O
use	O
of	O
the	O
PETSc	B-Language
non-linear	O
solver	O
package	O
and	O
libmesh	O
to	O
provide	O
the	O
finite	B-Application
element	I-Application
discretization	B-Algorithm
.	O
</s>
<s>
A	O
key	O
design	O
aspect	O
of	O
MOOSE	B-Language
is	O
the	O
decomposition	O
of	O
weak	B-Algorithm
form	I-Algorithm
residual	B-Algorithm
equations	O
into	O
separate	O
terms	O
that	O
are	O
each	O
represented	O
by	O
compute	O
kernels	O
.	O
</s>
<s>
The	O
combination	O
of	O
these	O
kernels	O
into	O
complete	O
residuals	B-Algorithm
describing	O
the	O
problem	O
to	O
be	O
solved	O
is	O
performed	O
at	O
run	O
time	O
.	O
</s>
<s>
MOOSE	B-Language
comes	O
with	O
an	O
extensive	O
library	O
of	O
kernels	O
providing	O
residual	B-Algorithm
terms	O
for	O
solid	O
mechanics	O
,	O
Navier	O
–	O
Stokes	O
equations	O
,	O
phase	O
field	O
models	O
and	O
more	O
.	O
</s>
<s>
MOOSE	B-Language
uses	O
VTK	B-Language
.	O
</s>
<s>
The	O
development	O
of	O
MOOSE	B-Language
at	O
Idaho	O
National	O
Laboratory	O
(	O
INL	O
)	O
,	O
beginning	O
in	O
May	O
2008	O
,	O
has	O
resulted	O
in	O
a	O
unique	O
approach	O
to	O
computational	O
engineering	O
that	O
combines	O
computer	B-General_Concept
science	I-General_Concept
with	O
a	O
strong	O
underlying	O
mathematical	O
description	O
in	O
a	O
unique	O
way	O
that	O
allows	O
scientists	O
and	O
engineers	O
to	O
develop	O
engineering	O
simulation	O
tools	O
in	O
a	O
fraction	O
of	O
the	O
time	O
previously	O
required	O
.	O
</s>
<s>
The	O
heart	O
of	O
MOOSE	B-Language
is	O
the	O
Kernel	O
.	O
</s>
<s>
To	O
add	O
new	O
physics	O
to	O
an	O
application	O
built	O
using	O
MOOSE	B-Language
,	O
all	O
that	O
is	O
required	O
is	O
to	O
supply	O
a	O
new	O
Kernel	O
that	O
describes	O
the	O
discrete	O
form	O
of	O
the	O
equation	O
.	O
</s>
<s>
With	O
MOOSE	B-Language
,	O
only	O
the	O
Kernel	O
development	O
is	O
required	O
from	O
the	O
scientist	O
or	O
engineer	O
(	O
application	B-Application
developer	I-Application
)	O
.	O
</s>
<s>
MOOSE	B-Language
is	O
designed	O
to	O
do	O
everything	O
else	O
for	O
the	O
application	B-Application
developer	I-Application
,	O
such	O
as	O
finite	B-Application
element	I-Application
discretization	B-Algorithm
of	O
the	O
PDEs	O
,	O
the	O
nonlinear	O
solver	O
,	O
and	O
the	O
parallel	O
high	B-Architecture
performance	I-Architecture
computing	I-Architecture
.	O
</s>
<s>
The	O
idea	O
of	O
naming	O
MOOSE-based	O
applications	O
after	O
Idaho	O
indigenous	O
animal	O
species	O
is	O
loosely	O
based	O
on	O
Los	O
Alamos	O
National	O
Laboratory	O
's	O
1970s	O
–	O
1990s	O
approach	O
to	O
naming	O
their	O
codes	O
after	O
Native	O
American	O
tribes	O
and	O
artifacts	O
,	O
such	O
as	O
APACHE	O
,	O
CONCHAS	O
,	O
and	O
the	O
KIVA	B-Application
series	O
of	O
codes	O
.	O
</s>
<s>
There	O
are	O
now	O
over	O
twenty	O
MOOSE-based	O
application	O
animals	O
in	O
various	O
stages	O
of	O
development	O
,	O
ranging	O
from	O
recently	O
obtaining	O
preliminary	O
results	O
to	O
being	O
nationally	O
recognized	O
as	O
state-of-the-art	O
efforts	O
(	O
such	O
as	O
BISON	O
and	O
MARMOT	O
for	O
fuels	O
performance	O
modeling	O
&	O
simulation	O
activities	O
)	O
.	O
</s>
<s>
MOOSE	B-Language
is	O
a	O
development	O
and	O
run-time	B-Device
environment	I-Device
for	O
the	O
solution	O
of	O
multi-physics	B-Algorithm
systems	O
that	O
involve	O
multiple	O
physical	O
models	O
or	O
multiple	O
simultaneous	O
physical	O
phenomena	O
.	O
</s>
<s>
The	O
systems	O
are	O
generally	O
represented	O
(	O
modeled	O
)	O
as	O
a	O
system	O
of	O
fully	O
coupled	O
nonlinear	O
partial	O
differential	O
equation	O
systems	O
(	O
an	O
example	O
of	O
a	O
multi-physics	B-Algorithm
system	O
is	O
the	O
thermal	O
feedback	O
effect	O
upon	O
neutronics	O
cross-sections	O
where	O
the	O
cross-sections	O
are	O
a	O
function	O
of	O
the	O
heat	O
transfer	O
)	O
.	O
</s>
<s>
Inside	O
MOOSE	B-Language
,	O
the	O
Jacobian-Free	O
Newton	O
Krylov	O
(	O
JFNK	O
)	O
method	O
is	O
implemented	O
as	O
a	O
parallel	O
nonlinear	O
solver	O
that	O
naturally	O
supports	O
effective	O
coupling	O
between	O
physics	O
equation	O
systems	O
(	O
or	O
Kernels	O
)	O
.	O
</s>
<s>
The	O
physics	O
Kernels	O
are	O
designed	O
to	O
contribute	O
to	O
the	O
nonlinear	O
residual	B-Algorithm
,	O
which	O
is	O
then	O
minimized	O
inside	O
of	O
MOOSE	B-Language
.	O
</s>
<s>
MOOSE	B-Language
provides	O
a	O
comprehensive	O
set	O
of	O
finite	B-Application
element	I-Application
support	O
capabilities	O
(	O
libMesh	O
)	O
and	O
provides	O
for	O
mesh	O
adaptation	O
and	O
parallel	B-Operating_System
execution	I-Operating_System
.	O
</s>
<s>
The	O
framework	O
heavily	O
leverages	O
software	B-Library
libraries	I-Library
from	O
the	O
Department	O
of	O
Energy	O
(	O
DOE	O
)	O
and	O
the	O
National	O
Nuclear	O
Security	O
Administration	O
(	O
NNSA	O
)	O
,	O
such	O
as	O
the	O
nonlinear	O
solver	O
capabilities	O
in	O
either	O
the	O
Portable	B-Language
,	I-Language
Extensible	I-Language
Toolkit	I-Language
for	I-Language
Scientific	I-Language
Computation	I-Language
(	O
PETSc	B-Language
)	O
project	O
or	O
the	O
Trilinos	B-Language
project	O
.	O
</s>
<s>
BISON	O
was	O
the	O
first	O
MOOSE-based	O
application	O
"	O
animal	O
,	O
"	O
and	O
is	O
a	O
finite	O
element-based	O
nuclear	O
fuel	O
performance	O
code	O
applicable	O
to	O
a	O
variety	O
of	O
fuel	O
forms	O
including	O
light	O
water	O
reactor	O
fuel	O
rods	O
,	O
TRISO	O
fuel	O
particles	O
,	O
and	O
metallic	O
rod	O
and	O
plate	O
fuel	O
.	O
</s>
<s>
BISON	O
is	O
based	O
on	O
the	O
MOOSE	B-Language
framework	O
and	O
can	O
therefore	O
efficiently	O
solve	O
problems	O
on	O
either	O
two-dimensional	O
axisymmetric	O
or	O
three-dimensional	O
geometries	O
using	O
standard	O
workstations	O
or	O
large	O
high	B-Architecture
performance	I-Architecture
computers	I-Architecture
.	O
</s>
<s>
BISON	O
is	O
also	O
coupled	O
to	O
a	O
MOOSE-based	O
mesoscale	O
phase	O
field	O
material	O
property	O
simulation	O
capability	O
.	O
</s>
<s>
MARMOT	O
predicts	O
the	O
effect	O
of	O
radiation	O
damage	O
on	O
microstructure	O
evolution	O
,	O
including	O
void	O
nucleation	B-Algorithm
and	O
growth	O
,	O
bubble	O
growth	O
,	O
grain	O
boundary	O
migration	O
,	O
and	O
gas	O
diffusion	O
and	O
segregation	O
.	O
</s>
<s>
FALCON	O
eliminates	O
the	O
need	O
for	O
using	O
operator	O
splitting	O
methods	O
to	O
simulate	O
these	O
systems	O
,	O
and	O
the	O
scalability	O
of	O
MOOSE	B-Language
supported	O
applications	O
allows	O
for	O
simulating	O
these	O
tightly	O
coupled	O
processes	O
at	O
the	O
reservoir	O
scale	O
,	O
allowing	O
for	O
examination	O
of	O
the	O
system	O
as	O
a	O
whole	O
(	O
something	O
the	O
operator	O
splitting	O
methodologies	O
generally	O
cannot	O
do	O
)	O
.	O
</s>
<s>
RELAP-7	O
is	O
the	O
next-generation	O
tool	O
in	O
the	O
RELAP	B-Application
safety/systems	I-Application
analysis	I-Application
application	I-Application
series	I-Application
and	O
is	O
based	O
upon	O
the	O
MOOSE	B-Language
development	O
and	O
runtime	B-Device
environment	I-Device
framework	O
.	O
</s>
<s>
RELAP-7	O
will	O
retain	O
and	O
improve	O
the	O
basic	O
analysis	O
capability	O
of	O
RELAP5	B-Application
.	O
</s>
<s>
The	O
four	O
major	O
improvements	O
are	O
1	O
)	O
A	O
well-posed	O
seven-equation	O
two-phase	O
flow	O
model	O
(	O
liquid	O
,	O
gas	O
,	O
and	O
interface	O
pressures	O
)	O
versus	O
the	O
obsolete	O
ill-posed	O
six-equation	O
flow	O
model	O
(	O
non-physical	O
mixture	O
sound	O
speed	O
)	O
found	O
in	O
RELAP5	B-Application
;	O
2	O
)	O
Improved	O
numerical	O
approximations	O
resulting	O
in	O
second-order	O
accuracy	O
in	O
both	O
space	O
and	O
time	O
versus	O
the	O
first	O
order	O
approximations	O
in	O
RELAP5	B-Application
;	O
3	O
)	O
Implicit	O
tightly	O
coupled	O
time	O
integration	O
for	O
long	O
duration	O
transients	O
,	O
such	O
as	O
providing	O
plant	O
behavior	O
for	O
full	O
life	O
fuel	O
cycle	O
evaluations	O
;	O
and	O
4	O
)	O
the	O
ability	O
to	O
easily	O
couple	O
to	O
multi-dimensional	O
core	O
simulators	O
being	O
developed	O
in	O
other	O
programs	O
(	O
NEAMS	O
,	O
CASL	O
,	O
ATR	O
LEP	O
)	O
.	O
</s>
