SINDA/FLUINT is the culmination of thermal/fluid software development
dating back to the 1960's when the CINDA code was developed by Chrysler
Aerospace. TRW revised the code for NASA in 1972 and renamed it
to SINDA, a precursor to several subsequent codes including Hughes'
CINDA (or HSCINDA), MITAS, and SINDA/G.
In 1982
the NASA/TRW version and MITAS versions were used as starting points
for SINDA/FLUINT (then called
SINDA '85 or SINDA-85, corresponding to its first release date).
In 1986 the fluid module, FLUINT, was first released, greatly
expanding the code. SINDA/FLUINT was well received and has successfully
supplanted many other SINDA versions and SINDA-like codes, becoming
a best-seller and a NASA Space Act Award winner (1991) in the process.
NASA continued to guide the development of SINDA/FLUINT until 1992
when the code was identified for commercialization by C&R Technologies.
Subsequent improvements over older SINDA codes include submodels,
registers and expressions (an underlying spreadsheet), design optimization and
test data correlation, statistical design methods, and a comprehensive
fluid flow analysis capability.
Originally intended
to satisfy the ever-changing modeling needs of the spacecraft and
launch vehicle thermal community, SINDA/FLUINT has diffused into
other industries such as nuclear, aircraft, electronic packaging,
HVAC, and automotive, and into other specialties and subsystems
such as cyrogenic and environmental control. SINDA/FLUINT is intended
primarily for designing and analyzing thermal and fluid systems
represented in electrical analog, lumped parameter form. Given properly
prepared inputs, SINDA can also solve both finite difference and
finite element equations: it is better classified as an “equation
solver” than its traditional classification as a “finite difference
solver.”
SINDA/FLUINT is
now arguably the most advanced one dimensional thermal/hydraulic
code available, solving arbitrary fluid flow networks without presuming
the application. The networks may contain single-phase vapor or
liquid as the working fluid, or combinations of liquid and/or vapor
at various locations in the network, and even mixtures of working
fluids. These networks are solved in conjunction with one or more
accompanying thermal networks, accounting for the energy flows in
and out of the fluid system(s).
The improvements
that yield the most analytic power, however, are hidden ... or at
least external to SINDA/FLUINT. Until the 1990’s, SINDA/FLUINT was
primarily used as a batch style code run with manually-generated
text input files, although archaic codes such as TRASYS were often
used to prepare certain inputs such as radiation factors. Now, thanks
to a new generation of graphical interfaces, SINDA/FLUINT is primarily
used as a “solution engine.” These interfaces include the nongeometric
sketch-pad-style Sinaps®, and more
recently the geometry-based Thermal Desktop®
(for SINDA conduction/capacitance calculations) with its companion
modules RadCAD® (SINDA
radiation calculations) and FloCAD® (FLUINT
circuits and convective heat transfer calculations). The latest
release of FloCAD, in particular, contains major expansions for
facilitated modeling of heat pipes
and single- or two-phase fluid loops coupled to the structural (nonfluidic)
thermal model. It has significantly improved the ease of use for
FLUINT modeling.