Our engineering staff is currently engaged in a variety of
analytical activities -- mostly related to NASA's advanced jet propulsion technology.
We are also developing associated software computational tools and a low-cost, high-strength
composite material. Representative examples are cited below.
Foreign Object Damage Diagnosis
One of our current NASA software development projects involves establishing
a capability to determine if a turbine engine has suffered foreign object damage (FOD).
And, if so, which specific components have been damaged and how severely.
This is being accomplished using a combination of gas path measurement data
from sensors, mathematical models of engine thermodynamic performance, and
analytical diagnostic techniques. A computational software tool entitled FOD
facilitates the implementation of a weighted least squares/Kalman filter
approach that uses measured system responses to predict component
performance variances. The data from a parallel NASA effort to analyze
structural responses will be fused with the aerothermodynamic response data
to yield a more reliable FOD diagnostic tool.
SUA Tool Development
The SUA tool developed under NASA sponsorship and described in the
N&R Capabilities link is currently being ported from the PC platform
to SGI-Motif platforms. New features are also being added to SUA to enhance
is functionality. For example, the Beta distribution has been added to
add flexibility in typical engineering situations where mean values and
standard deviations are unknown (statistical databases do not exist), but
engineers can nevertheless estimate a most likely value and upper and lower
bounds. Also, the ability to plot the random variables distributions
on-screen and many other enhancements are being added.
Mistuning Analyses of Centrifugal Compressors
We are also currently developing methodology to perform
mistuning analyses of centrifugal compressor impellers using REDUCE and
ANSYS codes. The objectives are to: (1)quantify
the impact of random mistuning on component fatigue
lives, and (2) evaluate life improvement techniques.
Probabilistic Analysis of Space Station Power
We have recently performed a
probabilistic and sensitivity analysis for the power output
of the International Space Station Power System that accounts for
uncertainties in the Earth's albedo, station attitude error,
battery capacity, battery charge-discharge unit
efficiency, and DC/DC converter efficiency
using SPACE and FPI codes.
Poly-Wire Composite Material
Under NASA sponsorship we are developing Poly-Wire -- a high strength steel
wire reinforced polymer composite. Compared to carbon or glass fiber
filled polymers, it is expected to provide superior fracture toughness
and residual fatigue life to structures which have stress risers such as
holes or sharp corners or are vulnerable to impact damage. Bending or
torsion stiffness can be easily tuned to desired levels by the location
of nets in the matrix.
Education Outreach for NASA
The Education Outreach program at N&R Engineering
is developing student knowledge programs in aeronautics
for grades K through 12. This includes
educational products, aeronautic storyboards,
and videoconferences. An example educational game
developed for NASA can be seen at
www.ueet.nasa.gov/StudentSite
Adaptive Control System for Jet Engines
We are currently developing adaptive control systems for
aircraft gas turbine engines as part of NASA's Autonomous
Propulsion System Technology Project (APST). This control
will compensate for engine performance deterioration
due to component degradation to allow increased
autonomous operation of the Aircraft Propulsion
Control System, and a higher degree of independent
response to the Vehicle Management System.
Probabilistic Interface Codes
We are developing interfaces between leading
manufacturing codes such as DEFORM and PROCAST
and the probabilistic code NESTEM. The purpose is
to quantify the size and identify the location of
the defects that occur. This information will
be invaluable during manufacturing for designing
and maintaining aerospace components.
