Table Of ContentReport Documentation Page Form Approved
OMB No. 0704-0188
Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information,
including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington
VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it
does not display a currently valid OMB control number.
1. REPORT DATE 3. DATES COVERED
2002 2. REPORT TYPE 00-00-2002 to 00-00-2002
4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER
NAVO MSRC Navigator. Spring 2002
5b. GRANT NUMBER
5c. PROGRAM ELEMENT NUMBER
6. AUTHOR(S) 5d. PROJECT NUMBER
5e. TASK NUMBER
5f. WORK UNIT NUMBER
7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION
Naval Oceanographic Office (NAVO),Major Shared Resource Center REPORT NUMBER
(MSRC),1002 Balch Boulevard,Stennis Space Center,MS,39522
9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S)
11. SPONSOR/MONITOR’S REPORT
NUMBER(S)
12. DISTRIBUTION/AVAILABILITY STATEMENT
Approved for public release; distribution unlimited
13. SUPPLEMENTARY NOTES
14. ABSTRACT
15. SUBJECT TERMS
16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF 18. NUMBER 19a. NAME OF
ABSTRACT OF PAGES RESPONSIBLE PERSON
a. REPORT b. ABSTRACT c. THIS PAGE Same as 28
unclassified unclassified unclassified Report (SAR)
Standard Form 298 (Rev. 8-98)
Prescribed by ANSI Std Z39-18
The Director’s Corner
Steve Adamec, NAVO MSRC Director
Sweeping Series of Enhancements
Engulf NAVO MSRC
The next few months will be notable ones here at ically important for us to redouble our efforts in
the NAVO MSRC. We are completing a sweeping assessing and implementing common user envi-
series of center enhancements, designated as ronments, practices, and tools within and across
Technology Insertion for FY02 (TI-02), across the SRCs. Your continuing individual and collec-
several major technology areas within the MSRC. tive user feedback makes it clear that you consid-
The centerpieces of TI-02 are the acquisition of a er this to be one of your highest priorities for the
new IBM POWER4 HPC system and completion SRCs. In response, the SRCs have intensified and
of the NAVO MSRC Remote Storage Facility made significant progress toward strategic cross-
(RSF). When complete, the TI-02 enhancements cutting collaborative efforts in technical areas
will provide almost 8.5 teraflops of aggregate such as mass storage and archival, metacomput-
peak computing capability with commensurately ing, HPCMP-wide shared information environ-
balanced storage and networking capabilities. ments, and security. Here at the NAVO MSRC,
The RSF will permit us to offer what is perhaps we are redoubling our efforts to supplement
one of the most resilient and best performing those activities by strengthening the links to the
HPC storage environments in the world today. new HPCMP Programming Environment and
This enormous computational capability, coupled Training (PET) program that's more tightly
with a sustained 11-year NAVOCEANO focus on focused than ever on user environment, tools,
supporting the largest and most demanding DoD and productivity.
computational applications, will continue to
My staff and I look forward to seeing you in June
enable unparalleled advances in the DoD science
at the 2002 HPCMP Users' Conference in Austin,
and technology areas served by the HPC
Texas. As always, please take every opportunity
Modernization Program (HPCMP).
to let us know how we can better serve you —
With all of this diverse computational capability your feedback is critically important to us and to
that's been fielded across 20+ shared resource the HPCMP.
centers (SRCs) by the HPCMP, it has become crit-
About the Cover:
This image was generated by the POP model running on HABU, an IBM RS/6000 SP located at the NAVO MSRC. The
simulation represents a state-of-the-art eddy-resolving effort that will eventually be used as the ocean component of a
coupled global air/ocean/ice prediction system for Navy needs as well as for short-term climate studies.
2 SPRING 2002 NAVO MSRC NAVIGATOR
The Naval Oceanographic Office (NAVO) Contents
Major Shared Resource Center (MSRC):
Delivering Science to the Warfighter
The NAVO MSRC provides Department of
The Director’s Corner
Defense (DoD) scientists and engineers with high
performance computing (HPC) resources, includ-
ing leading edge computational systems, large-
scale data storage and archiving, scientific visuali- 2 Sweeping Series of Enhancements Engulf
zation resources and training, and expertise in spe- NAVO MSRC
cific computational technology areas (CTAs).
These CTAs include Computational Fluid
Dynamics (CFD), Climate/Weather/Ocean
Feature Articles
Modeling and Simulation (CWO), Environmental
Quality Modeling and Simulation (EQM),
Computational Electromagnetics and Acoustics
(CEA), and Signal/Image Processing (SIP). 4 Active Swirl and Fuel Modulation to Control
Combustion Instability in Gas Turbine Engines
NAVO MSRC
Code N7
7 NAVO MSRC Visualization Center Supports
1002 Balch Boulevard
the Retrieval of the Ehime Maru
Stennis Space Center, MS 39522
1-800-993-7677 or
[email protected]
11 Knowledge Management: A Case for
Intelligent Data Archives
Scientific Visualization
13 Improvements in the Use of Color Wheel
NAVO MSRC Navigator Visualization of Global Modeling Data
www.navo.hpc.mil/navigator
14 Towards a High-Resolution Global Coupled
NAVO MSRC Navigator is a bi-annual technical
publication designed to inform users of the news, Navy Prediction System: The Ocean Component
events, people, accomplishments, and activities of
the Center. For a free subscription or to make
address changes, contact NAVO MSRC at the Programming Environment and Training
address above.
EDITOR: 18 VSIPL/ERI: An Enhanced Reference Implementation
Gioia Furness Petro, [email protected] of the Vector Signal and Image Processing Standard
DESIGNERS:
20 NAVO MSRC PET Update
Cynthia Millaudon, [email protected]
Kerry Townson, [email protected]
Lynn Yott, [email protected] The Porthole
Any opinions, conclusions, or recommendations in
this publication are those of the author(s) and do 22 A Look Inside NAVO MSRC
not necessarily reflect those of the Navy or NAVO
MSRC. All brand names and product names are
trademarks or registered trademarks of their Navigator Tools and Tips
respective holders. These names are for informa-
tion purposes only and do not imply endorsement
by the Navy or NAVO MSRC. 24 File Transfer Techniques: Transferring Between HABU
and Other Systems
Approved for Public Release Upcoming Events
Distribution Unlimited
27 Conference Listings
NAVO MSRC NAVIGATOR SPRING 2002 3
Active Swirl and Fuel Modulation to
Control Combustion Instability in Gas
Turbine Engines
Chris Stone and Suresh Menon, Georgia Institute of Technology
Combustion-generated pollutants such control techniques
as nitrous oxide (N O), carbon monox- (e.g., using struc-
2
ide (CO), unburned hydrocarbons tural changes)
(UHC), and soot can be reduced signif- cannot deal with
icantly if lean burning combustion sys- all possible
tems can be used in gas turbine changes, and
engines. However, as the fuel-air mix- therefore, in order
ture becomes lean, small perturbations to suppress these
in the flow can change the unsteady oscillations, active
heat release pattern, and if the heat control strategies
release is in-phase with the acoustic are needed. This
fluctuations in the combustor, the pres- article describes the
sure (acoustic) fluctuations can grow study of two active con-
into high-amplitude, low-frequency trol methods applied to pre-
oscillations. These oscillations can mixed combustion in a gas tur-
cause flame extinction (often called bine engine: modulation of the
Lean Blowout, or LBO), reduce engine swirl imposed on the incoming fuel- Figure 1(b)
life span, and/or cause catastrophic air mixture (which is at a fixed equiva-
structural damage under extreme cir- lence ratio) and modulation of the fuel upstream of the combustor. Fuel is then
cumstances. If these oscillations can be content in the premixed mixture for a injected into this swirling airflow in the
controlled and even leaner mixtures fixed swirl condition. These studies premixer so that a swirling, premixed
can be burned stably, then not only can have been conducted using a state-of- fuel-air mixture enters the combustor.
emissions be reduced but the over fuel the-art Large-Eddy Simulations (LES) Swirling inflow is used in dump com-
consumption can also be decreased sig- model developed at the Georgia bustors to exploit a fluid dynamic phe-
nificantly. Since these oscillations occur Institute of Technology. nomenon called Vortex Breakdown
in a dynamic manner, passive The first active control technique stud- (VB) that makes the flame zone com-
ied here employs modulation of the pact and stabilizes the flame. As the
inlet swirl velocity of the incoming swirling flow expands into the combus-
premixed mixture. In a typical tor, an adverse pressure gradient is
gas turbine engine, swirl is formed in the flow, and this slows down
introduced into the air the axial motion of the mixture. For a
from the compressor given geometry, when the swirl intensi-
by swirl vanes (typical- ty exceeds a critical value, a recircula-
ly small airfoils at high tion bubble is formed (called VB) along
angles of attack) in the the centerline of the combustor. This
premixer located bubble acts as an effective bluff body in
Figures 1(a)/(b).Swirl modulation effect on flame-vortex
dynamics:(a) high-swirl condition,(b) low-swirl condition.
At the high-swirl state,the vortex rings (purple) rapidly
break down,and the flame surface (gray) is compact.On
the other hand,at low swirl,the vortex rings are more
coherent,and they drag the flame with them,making the
Figure 1(a) flame longer.No VB occurs when the swirl is low,and
therefore,the flame in the low-swirl case oscillates and is
unstable,whereas at high swirl,VB stabilizes the flame.
4 SPRING 2002 NAVO MSRC NAVIGATOR
the flow, and along the centerline, the shared-memory parallel platforms (SGI an increase in swirl stabilizes the flame
flow from the inlet actually stops (stag- Origin 2000/3800). In fact, due to its and reduces the fluctuation in both the
nates) just upstream of the bubble. This scalability, LESLIE3D is now a bench- inflow mass flow rate and in the pres-
phenomenon helps to stabilize the mark code for all Department of sure fluctuations.
flame just upstream of the stagnation Defense (DoD) High Performance The governing physics of combustion
point. However, in current gas turbine Computing (HPC) sites and is being instabilities is quite complicated owing
engines, since the swirl vanes are fixed, used to evaluate new systems’ per- to the fact that not one, but several
formances. The current study
the swirl introduced into the flow is stat- physical processes are coupled and in
employed 1.3 million grid cells and
ic and is typically optimized for only contention. The dominant process for
required approximately 1000 CPU
one operating condition. This study combustion instabilities is the interac-
hours (on HABU) for one flow-through
explores how swirl magnitude can be tion of acoustic waves (pressure fluctua-
time. Typically, 10-15 flow-through
actively changed to stabilize the com- tions) with the unsteady heat source (in
times are simulated to obtain sufficient
bustion as the fuel air mixture is this case, the flame surface). When the
data for statistical analysis.
changed from rich to lean. pressure (p') and heat-release fluctua-
The first investigation looked at chang- tions (q') are "in-phase" (the product of
The second technique studied here is
ing the level of swirl imposed at the the two being positive), energy is
the dynamic adjustment of the fuel
inlet. In an open-loop study conducted added to the instabilities. As the fuel
content in the fuel-air mixture. For a
earlier, the pressure fluctuation was concentration is decreased, two impor-
fixed mass flow rate and a fixed inlet
shown to reduce when swirl intensity tant controlling parameters, the com-
swirl intensity, we dynamically change
the fuel-air mixture ratio by changing
the equivalence ratio of the incoming
mixture. The goal of this study is to
determine how changing the fuel con-
tent (which, in turn, will affect the
amount of heat released and peak tem-
perature reached) will affect the com-
bustion dynamics in the combustor.
The LES methodology is used here to
simulate the combustor response to
both control techniques. In LES, the
large scales of motion are fully resolved
in both space and time, and only the
small scales (smaller than the grid reso-
lution) are modeled. Premixed com-
bustion is modeled using a thin-flame
model in which a scalar field that repre-
sents the propagating flame front is Figure 2.Mass flux measured at the inlet during swirl modulation.At low swirl,
evolved, along with the LES momen- the fluctuating mass flux is nearly 100% but drops sharply as the swirl vane
tum and energy transport. To model angle is increased (i.e.,when the swirl velocity is increased).The pressure fluc-
tuation in the combustor is also decreased as the swirl intensity is increased.
the fuel-air mixture change (in the sec-
ond control technique), an additional
(conserved) scalar equation is mod- was increased. To dynamically repro- bustion temperature (flame tempera-
eled, which tracks the change in local duce this effect, a simulation was start- ture) and the burning velocity (flame
equivalence ratio. The local equiva- ed with a low-swirl S (0.56), and then speed), are subsequently reduced. The
lence ratio is then used to calculate the swirl was steadily increased so that S nearer one is to the LBO limit, the
burning rate and combustion tempera- reached a final value of 1.12. Analysis more pronounced is this effect (See
ture. shows that after a small delay, the pres- Figure 3a). At a lower burning velocity,
sure oscillation amplitude dropped by unsteady flames are more susceptible
The LES algorithm (LESLIE3D) is par-
6.6 decibels (dB). Figures 1 and 2, to large-scale flow perturbations since
allel (using Message Passing Interface)
respectively, show the effect of swirl on the recovery time (i.e., the time need-
and performs very well on a variety of
vortex-flame dynamics and on the ed to return to the mean or stable
distributed (Cray T3E (SEYMOUR),
mass flow-rate fluctuations. Results
RS/6000 SP3 (HABU), etc.) and Article Continues...
show that for a fixed fuel-air mixture,
NAVO MSRC NAVIGATOR SPRING 2002 5
Figure 3(a) Figure 3(a)/(b).Instantaneous view
of fuel modulation control.Shown
are the flame surface (red isosur-
face),vortex rings (gray rings),prod-
uct temperature (color contours),
and fluctuating pressure signal
(shown below the figure).In (a),the
fuel mixture entering the combustor
has become lean,and this results in
a decrease in temperature (blue
core region),and the pressure oscil-
lation increases.This time corre-
sponds to the far right of the p'(t)
signal.In (b),the inflow fuel mixture
equivalence ratio is increased (rich
mixture),and as a result,the flame
temperature increases,resulting in a
hotter core region (red temperature
contours).At this phase of the con-
trol cycle,the pressure fluctuations
5 begin to decrease (first quarter of
the p'(t) signal).
0
-5
location) is lengthened. In the pres- flow in a confined domain: acoustic not only to achieve stable combus-
ent simulation, the magnitude of waves, vortex motion, and unsteady tion in a regime that is not possible
flame fluctuations is reduced at high- heat release due to combustion. otherwise, but also to understand
er burning velocities (See Figure 3b). Active control of this instability, as how the dynamics have been
Another contributing factor to the demonstrated here, can then be used changed due to control actuation.
increased stability is the modification
of the relevant time scales. As the
Figure 3(b)
combustion temperature is altered,
the acoustic velocity (speed of
sound) is also modified, resulting in a
shift in the phase between the pres-
sure and heat-release fluctuations.
This effect can be significant in either
increasing or decreasing the instabili-
ties, depending on the phase
between the p' and q'. In some com-
bustion devices, instabilities are more
intense for higher equivalence ratios
due to this effect, while, as simulated
here, the reverse may also occur.
Simulations such as these can be
used to understand the complex 5
nature of combustion instability that
0
is a result of nonlinear interactions
between the three modes of wave -5
motion in a compressible reacting
Acknowledgements
This work was supported in part by General Electric Power Systems and Army Research Office (ARO). Computational support
was provided by the DoD High Performance Computing Modernization Program Office (HPCMO) at HPC Major Shared Resource
Center (MSRC) sites (Naval Oceanographic Office (NAVO), U.S. Army Engineer Research and Development Center (ERDC), and
Army Research Laboratory (ARL)), under an ARO Challenge Project.
6 SPRING 2002 NAVO MSRC NAVIGATOR
NAVO MSRC Visualization Center
Supports the Retrieval of the Ehime Maru
Pete Gruzinskas, NAVOMSRC Visualization Center
On 9 February 2001, a collision speed and direction, temperature, er resolution (500-m) nest, that
between a U.S. Navy submarine and salinity fields. Initially, a 2-km bounded the operation area just
and a Japanese fishing trawler sent grid that covered the entire south of Oahu. The model was run
the fishing vessel to the bottom of Hawaiian Islands was generated, but on the newest and most powerful
the Pacific Ocean about 10 miles this model provided input to a high- supercomputer at the NAVO MSRC,
south of Diamond Head, the RS/6000 SP3 (HABU).
Oahu, Hawaii. The decision
Part of the NAVO MSRC
was made to retrieve the ves-
Visualization Center mission is
sel, which lay in approxi-
the development of analytical
mately 1800 feet of water. A
software environments for the
Crisis Action Team was
Department of Defense (DoD)
formed, and the NAVO
research community. Some of
MSRC Visualization Center
these tools, designed to ana-
was asked to provide visuali-
lyze ocean model output,
zation support for the Ehime
were modified to analyze the
Maru Retrieval Operation.
Navy's operational model out-
There are many support
put. These software tools pro-
aspects in an operation like
vided significant diagnostic
this, but the first challenge
capability, which assisted in
was to visualize the high-res-
the validation of the model
olution model output gener-
output in a very complex
ated by the Shallow-Water
environment.
Analysis and Forecast System
While virtual environments
(SWAFS) a three-dimension-
may not provide all of the
al (3D) ocean circulation
answers to data analysts, the
model that produces time-
Screen capture of SWAFS probe compared to
series images with correct
the ADCP current measurements.
Article Continues...
SWAFS surface currents in the operational area. Vertical profile of SWAFS over the Ehime Maru.
NAVO MSRC NAVIGATOR SPRING 2002 7
fact of the matter is the real world ocean model analysis is portability was critical to the provision of an
environment is in 3D. Features with- — the ability to run on a variety of analysis environment and data to
in the environment have 3D struc- hardware architectures, including forward-deployed personnel on-
ture that can be difficult, if not laptop computers. scene at the recovery site. Other
impossible, to realize in two-dimen- support products were developed to
Portability is accomplished by savvy
sional (2D) space. The same tech- render the recovery area in 3D from
application of graphics techniques,
nology that was built to help high-resolution bathymetry (water
as well as smart Input/Output and
research and development modelers depth) data to delineate critical
memory management. This ability
scrutinize their model output areas. Conceptual animations
was applied to an opera- were built to demonstrate
Shallow-Water Recovery Site Deep-Water Recovery Site
tional scenario where the the mechanics of an
21º17.52’N 21º04.85’N
speed and direction of extremely difficult recovery
157º56.40’W 157º49.46’W
the ocean currents were operation.
critical factors.
The operation was success-
An additional feature ful, and all mission objec-
added to the application, tives were accomplished.
unique to the Ehime This recovery operation
Maru retrieval operation, demonstrates the excellent
was the display of an synergy that has developed
Acoustic Doppler Current between the operational
Profiler (ADCP) buoy. Navy and the DoD
The display of the ADCP research infrastructure built
data provided analysts a by the High Performance
direct comparison Computing Modernization
between model output Office (HPCMO), and is a
and in-situ current meas- Final Relocation Site stellar example of the
urements in near-real 21º1.00’N NAVO MSRC realizing the
time. Another significant 158º7.86’W HPCMO maxim of
feature of the virtual "Delivering Science to The
3D shaded relief of OPAREA using high-resolution
environments built for bathymetry collected by the USNS SUMNER.Imagery Warfighter."
shows where the ship was resting,the shallow-water
retrieval area,and the final relocation site.
02 days Particle 02 days Particle
22 hours Pick On 22 hours Pick On
59 minutes 59 minutes
0 45 Speed (cm/s) 0 45 Speed (cm/s)
Screen capture showing ocean currents at depth Another snapshot of currents at depth.Note the leg-
over an exaggerated (3:1) model of the Ehime Maru. end has been "tuned" to accentuate faster currents.
8 SPRING 2002 NAVO MSRC NAVIGATOR
Still images from conceptual
animation showing retrieval of
the Ehime Maruby the vessel
Rockwater.
Still image from conceptual animation showing the lift pro-
cedure.A conceptual animation was generated depicting
how the towing harness would be attached to the Ehime
Maru,which rested in approximately 1800 feet of water.
Still image showing Ehime Maruretrieval over real
bathymetry data.The animation was designed to concep-
tualize/visualize what the recovery would look like in the
context of the real data collected by the USNS SUMNER.
NAVO MSRC NAVIGATOR SPRING 2002 9
