c2r summerfall 2011

8/10/2019 C2R SummerFall 2011

http://slidepdf.com/reader/full/c2r-summerfall-2011 1/24

An PublicationAltair S U M M E R / F A L L 2 0 1

4 Simulation StreamlinesAircraft Door Development

8 Bird Strike Simulation

Takes Flight

17 Inside a NASA Production

Supercomputing Center

Ideas and Strategies In Product Development



Cradle North America Inc.70 Birch Alley Suite 240, Beavercreek, OH 45440

Phone: +1-937-912-5798 Fax: +1-513-672-0523 [email protected]

Why Cradle CFDWhy Cradle CFD

Access SC/Tetra & STRThrough Altair HyperW

Choosing CFD software is a crucial step of a long termcommitment. The last thing you want after investing in

personnel, training, and hardware, is to discover that the

software you chose won’t do what you need it to do. Here

seven reasons why Cradle’s SC/Tetra and STREAM CFD

software should be considered as part of your due diligen

Thermofluid Analysis System

with Unstructured Mesh

Thermofluid Analysis Systemwith Structured Mesh

Increase Your Confidence that

You’re Committing to the

Right CFD Software

Cradle software were

originally designed to work

on Windows PC and

not converted from UNIX.

This makes Cradle software

very efficient and capableeven when using standard PC

equipment.

Windows compatible7Cradle customers include

Canon, Panasonic, Sony,

Yamaha, Toyota, and many

others in the United States,

Canada and Asia Pacific.

Used by recognized

global companies6

Both offer full general

purpose functionality

including free-surface,

humidity/condensation, and

moving meshes. SC/Tetra

also simulates fully coupled

Human Body

Thermoregulation andCavitation.

The CFD committee (ed.), Geometry Da

Model Vehicle Used in Wind Tunnel Tes

for Prospective CFD Benchmark Tests

Japanese), Technical Report Series, JS

No.42, (2008).

General purpose

CFD software1Each contains

pre-processor, solver, and

post-processor sharing

common user-friendly

interfaces and providing

seamless integration.

SC/Tetra eliminates the need

to purchase additional 3rd

party grid software.

All inclusive2SC/Tetra unstructured grid

CFD software is used when

accurately modeling arbitrary

shapes and complex curved

surfaces is important.

STREAM structured grid CFD

software is used when fine

geometrical details are lessinfluential.

Unstructured and

structured grid products3

The Japanese Society of

Automotive Engineers (JSAE)

collected drag and lift data

for a 1/5 scale vehicle1 and

provided a 3D computer

model to CFD developers to

determine how well CFD can

predict zero degree yaw drag

and lift. SC/Tetra predicted

both CD and C

L within 1% of

the measured values 2.

Proven accuracy5

ThermofluidAnalysisSystem

withUnstructur edMesh


withStructured Mesh

Ultra-low memory

consumption solver (5M

cell/GB of RAM) facilitates

running higher resolution

models.

4 Low memory consumpt

and fast solver

1

Shimano, K. Et al., Wind Tunnel Testing

JSAE Standard Low- aerodynamic-drag

Vehicle Body Using 1/5 Scale Model,

Review of Automotive Engineering, Vo

No.1, (2009).

2

http://www.cradle-cfd.c

Cradle North America Inc.

70 Birch Alley Suite 240, Beavercreek, OH 45440



Access SC/Tetra & STREAThrough Altair HyperWo

Choosing CFD software is a crucial step of a long term

commitment. The last thing you want after investing in

personnel, training, and hardware, is to discover that the C

software you chose won’t do what you need it to do. Here a


software should be considered as part of your due diligenc




with Structured Mesh



Right CFD Software



on Windows PC and



very efficient and capable

even when using standard PC

equipment.






Used by recognized

global companies6







Human BodyThermoregulation and

Cavitation.

The CFD committee (ed.), Geometry Data

Model Vehicle Used in Wind Tunnel Testin

for Prospective CFD Benchmark Tests (in

Japanese), Technical Report Series, JSAE

No.42, (2008).

General purpose







SC/Tetra eliminates the needto purchase additional 3rd








software is used when finegeometrical details are less

influential.

Unstructured and







model to CFD developers todetermine how well CFD can



both CD and C

L within 1% of


Proven accuracy5


withUnstructuredMesh

ThermofluidAnalysis System

withSt ructuredMesh

Ultra-low memory




models.

4 Low memory consumptio

and fast solver

1

Shimano, K. Et al., Wind Tunnel Testing of

JSAE Standard Low- aerodynamic-drag


Review of Automotive Engineering, Vol. 3

No.1, (2009).

2

http://www.cradle-cfd.com

Cradle North America Inc.

70 Birch Alley Suite 240, Beavercreek, OH 45440



Access SC/Tetra & STRThrough Altair HyperW

Choosing CFD software is a crucial step of a long term

commitment. The last thing you want after investing in

personnel, training, and hardware, is to discover that the

software you chose won’t do what you need it to do. Here


software should be considered as part of your due dilige




with Structured Mesh



Right CFD Software



on Windows PC and



very efficient and capable

even when using standard PC

equipment.






Used by recognized

global companies6







Human BodyThermoregulation and

Cavitation.

The CFD committee (ed.), Geometry D

Model Vehicle Used in Wind Tunnel Te

for Prospective CFD Benchmark Tests

Japanese), Technical Report Series, J

No.42, (2008).

General purpose







SC/Tetra eliminates the needto purchase additional 3rd








software is used when finegeometrical details are less

influential.

Unstructured and







model to CFD developers todetermine how well CFD can



both CD and C

L within 1% of


Proven accuracy5


withUnstructuredMesh


withStructuredMesh

Ultra-low memory




models.

4 Low memory consump

and fast solver

1

Shimano, K. Et al., Wind Tunnel Testin

JSAE Standard Low- aerodynamic-dra


Review of Automotive Engineering, Vo

No.1, (2009).

2

http://www.cradle-cfd.co



Landing Success with

Simulation and Optimization

James R. ScapaChairman and CEO,

Altair Engineering, Inc.

Over the last few years, Altair Engineering, Inc. has continued to expand its business. This

year, we are on track to earn over $200 million in revenue, representing a 20% increase

over last year. We attribute this performance to steady growth in markets where we are the

market share leader, such as automotive, as well as growth that is outpacing the industry in

advanced manufacturing segments such as aerospace, shipbuilding, marine, heavy industry and rail.

In fact, aerospace represents our fastest growing market. In 2011, we anticipate an annual growth

rate of 35% as we help customers employ simulation and optimization techniques to develop products

ranging from innovative jet engines to lightweight aircraft structures. Our HyperWorks analysis solu-

tions enable engineers to rapidly analyze, explore and optimize designs to dramatically reduce develop-

ment time and costs.

To assist aerospace and other customers meet both engineering and business challenges, Altair is

investing in several areas. With regard to modeling, visualization and automation, we recently acquired

SimLab, a process-oriented, feature-based, finite-element modeling software for solid structures. With

productivity gains in excess of five times for certain classes of problems, we will be working to identify

opportunities to leverage this technology and philosophy more broadly through our product offerings.

To address simulation, data capture and data management issues, we recently introduced collabora-

tion tools in HyperWorks 11.0. These capabilities bring an intuitive, user-centric experience for manag-

ing personal and team CAE data and processes without leaving the HyperWorks environment. We see

providing immediate productivity benefits to our HyperWorks community, without impacting current

CAE workflow processes, as an integral step towards evolving an enterprise simulation data managementstrategy.

In the realms of predictive analytics and optimization, we are adding evermore robust features to

RADIOSS, OptiStruct and MotionSolve. Through our acquisition of ACUSIM and its AcuSolve

computational fluid dynamics (CFD) technology, HyperWorks now offers a powerful portfolio of solvers

for linear, nonlinear, multi-body dynamics and CFD problems. AcuSolve uniquely provides the added

advantage of being tightly integrated with our structural analysis and optimization solutions to allow our

customers to solve complex fluid-structure interaction and multi-physics problems.

With respect to technology that addresses our customers’ business challenges, we continue to invest

heavily in PBS Works, our suite of on-demand cloud computing technologies for maximizing computing

infrastructure assets. Leveraging this platform, we just introduced HyperWorks On-Demand, a solution

that leverages our patented licensing system to provide access to HyperWorks and a scalable high-per-

formance computing infrastructure through a secure Web-based platform. In addition, we are providing

organizations with unparalleled decision-making power through our HiQube business intelligence solu-tions, which deliver in-depth business analytics and reporting capabilities for the largest data sets.

Through the unique combination of our people, best-in-class simulation technology, open-architec-

ture system and our patented HyperWorks Unit business model, Altair provides customers with the tools

to take their businesses to new heights – and land success.

Altair focuses on simulation, predictive analytics andoptimization, leveraging high-performance computing that

promotes innovative engineering and business decision-making.

www.altair.com/c

2Concept To Reality Summer/Fall 2011

L E T T E R F R O M T H E C E O



Software

Altair delivers design, engineering and analytics

software that balances performance, weight and

cost so companies can create more advanced,

protable products.

Consulting

By combining its technology with a deep

understanding of the product life cycle,

Altair collaborates with clients to develop

products that are sustainable from the start.

Delivering Solutions for

High-performance Products

Attention aerospace community!

Complete a short, online survey for a chance to win

an iPad at www.altair.com/C2Raerosurvey

HyperWorks | Altair ProductDesign | PBS Works | solidThinking | HiQube | ilum


http://slidepdf.com/reader/full/c2r-summerfall-2011 6/24www.altair.com/c


P R O C E S S A U T O M A T I O N

Simulation

StreamlinesAircraft DoorDevelopment

The Eurocopter Group, owned by

the European Aeronautic Defense

and Space (EADS) Company,

develops commercial a nd military

helicopters for the global market and is also

involved in European Airbus programs

through its aircraft doors and fairings busi-

ness unit. The company was created in 1992

through the merger between the helicopter

division of Aerospatiale-matra (France) and

DaimlerChrysler Aerospace (Germany).

Eurocopter products and services involve

many disciplines including design, production,

flight tests, continuing airworthiness, train-

ing, maintenance and quality. The main

objective for all disciplines is to ensure the

safety of the aircraft.

Equally important is to deliver innovative

products to meet customers’ needs in some 150

countries. As part of this focus on innovation,the company looks for ways to increase the per-

formance and efficiency of aircraft components,

including closure systems. Eurocopter’s imple-

mentation of state-of-the-art software helps to

ensure safety and to improve performance

while automating the door analysis process.

The Eurocopter Group

leverages analysis to cut

design time and automatethe process of developing

safe aircraft closures.

By Michele Macchioni



Door to DoorClosure systems are complex, with

many integrated parts. Whether theyare being developed for helicopters or

other aircraft, the doors must open, close and

work in emergency situations.

From product to product, we cannot start

with the same hypotheses. Door systems are

built according to each aircraft’s size and gov-

ernmental regulations.

The development process entails balancing

different requirements. The closure systems

must be robust in capabilities but light in

design. The design must fulfill customers’

requirements, even as these requirements

change. And, development must be completedon time to be in sync with client critical-path

program milestones.

In general, the company must meet

requirements for reliability, packaging,

weight, manufacturability and cost.Drilling down, engineers evaluate

structural and kinematic properties of the doors

with the objective of harmonizing the con-

straints and delivering doors that are designed

to operate for the service life of the aircraft and

safely in evacuation situations. Simulation tools

enable Eurocopter to virtually assess the perfor-

mance and robustness of designs through an

iterative design analysis process.

Stepping through DevelopmentWhen you think of an aircraft door, con-

sider its structural components as well asinterfaces to the fuselage. Structural compo-

nents include the door frame, beams and edge

Optimizing a Door Support Arm

In addition to stress engineers employing simulation tools,

Eurocopter’s engineering team includes optimization specialists

whose job it is to investigate innovative designs for aircraft doors

and components. A case in point is a recent door support arm

for the Fairchild Dornier 728 aircraft. Using Altair’s structural

optimization software, engineers achieved a weight reduction ofapproximately 20% in its design.

Altair OptiStruct topology optimization technology was used within the Eurocopter design

process. Engineers were able to create design concepts – taking into account performance

and product objectives – without having to develop, evaluate and iterate on multiple CAD

design proposals.

The initial door hinge design provided by OptiStruct maximized the stiffness for three load

cases: door blocking, emergency opening and damper hit. In addition, draw direction

constraints were included as part of the optimization, yielding a design tailored to the

specific method of manufacture. Secondary analyses further reduced the part mass by

optimizing the shapes and sizes of ribs for all load cases and a maximum allowable stress

level.

The results were impressive. Eurocopter reduced the door support arm weight by approxi-

mately 20% without compromising the stiffness of the part. In addition, the turnaround time

to develop and validate the new door support arm design was reduced from three months to

three weeks.

Also, Eurocopter has successfully applied optimization tools on other projects. For example,

engineers have simulated stop brackets and hinge arms as well as optimized the weight of

the entire door system on a regional jet.

www.altair.com/c2r Concept To Reality Summer/Fall 201

5


Simulation enables engi-

neers to analyze forces on

door components (above

left) and von Mises

stresses (above right).

Passenger door with

support arm

Initial Design

Eurocopter reduced

the door support arm

weight by ~ 20% and cut

design time by 75%.

Final Design



Reducing weight is the objective, and components must

be optimized by fulfilling all of the requirements. These are

formalized by means of constraints – such as stiffness and

stress – among the selected load cases. Manufacturing con-

straints, such as the maximum shell thickness or type of

material to be used, are also considered. This concept is

valid when referring to global calculations or to a single

component.

As part of the process, we develop three types of finite-

element models (FEMs). For example, the global FEM

represents the global structure, which is provided by the air-

plane manufacturer and is a coarse model. The intermediate

FEM is typically used to evaluate load cases; these models

are more refined. The detailed FEMs, for stress analysis, are

very refined and created for local investigations.

Depending on the component, we define the connec-

tions and the material; then, we decide which type of model

to run. Altair’s modeling and visualization simulation tools,

HyperMesh and HyperView, allow us to rapidly respond to

changes in design specifications and loads and make revi-

sions very quickly.Our previous pre- and post-processing solutions did not

enable us to process models as quickly. One of the primary

drivers to migrate to the Altair HyperWorks suite was to

keep on track in terms of our deadlines.

In making the move, we also discovered the customiza-

tion capabilities of the software. In the f ramework of

creating global models of the door system, for instance, we

leveraged HyperWorks’ scripting language to support the

automation of batch meshing and the model organization

process for specific analyses and solvers.

Being able to tailor HyperWorks for our workflow pro-

cesses and environment has resulted in several benefits. For

example, we have more control over parameters such as

material and rivets, for which we have constructed proprie-

tary databases. HyperWorks also provides a homogeneous

pre- and post-processing environment. Together, these have

contributed significantly to reducing our CAE cycle times.

The gains that we have made in the Stress Department

– in creating models to specific standards in weeks vs.

months – have been recognized by other engineering

departments within Eurocopter. In fact, an initiative is

under way to transfer these best practices to other parts of

the company as Eurocopter works toward harmonizing its

tools and processes.

Through the HyperWorks open-architecture and script-

ing language, Eurocopter has reduced development time by

automating repetitive tasks, even as designs have changed

late in the process. We have also established a framework to

build models to standards, thus helping to enable qualityassurance and reliability.

Michele Macchioni for Eurocopter Deutschland stress

engineering.


7


For more information on HyperWorks,

visit www.altair.com/c2r.



Bird strikes have been occurring for more than a

century. In fact, Orville Wright was the first to

report a bird strike in 1905.

In the United States, the Federal Aviation

Administration (FAA) notes that bird strikes occur during

daylight hours, usually during a plane’s approach and land-

ing roll. Ninety-two percent of the strikes take place at orbelow 3,000 ft above ground level. Gulls, doves and pigeons

account for approximately one-third of the encounters.

According to USA Today, which analyzed FAA data,

severe collisions between airborne jetliners and birds have

soared over the past two years. In 2009, severe bird strikes

above 500 ft hit a high of 150; 2010 had a similar number of

bird strikes. Although the FAA is pushing airports to do a

better job of keeping birds away from runways, serious inci-

dents above 500 ft are taking place.

The FAA certifies civil aircraft to meet a series of mini

mum standards. Aircraft must be designed and built to fly

safely as well as survive situations in which internal o

external factors – such as bird strikes – may interfere with

safe operations. To address these regulatory requirements

many aircraft manufacturers are turning to simulation tech

nology in product development.

Making an ImpactRecent events have highlighted the dangers from bird

strikes in flight. The famous US Airways Hudson Rive

emergency landing was the result of two engine failure

from bird strikes (see photo above). At a minimum, bird

strikes cause damage to the airframe that adds repair costs

At the other end of the spectrum, they can cause cata

strophic damage potentially resulting in a crash and loss olife. Many airports are implementing changes to reduce bird

populations around their facilities to reduce incidents.

The airplane manufacturers still are required to con

duct bird strike tests and design structures that ca n

withstand a bird strike event. That is why a key goal in

product development is to deliver airframes and engine

that pass regulatory requirements on the first test. Failure

to do so results in redesign, refabrication, retesting – and

lost time, money and effort.

www.altair.com/c


D E S I G N S T R A T E G I E S

Bird Strike SimulationTakes Flight

The increasing number

of bird-plane impacts gives

rise to new CAE methods

to address aircraft safety.

By Robert Yancey



Following the lead of the automotive

industry with virtual crash testing, many air-

plane manufacturers a nd suppliers areturning to virtual simulations of bird strike

events. Success here with explicit nonlinear

dynamic transient analysis codes such as

RADIOSS from Altair Engineering can dra-

matical ly reduce costs and improve

performance.

The Power of the ProcessBird strike analysis is far different than

automotive crash analysis. Various finite-

element methods have been used, but the

method that is becoming a standard in bird

strike analysis is the SPH method, based onsmooth particle hydrodynamics. This tech-

nique allows the kinetic energy of the bird

test article to be imparted to the structure

while allowing the bird to break apart and

disperse (see images to the right).

The analysis is set up to reproduce the

standard regulatory test method. Some air-

craft companies use gelatin to represent a bird

while others employ actual test articles. As the test arti-

cle impacts the structure, it disperses, much like a water

balloon hitting the ground.

The SPH computational method models the bird test arti-

cles with a set of “particles” (disordered points) that intersect


9


The underbelly fairing is an area of an airplane at risk

to bird strike events. As a secondary structure,

lightweight composite material constructions are

desired for underbelly fairings. Through a combination

of advanced structural optimization capabilities in

OptiStruct and the SPH computational methods in

RADIOSS, both developed by Altair Engineering, Inc.,

aircraft manufacturers have the ability to streamlinecomposite material designs taking into account bird

strike impacts.

To incorporate a bird strike event as a load case within a

composite optimization process, kinetic energy, velocity

and deceleration information, together with the

deformation limit desired, first need to be calculated to

estimate the static equivalent loads on the structure.

Using OptiStruct, an optimization analysis can then be

performed to determine the optimal shape, thickness

and order of each ply in the stack – taking into account

the static equivalent loads for the bird strike event

simultaneously with the fairing’s frequency targets and

static load cases.

Subsequently, one would need to consider the most

critical locations for a bird strike and then add reinforce-ment to those areas. For example, sections of the fairing

covering critical components – such as fuel tanks, flight

control electronics, etc. – would need to have adequate

reinforcement to withstand a bird strike event. A

potential approach would be to perform the worst-case

bird strike analysis, using RADIOSS, to determine a

minimum thickness in those areas to ensure flight

safety, then use this minimum thickness constraint in

those zones in the OptiStruct optimization run.

Optimizing Composite Underbelly Fairings for Bird Strike Events

The images above depict the use of the smooth particle hydrodynamics

(SPH) methods with RADIOSS software for bird strike analysis.



Initiatives to advance aviation technology are under

way at the National Institute for Aviation Research

(NIAR) at Wichita State University. Located in

Wichita, Kan., the “Air Capital of the World,” NIAR,

an Altair research partner, is the largest university

aviation Research & Development institution in theUnited States.

NIAR is able to integrate business, government and

academia in cooperative efforts to advance aviation

technology; a key example of this is NIAR’s Computa-

tional Mechanics Laboratory. This cutting-edge

laboratory provides research focused on the develop-

ment and application of numerical methods in the

areas of crashworthiness, structures, numerical

optimization techniques, virtual product development

and certification.

According to the Computational Mechanics Technical

Director Dr. Gerardo Olivares, the lab is currentlycollaborating with an aerospace industry advisory group

and researchers at NASA Glenn to develop and validate

numerical modeling techniques to simulate bird impacts

on aircraft structures. Additionally, current ongoing

research includes a joint sponsored project by the

Federal Aviation Administration, aerospace companies

and seat suppliers on Certification by Analysis

of Aircraft Seat Structures. The objective of

this project is to develop numerical modeling

techniques to

support the dynamic

certification process

of aircraft seat

structures per

Advisory Circular20-146.

The aerospace industry is conservative by nature, and

Dr. Olivares notes that pressure to reduce development

costs and cycles is driving companies to introduce

advance simulation tools in the design, development

and certification process. However, since many current

engineers have not been exposed to the technology,

there is a lack of qualified staff trained to apply the use

of advanced analysis tools.

The Computational Mechanics Lab at NIAR plays a key

role in solving this problem. It hires 12 to 16 graduate

students, training them to use a combination ofadvanced simulation tools, analytical skills and experi-

mental methods, all of which are critical in the aircraft

design process. “From the lab, we expect the students

to move into industry where they can either create or

join existing advanced simulation groups and transfer

the technology,” says Dr. Olivares.

with each other through external

forces rather than connections to

nodes. As such, the results areinsensitive to the deformation of

the birds – but provide a clear

understanding of the strike impact

on the structure.

The SPH method is well-suited

to hydrodynamic material (and the

bird material law is mainly hydro-

dynamic). It’s based on interpolation

theory and allows any function to

be expressed in terms of its values at

a set of particles. In addition, it per-

mits the motion of a discrete

number of particles to be followedin time.

In the actual simulation process, the target structure i

modeled from CAD data as a finite-element model. Th

most important features are connection characteristics (rivets) and material behavior (plasticity, rupturing).

The RADIOSS bird strike simulation process include

rupture checks and estimates on the bird’s residual energy in

case of penetration, number of broken rivets, and behavio

of the rupture zone to predict the risk of debris separating

from the structure and possibly impacting another part o

the aircraft. An additional consideration is the ability of the

vehicle to fly after impact despite damage inflicted (change

in aerodynamic characteristics due to deformation).

Though one single simulation is not very CPU-intensive

many simulations are required to assess the sensitivity of the

structure, the number of possible impacts on various zone

of the structure a nd the dispersion of impact typ(incidence). Therefore, optimization and sensitivity analysi

Aviation Research: From Lab to Industry

For more information on NIAR, visit www.niar.wichita.edu.

Bird strike impact on a metallic

leading-edge structure

www.altair.com/c



Bird strike simulation and

physical test results on awing leading edge showing

consistent failure modes.



software may be useful to limit the number of simulations

that need to be car ried out and to properly assess the

phenomenon involved in such events.Typically, aircraft manufacturers build physical rigs to

carry out physical testing. They marry the results of the phys-

ical and simulation testing to improve product development.

Through rigorous physical and virtual testing correlation

efforts, the bird strike test articles deliver the right kinetic

energy to the structure, which is important in this type of

simulation. Altair provides certification correlation test

results for virtual bird models of various types and sizes that

can be run with RADIOSS. These results have been corre-

lated with impacts on wings, nacelles and engines.

The Simulation DifferenceIn summary, many aircraft OEMs and suppliers have

improved their bird strike analysis process on several fronts

by using virtual simulation. Altair has been a partner with

many of these companies, providing the technology and

expertise to make these efforts successful. The cost of per-

forming simulations is considerably less than conducting

multiple physical tests. Additionally, a greater number ofsituations can be analyzed and the effects of design changes

can be evaluated very quickly, allowing for the optimization

of components for weight.

What’s more, simulation tools have saved time in the

process. Simulation provides confidence in the design so

that physical testing can run in parallel with production

with a high level of success. The goal is getting the design

right the first time – and simulation has proven in many

applications to provide the right answers before any physical

evaluations are attempted.

Robert Yancey is Executive Director, Global Aerospace, Altair

Engineering, Inc, Troy, Mich.

For more information about RADIOSS and

bird strike analysis, visit www.altair.com/c2r.


11

Acoustics, Noise Vibration and HarshnessCoustyxCoustyx is an analysis software for simulating acoustic phenomena and optimizing

NVH performance.

For more information, contact:

Advanced Numerical Solutions, LLC

3956 Brown Park Drive Suite B

Hilliard OH 43026

[email protected]

www.coustyx.com

Benefits:

• Allows very large models (1 million DOFs);

• Parallel implementation on shared memory, multi-core processors to

yield faster solutions; and

• Most comprehensive selection of Boundary Condition options, and

built-in acoustic wave sources.

“Coustyx is the most advanced Boundary Element (BE) software package

on the market today. Not only does it incorporate the Fast Multipole Method

(FMM) in its solver, it uses iterative techniques to quickly converge to the

solution, instead of solving the problem directly.“Unlike other BE software packages, Coustyx has thought of all the details.

No more fighting the program to try and export your data in a user-friendly

format. No more endless stipulations to incorporate the FMM solver into

your model. And best of all, no more wading through the useless help file, or

wondering if the technical support crew will be getting back with you. Coustyx

is simply the best out there.”

Daniel Tengelsen, Researcher,

Brigham Young University


A D V E R T I S E M E N T




T H E A R T O F I N N O V A T I O N

Alliant Techsystems Inc. (ATK)

Aerospace Systems, headquartered

in Magna, Utah, U.S.A., produces

solid rocket propulsion systems

and is a leading supplier of military and com-

mercial aircraft structures. It also has extensive

experience supporting human and space pay-

load missions.

That experience came into play on a

recent project for the National Aeronauticsand Space Administration’s (NASA) Orion

Multi-Purpose Crew Vehicle (MPCV).

ATK served as the subcontractor responsi-

ble for the Launch Abort Motor, designed

to lift the space crew module off the pri-

mary launch vehicle in an emergency

on the launch pad and during

launch up to 300,000 ft of flight.

StructuralOptimizationHelps LaunchSpace PayloadsAerospace company employs

simulation software to

reduce weight in the Launc

Abort Motor manifold for the

Orion Multi-Purpose

Crew Vehicle.

By Blaine E. Phipps, Michael H. Young andNathan G. Christensen

The innovative Launch Abort Motor turn-

flow nozzle manifold designed by ATK

Aerospace Systems awaits static testing.


http://slidepdf.com/reader/full/c2r-summerfall-2011 15/24www.altair.com/c2r Concept To Reality Summer/Fall 201

13


ATK conducts a ground test of the Launch

Abort Motor at its facility in Utah.

The optimized titanium manifold (left) weighs

approximately 1,000 lbs versus the steel version

(right), which weighs around 2,000 lbs.

The manifold is designed so that combustion

thrust gases create a pulling force on the crew

module to lift it out of harm’s way.

The Launch Abort Motor – 17 ft long, 3 ft in diameter

and capable of generating a half-million pounds of thrust –

was designed to include composite motor case turn-flownozzle manifold technology to reduce overall launch system

weight, critical to space missions, while ensuring crew

safety. Unlike conventional rocket motors, the innovative

exhaust turn-flow manifold is positioned at the forward end

of the motor – so that the combustion thrust gases are com-

pressed evenly through four nozzle ports angled away from

the crew capsule (aft) end, creating a forward-thrust reac-

tion (pulling force) on the crew module.

The initial design, steel manifold, weighed slightly less

than 2,000 lbs and supported an early concept flight test

(see YouTube “Pad Abort 1”). However, to meet the weight

target of 1,300 lbs or less, ATK and Lockheed Martin Space

Systems Company agreed to change the manifold materialto a high fracture toughness titanium for the much lower

weight, flight weight nozzle manifolds. Using specialized

optimization techniques, ATK further reduced the mani-

fold weight by 300 lbs while meeting a ll strengt h

requirements and deflection limits.

Lighter is BetterWhen launching payloads into space, every pound saved

matters. So when the project allocated new mass require-

ments to hit per formance requirements, further weight

reduction throughout the launch abort system was needed.

Although already within the weight budget, to support the

program, ATK stepped up to further reduce weight on the

Launch Abort Motor nozzle manifold using structural opti-

mization on the entire manifold.

ATK engineers pursued a two-phased simulation strat-

egy. This approach applied operational pressures and line

loads to both computer simulations and to a physical test

specimen in a specially designed test fixture. The test speci-

men validated computer simulations of motor operation in a

complex flight loading environment.

ATK had a team of ballistics, structural, fluids and

thermal engineers working on this complex project. The

optimization problem was set up in the following manner.

First, engineers identified the design variables and designspace, which also included external surfaces of the mani-

fold body.

Next, the responses of what could be measured were

established. The mass and the von Mises stress in the mani-

fold also needed to be considered.

The final objective was to minimize the manifold mass

using a simulation-driven design methodology for the

given constraints’ performance target.



Alliant Techsystems Inc. (ATK) is a Fortune 500

aerospace, defense, security and sporting

company with more than 18,000 employees and

operations in 24 states, Puerto Rico and internationally. It

was launched as an independent company in 1990 when

Honeywell spun off its defense businesses to sharehold-

ers. ATK Aerospace Systems, ATK Armament Systems,

ATK Missile Products, and ATK Security and Sporting

comprise the business lines.

ATK expanded into the aerospace market with the

acquisition of Hercules Aerospace Company in 1995 and

Thiokol Propulsion in 2001, which transformed the

company into the largest supplier of solid propellant

rocket motors and a provider of high-performance

composite structures.

ATK Aerospace Systems products and services include

solid propulsion systems and rocket motors; advanced

composite structures and components; and satellite

structures, components and systems. In addition, this

business structure provides advanced antennae and

radomes for weapons and ships, energetic materials,

military flares and decoys, and space engineeringservices.

As part of ATK Aerospace Systems, ATK Space Launch

Systems is focused on NASA’s human spaceflight

programs. Space Launch products include the Space

Shuttle’s Reusable Solid Rocket Motor, the abort motor

for NASA’s Orion MPCV Launch Abort System, the

Booster Separation Motors and Booster Deceleration

Motors for the Space Shuttle and Liberty Launch Vehicle.

FocusedForward

www.altair.com/c



Getting Off the GroundOptimization of the flight weight nozzle manifold

offered its own set of challenges considering thatalong with the approximate 60% weight density reduc

tion, the modulus of elasticity is also reduced abou

60% compared to steel. This complicates many struc

tural issues in the nozzle manifold such as strain

deflection limits and joint rotations at critical sea

interfaces. Switching from titanium to steel is not sim

ply trading out the materials!

The optimization model started with the baseline

steel manifold working towards an optimized fligh

weight manifold using titanium mechanical properties

Next, engineers “smoothed” all external surfaces of the

steel manifold configuration, making uniform thick

ness thrust ports. These actions reduced the weight othe steel manifold from approximately 2,000 lbs to

1,300 lbs on the titanium design.

ATK engineers then analyzed the performance o

the manifold/nozzle assembly taking into consideration

operational pressures based on computational fluid

dynamics (CFD) results and axial line loads. Later, vir

tual simulations on t he manifold/hydroproof tes

fixture were performed to determine a proof test pres

sure that would envelope the stress response in the

manifold for operational conditions.

Since the proof test is the most severe loading envi

ronment, the manifold was optimized to the proof tes

loads and configurations.

The Outer LimitsBecause requirements dictated that the manifold’

inner-profile remain u nchanged, the only way to

reduce weight was to remove material from the outside

profile. The topological optimization methodologie

employed in Altair Engineering, Inc.’s OptiStruct were

chosen for the task.

OptiStruct’s free-shape optimization capabilitie

enabled engineers to treat every node on the outer surface

of the manifold’s finite-element model (FEM) as an indi

vidual design var iable. OptiStruct then automaticallygenerated shape design variables for each surface node so

that each node could move inward or outward as needed

Stress and displacement constraints were prescribed

for the manifold weight optimization, and the operationa

pressure loading was applied. As the optimization pro

ceeded, the outer profile of the manifold started to thin

where it could without violating the stress, strain or dis

placement constraints.


http://slidepdf.com/reader/full/c2r-summerfall-2011 17/24www.altair.com/c2r Concept To Reality Summer/Fall 201

15


ATK also employed simulation

to determine proof test pressure

loads to validate the manifold for

predicted operational loads.

As part of the iterative process, the configuration of the

nodes changed during the thinning process, requiring

engineers to remesh some of the manifold’s components.

The nozzle ports, for example, were slightly out of round as

a result of the port geometry and the distribution of the

pressure loads. It was critical to keep the nozzle stiff so it

wouldn’t deflect too far when under nozzle thrust loads and

adversely affect the motor’s performance. In addition, the

integrity of the seals between the primary and secondary

O-ring joints needed to be verified; the software predicted

O-ring gaps between both interfaces.The operational analysis determined a stress value for

the motor. Because those stresses were well under stress

threshold levels, the optimization cycle was repeated until

the manifold reached optimum weight.

Proof TestThe second part of the two-phased strategy involved

optimizing the mani fold to the proof test loads

and configurations. For the titanium manifold proof test

configuration, mounting the manifold onto a composite

pressure vessel was simulated and a thrust relief piston

attached to each of the nozzle ports. Fluid was pumped into

the system to simulate the operational pressures.

During an operational flight, there is a variable internal

pressure dist ribution within the manifold. To simulate

actual flight conditions in the proof test, the thrust relief

piston was designed to move down, reacting thrust loads at

each of the nozzle port locations to simulate axial thrust

and pressure loads.A FEM of this test proof configuration was used in the

optimization process. A study was performed to determine

what proof pressure was required in the proof test configu-

ration to match operational stresses.

Engineering requirements for the test simulation were

constant pressure inside the manifold and axial and sym-

metric boundary conditions, including an axial thrust load

over 500,000 lbf.



On a Mission

The Orion Launch Abort System (LAS) was

designed to save astronauts’ lives in the event

of a malfunction of the launch vehicle. NASA

envisioned the components including a fairing

assembly that covered the crew vehicle, a motor

stack and a nose cone.

The fairing assembly would protect the crew module

from atmospheric debris, aerodynamic pressure and

heating, and the abort motor exhaust plumes. The

motor stack would include three solid propellant

motors that would carry out the abort, attitude

control and jettison functions. The nose cone would

make the vehicle aerodynamic as it traveled through

the atmosphere.

In May 2011, NASA announced that the Orion crew

exploration vehicle would serve as the agency’s new

Multi-Purpose Crew Vehicle for robust human

exploration beyond low Earth orbit. Currently NASA

is planning to continue with the Lockheed Martin

current crew capsule design and is expected to

utilize the entire flight weight Launch Abort System

on future launch systems. Also, it is expected that

the R&D efforts that went into developing the

Launch Abort Motor will be applicable and aid future

space programs.

www.altair.com/c



Given the data, the required proof pressure was deter-

mined to achieve an envelope operational stress. The

pressure load was adjusted so that the desired stress limits

in the part would be at least as great as operational flight.

Automation AssetsPrior to using OptiStruct, manual methods were

employed to approach similar problems. FEMs were built,

estimating where material should be removed, and then

the models were rebuilt. Each iteration could take half a

day or more.

Using the simulation software, it was discovered that

the optimization routines were taking material out of

places which were not intuitive. OptiStruct did all the

work. Consequently, ATK engineers did not need to createnew geometry models, FEMs or boundary conditions for

each iteration.

What previously took months to determine by trial and

error was reduced to days with OptiStruct. Overall, design

time was cut on this project by 30% – and weight reduced

from 1,300 lbs to approximately 1,070 lbs. What’s more,

the maximum stress in the manifold came in under the

constraint value.

A Solid SolutionThe Launch Abort Motor Nozzle Manifold did not lend

itself well to conventional physical testing. ATK needed to

innovate at every step, coming up with ways to develop the

loads, perform design iterations, carry out the proof testing

and replicate a complex loading environment. Simulation

software enabled ATK to find a solid solution to this engi

neering challenge.

Simulation software was essential to the Launch Abor

Motor Nozzle Manifold redesign. OptiStuct was critical to

meeting and exceeding the ta rget weight goal on th

Launch Abort Motor.

Blaine E. Phipps is a Senior Struc tural Engineer at ATK

Aerospace Systems; Michael H. Young is a Project Engineeat ATK Aerospace Systems; and Nathan G. Christensen i

Manager of the Engineering Tools & Analysis Section at AT

Aerospace Systems, Brigham City, UT.

For more information about Altair OptiStruct,

visit www.altair.com/c2r



P h o t o c o u r t e s y o f N A S A A m e s R e s e a r c h C e n t e r


17

T R E N D S I N T E C H N O L O G Y

In the past, scientific and engineering advancements

relied primarily on theoretical studies and physical

experiments. Today, however, computational model-

ing and simulation are equally valuable in such

endeavors, especially for an agency such as the National

Aeronautics and Space Administration (NASA). With amission “to pioneer the future in space exploration, scien-

tific discovery and aeronautics resea rch,” the use of

high-end computing (HEC) for high-fidelity modeling and

simulation has become integral to all four of NASA’s mis-

sion directorates: aeronautics re search, exploration

systems, science and space operations.

These HEC resources are provided at NASA’s Advanced

Supercomputing (NAS) Division at Ames Research Center,

Moffett Field, Calif . NAS offers production a nd

development systems to U.S. scientists in government,

industry and at universities, with users currently numbering

over 1,500. Projects such as designing safe and efficient

space exploration vehicles, projecting the impact of human

activity on weather patterns and simulating space shuttle

launches are studied using the facility’s supercomputers.“We provide world-class HEC and associated services to

enable NASA scientists and engineers in all mission direc-

torates to broadly and productively employ large-scale

modeling, simulation and analysis for mission impact. We

pursue a future where these services empower ever greater

NASA mission successes,” says William Thigpen, the HEC

capability deputy project manager at the NAS Division.

The facility’s current HEC systems include four super-

computers, a 30-petabyte mass storage system for long-term

By Cathleen Lambertson

Inside a NASA ProductionSupercomputing Center

Over 45 miles of InfiniBand® double data rate cabling is required to connect Pleiades 11,712 nodes.



data storage, two secure front-end systems requiring two-

factor authentication and two secure unattended proxy

systems for remote operations. Key system resources at NASinclude: Pleiades, a 111,872-core, 1.315 petaFLOPS (Pflop/s)

SGI® Altix® ICE cluster; Columbia, a 4,608-processor SGI

Altix® (Itanium 2); Schirra, a 640-processor IBM® Power5+;

and hyperwall-2, a 1,024-core, 128-node GPU cluster.

Since 300 to 400 jobs are typically running 24 hours a

day, seven days a week, the NAS staff works nonstop to

meet the demands for time on these machines. “Our mis-

sion is to accelerate and enhance NASA’s mission of

space exploration, scientific discovery and aeronautics

research by continually creating and ensuring optimal

use of the most productive HEC environment in the

world,” says Thigpen. “Our viewpoint is that we spend a

lot of money getting hardware in here, but it really makessense that it is effectively exploited by our users because

the bottom line is we’re not about big hardware, we’re

about big science and engineering.”

Building a Supercomputer – PleiadesOriginally installed in the fall of 2008, the Pleiades

supercomputer is an SGI Altix ICE 8200/8400 InfiniBand®

cluster with Intel® Xeon® quad and hex-core processors, run-

ning at 1.09 Pflop/s on the LINPACK benchmark – the

industry standard for measuring a system’s floating-point

computing power. Considered one of the most powerful

general-purpose supercomputers ever built, each of the

Pleiades 184 racks (11,712 nodes) has 16 InfiniBand switches

to provide the 11D dual-plane hypercube that provides the

interconnect for the cluster. The InfiniBand fabric intercon-

necting Pleiades’ 11,712 nodes requires more than 45 miles

of cabling. Pleiades is the largest (measured by number of

nodes) InfiniBand cluster in the world (see sidebar for full

system specifications).

Currently ranked seventh on the TOP500 list of the

world’s most powerful computers, the Pleiades supercom-

puter was built to augment NASA’s current and future

high-end computing requirements. “Pleiades is a general-

purpose machine and provides for all three components of

supercomputers – [capability, capacity and time critical],”says Thigpen. “We have users running jobs using over

18,000 cores, providing new insights into the formation of

the universe. There are numerous users running parameter

studies (often thousands) using from one to a few thousand

cores. Pleiades is also being utilized to answer time-critical

questions concerning the shuttle.”

The most recent upgrade to Pleiades occurred in May

2010 and included the incorporation of 32 SGI ICE 8400

racks with the Intel Xeon X5670 (Westmere) processor,

which effectively doubled the science and engineering com

pute capability to the NAS facility’s general user community

“Placing these racks into service involves the connection oover 4,400 cables. While 1,024 were done in the factory, the

rest had to be done on our floor,” notes Thigpen. “We then

performed an extensive series of tests at first focused on the

new racks and then on the total system. There are no other

systems with this many nodes connected via InfiniBand in

the world, and so we encounter and resolve issues tha

haven’t been seen elsewhere.”

According to Alan Powers, the HEC technical directo

for Computer Science Corp. at NAS, the goal of the upgrade

was to have an up-and-running production machine afte

the integration. “If you look at most other supercomputing

sites, it is hard for them to do this type of integration in thei

environment. We cut in these racks in two weeks, and nowthey are in production. We added 32 racks, which is consid

ered a very large machine to begin with at most sites, but we

just think of it as part of our system.”

Choosing Components and SoftwarePleiades was built to meet as many of the emerging NASA

science and engineering mission requirements as possible

while remaining within the HEC budget. “The Pleiade

architecture was chosen because it provided the best perfor

mance/cost ratio of the systems we looked at. Since its origina

installation in 2008, it has undergone two expansions. We

will continue to build it out as long as the fundamental eco-

nomics of the system remain sound, and the science and

engineering returns remain high,” states Thigpen.

To build Pleiades, NAS engineers began w ith the

components recommended by the vendor and those being

used on other systems. The result has been an easy

transition to the new environment for NASA users. “We

want an environment where the components complemen

each other, are an easy natural transition for our users and

provide a reliable environment,” says Thigpen. For example

the SGI ICE 8200 and 8400 are standard products that have

been taken to an extreme size at the NAS facility

Additionally, the InfiniBand network was expanded to

incorporate both the data analysis and visualization clusteras well as the storage system.

Another consideration is outlining and selecting a scal

able architecture. Powers explains, “We chose SGI because

it had a certain architecture that allowed us to build and

grow it. [It also had] the best price/performance based on ou

workload. Where we are today, we’re near a petaflop capabil

ity, and it’s been built over a couple of years; we’ve been

adding to it slowly. The other vendors’ price/performance

wasn’t even close to this platform.”

www.altair.com/c





P h o t o c o u r t e s y o f N A S A E x p l o r a t i o n S y s t e m s M i s s i o n

D i r e c t o r a t e ,

P r i n c i p a l I n v e s t i g a t o r , J o s e p h O l e j n i c z

a k


19


• 184 racks (11,712 nodes)

• 1.315 Pflop/s peak cluster

• 1.09 Pflop/s LINPACK rating (June 2011)

• Total cores: 111,872

• Total memory: 185 TB

• Nodes

5,888 Harpertown nodes

2 quad-core processors per node

Xeon E5472 (Harpertown) processors

Processor speed – 3 GHz Cache – 6 MB per pair of cores

Memory Type - DDR2 FB-DIMMs

1 GB per core, 8 GB per node

1,280 Nehalem nodes

2 quad-core processors per node

Xeon X5570 (Nehalem) processors

Processor speed - 2.93 GHz

Cache – 8 MB Intel® Smart Cache for 4

cores



4,480 Westmere nodes

2 six-core processors per node

Xeon X5670 (Westmere) processors

Processor speed - 2.93GHz

Cache – 12 MB Intel® Smart Cache for 6

cores



Subsystems

• 14 front-end nodes

• 1 PBS server

Interconnects

• Internode - InfiniBand, with all nodes connected in

a partial 11D hypercube topology

• Two independent InfiniBand fabrics

• InfiniBand DDR, QDR

• Gigabit Ethernet management network

Storage

• SGI® InfiniteStorage NEXIS 9000 home filesystem

• 12 DDN RAIDs, 6.9 PB total

• 7 Oracle Lustre cluster-wide filesystems

Operating Environment

• Operating system - SUSE® Linux®

• Job Scheduler – PBS Professional®

• Compilers - Intel and GNU C, C++ and Fortran

• MPI: SGI MPT, MVAPICH2, Intel MPI

Computational fluid dynamics (CFD) calculation of the flow

around the Orion crew module, with wind tunnel sting.

The Pleiades – System

Specifics

Managing the WorkloadWhen providing supercomputing resources to 1,500

users, 24/7, workload mana gement is a top priority.

Originally developed at NAS in the 1990s and then com-

mercialized, PBS Professional® workload management

software has been used since its inception. Commercially

developed by Altair Engineering, Inc., Troy, Mich., the

PBS platform is designed to power grid, cluster and on-

demand computing environments. PBS Professional is

used to manage all HEC resources at NAS, including

Pleiades. “We have found Altair continues to be receptiveto enhancements that NAS needs to manage unique sys-

tems. The choice for Pleiades was a natural progression

from years of a very effective working relationship with

Altair,” states Thigpen.

PBS Professional is a resource allocation tool that makes

it possible to create intelligent policies to manage distrib-

uted, mixed-vendor computing assets as a single, unified

system. Based on a policy-driven architecture, it continually

optimizes how technical HEC resources are used, ensuring





that they are used effec-

tively and efficiently. Simply

put, the software looks at the

jobs that want to run, looks at the

resources available for them to run on and

makes the best match based on a number of

criteria. “Those criteria can include the user that’s

running and how many jobs that user currently has run-

ning, or how many cores his job is currently using. It canalso be the queue that a user submits their job in, and those

queues can have things limiting them, like how many jobs

are running or how many cores all of the jobs together are

using. It also can be the mission directorate those users are

in,” explains Thigpen.

Powers adds: “The ‘P’ in PBS stands for ‘portable,’ and it

allows us to run this on any architecture. We’ve had PBS on

fat node architectures, on thin node clients and on IBM

architectures. PBS has been able to adapt to all those

c o m p u t i n g

envi ronments

This has allowed ou

users to have a consisten

set of batch scripts across these

different environments. They only

have to learn one thing. So one, it’

flexible; two, we can use it on any architec

ture; and three, it’s easy for users to learn.”

Your Own HEC EnvironmentAccording to Thigpen, HEC is an enabling technology

that allows a company to build products that can meet thei

customers’ requirements in a cost-effective manner: “By

spending a relatively small amount on a system, they can

run through hundreds or thousands of alternatives before

building a physical prototype. This will allow for a bette

product with lower production costs.”

However, there are many issues to address when consider

ing whether an HEC environment is the right choice for an

enterprise. “There has to be a balance between the cost of the

resources, the technology they enable, the increased produc

tivity of their staff, the potential return on their investmenand what their competition is doing,” Thigpen concludes.

Cathleen Lambertson is Contributing Editor, Tech Brief

Media Group.

The Pleiades

supercomputer

at the NASA

Advanced

Supercomputing

(NAS) facility

at NASA Ames

Research Center.

For more information on PBS Professional,

visit www.altair.com/c2r



Solver PowerIntroducing a new advanced CFD solver

and expanded linear and non-linear solutions

Collaborative Simulation ManagemenCollaboration tools making simulation

management natural and intuitive

Desktop IntegrationCAE pre- & post-processing within one

integrated desktop framework

Creating the Broadest

Open-Architecture CAE Solution

HyperWorks 11.0 demonstrates its commitment to

delivering the broadest CAE solution to the PLM market

by adding new products and a rich set of functionality

to the strong foundation of past releases.

Our goal at Altair has always been to provide the best

technology at the highest value to our customers, and the

HyperWorks 11.0 release is no exception.

Learn more about HyperWorks 11.0 at

www.altairhyperworks.com/hw11

1300 East 9th Street

Cleveland, Ohio 44114

Change Service Requested

PRSRT S

U.S. POST

PAIDST CLOUD

PERMIT#

c2r summerfall 2011

Documents