Company:

Aeronautical Development Agency (ADA)

Products:

MSC Nastran
Patran

Industries:

Aerospace
Defense

Aeronautical Development Agency - Certified To Fly

Overview:
Fighter aircraft typically carry a number of different under-wing external stores such as fuel tanks, bombs and missiles. The geometrical and inertial parameters of these stores have an influence on the flight envelope and the flutter characteristics of the aircraft. An imported aircraft is certified by the OEM for the carriage of certain stores within a specified envelope. However, if the country which has acquired the aircraft decides to integrate a new store, then it has to either approach the OEM to help in the certification process or devise a mechanism to carry out the exercise itself. The former approach has a twofold disadvantage: violation of secrecy and also the prohibitive cost. Hence, it is imperative that an independent approach, along with the local certification authorities, be evolved to achieve the required objective.
Challenge:
Determine unsteady air loads due to the structural vibration modes at various altitudes and speeds
Results Validation:
“The excellent correlation between FE based flutter analysis and flutter analysis based on GVT data validated the use of this method on the second aircraft, the one with a new store requiring flutter clearance.”
Benefits:
  • Accurate FE Model Reproduction
  • Reliable Analysis
  • Improved Design Process

 
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Company:

System Design Evaluation Ltd.

Products:

Adams

Industries:

Aerospace
Defense

System Design Evaluation Ltd. - High Performing Mechanisms

Overview:

In the design of any new high explosive ammunition, the most complex and often problematic component is the fuzing system. The fuze must incorporate a Safe and Arm device to ensure that the projectile may only enter the armed state following exposure to firing forces and after reaching a safe distance from the muzzle of the weapon. Engineers at System Design Evaluation Ltd. (SDE) in Hertfordshire, UK have constructed rigid and flexible body MSC Adams models to study the motion and strength of the design of fuze mechanisms to identify potential design issues and assist with analysis of trials results.

“Conducting live firing ammunition trials is an expensive business,” said Eva Friis, Project Manager for the APEX ammunition development programme at Nammo Raufoss, Norway. “Analysis of recovered fuzes to determine the cause of failure is little short of forensic science and it is difficult to know how the forces imposed during recovery of the projectile affect the results. The Adams simulations have provided an insight into the operation of the fuze and enabled the team to highlight and address weaknesses with the design before manufacture and physical testing.”

Challenge:
The Nammo 25mm APEX projectile is a next generation armour-piercing, high-explosive ammunition designed for use with the US F-35 Joint Strike Fighter aircraft. The projectile leaves the muzzle of the 4-barrelled GAU-12 weapon system with a velocity of around 1,000m/s and experiences a peak setback acceleration of almost 80,000g. Under these conditions, coupled with severe space restrictions, it is almost impossible to instrument the fuze in order to gain an understanding of the operation and interaction of components inside. Therefore, while physical testing can be used to confirm functionality of the fuze, it often offers only limited information for post analysis in the event of a failure to function.
Solution:

Adams modeling has proven invaluable in providing information to assist with the diagnosis of evidence gained from recovery tests. In one case, examination of the internal components of the fuze after recovery tests showed markings which indicated a malfunction had occurred. A detailed flexible body Adams model of the design was developed, and analysis confirmed the nature of the problem and sequence of events within the fuze mechanism; huge centrifugal forces due to projectile spin resulting in deformation of internal components sufficient to result in the unlocking of two retaining gears.

Computer modeling of ammunition fuzes has not been without challenges. Safe and Arm devices are often mechanical and operate using clockwork escapement mechanisms, similar to those found in wrist watches. Such mechanisms rely heavily on 3D contact, leading to extended run times. Further, fuze arming times are largely dependent on the definition of frictional algorithms within the models. SDE has worked closely with fuze manufacturers to overcome this and validate models against static spin tests thereby providing a firm basis from which to investigate further design permutations.

Results Validation:
The Adams results have not only successfully predicted the failure of components on numerous occasions within various fuze designs, but have also facilitated in the redesign of components to achieve suitable strength. Importantly, by quantification of stresses within components, Adams has assisted in proving compliance with required safety factors, information which is not possible to glean from live firing trials results.
Benefits:
•Cost Reduction
•Invaluable Diagnostic Evidence
•Design Optimization

 
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Company:

Aerovironment

Products:

MSC Nastran

Industries:

Aerospace
Defense

Aerovironment - Optimizing Aircraft Performance

Overview:
The Global Observer is an unmanned aircraft with the wingspan of a Boeing 767 but less than 10% of the weight designed to provide communications and sensing for flights lasting up to one week at up to 65,000 feet. With a maximum wing loading of only 3.5 pounds per square feet, the wingtip deflects greater than 22 feet at its design limit load.
Challenge:
Wing load testing to demonstrate that the wing can withstand the stress experienced as a result of normal operation in turbulent air as well as requisite aircraft maneuvers.
Benefits:
  • Extensive Composites Modeling
  • Parametric Design Solutions
  • Optimized Design Performance

 
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Company:

American BOA

Products:

MSC Nastran
SimXpert

Industries:

Automotive
Motorsports

American BOA - Reduces Time to Develop Exhaust Expansion Joints From 5 Weeks to 2-3 Weeks

Overview:

American BOA specializes in the engineering and production of thinwall flexible metal components and systems for automotive and industrial applications. The company frequently creates new designs to meet the requirements of automobile original equipment manufacturers (OEMs). The damping characteristics and stiffness of the flexible joints are configured to optimize the noise vibration and harshness (NVH) characteristics of the vehicle. In the past, American BOA used engineering formulas to develop a rough design and then built and tested the physical prototypes in 6DOF (Degrees Of Freedom) for characteristics and durability to finetune the designs, which took about five weeks.

Challenge:

Reducing time to develop exhaust expansion joints

Results Validation:
  • Simulated Expanded Physics
  • Improved Design Performance
  • Validated with Physical Test
Benefits:
  • Reduce Development Period of Exhaust Expansion Joints From 5 Weeks to 2-3 Weeks
  • Simulated Expanded Physics
  • Improved Design Performance
  • Validated with Physical Testing

 
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Company:

Schneider Electric Dupont

Products:

Digimat

Industries:

Electronics

Dupont - Stiffness of a Bracket in Reinforced PBT

Overview:
Government regulation and unexpected fluctuations in raw material price levels create new challenges for many companies. DIGIMAT offers the perfect combination of material modeling platform to optimize the performance of our reinforced thermoplastic components and DIGIMAT has demonstrated its ability to provide robust and accurate prediction of materials behavior.
Challenge:
  • Predict structural response of a glass fiber filled PBT polymer bracket
  • Accurately design and optimize electrical components existing geometry
Solution:
  • Reverse engineering of an elasto-plastic DIGIMAT material model
  • Computation of the nonlinear stiffness based on fiber orientation prediction performed with Moldflow
  • Comparison with experimental stiffness for two different composite materials developed by DuPont:
    • 20% glass fiber reinforced PBT polymer, (material 1) 
    • 50% glass fiber reinforced PBT polymer, (material 2)
  • Material damage behavior is not modeled
Results Validation:
"…From REACH legislation to unexpected fluctuations in raw material price levels, our products are more than ever challenged, in this context DIGIMAT offers the perfect combination of material modeling platform to optimize the performance of our reinforced thermoplastic components and DIGIMAT has demonstrated its ability to provide robust and accurate prediction of our materials behavior." M. Oubahmane Innovation & Technology Specialist Schneider Electric
Benefits:
  • Stiffness at break computed with standard elastoplastic materials leads to 85% error for part in material 1 and to 120% error for part in material 2.
  • Stiffness at break computed with elastoplastic DIGIMAT materials leads to 5% error for part in material 1 and to 2.5% error for part in material 2.
  • Process design can be trustfully optimized with DIGIMAT to improve part performances at better cost.

 
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Company:

JSOL Corporation

Products:

Digimat

Industries:

Automotive

JSOL Corp. - Engine Backfire in an Air Intake Manifold

Overview:
“Fiber reinforced plastic becomes major material for intake manifold because of lightweight and heat resisting properties. Detecting the correct high stress concentration area is important to predict fatigue properties of manifold. DIGIMAT helps us to predict correct stress distribution by taking into account the fiber orientation coming from injection molding. "
Challenge:
  • To comply to the environmental needs of automotive industry and deliver greener technology by weight saving
  • To support the process of design of under-­-the hood plastic parts reinforced with glass fibers
Solution:
  • Calibration of an elasto-plastic DIGIMAT material
  • Simulation of the load case with Digimat-CAE/LS-DYNA interface based on fiber orientations coming from injection molding
  • Comparison of maximum principle stresses of the composite material with an isotropic calculation
Results Validation:
"Fiber reinforced plastic becomes major material for intake manifold because of lightweight and heat resisting properties. Detecting the correct high stress concentration area is important to predict fatigue properties of manifold. DIGIMAT helps us to predict correct stress distribution by taking into account the fiber orientation coming from injection molding. " Noriyo Ichinose, Sales engineer, JSOL Corporation, Japan
Benefits:
  • For the high pressure peak (t1 = 8 ms) and the low pressure region (t1 = 12 ms) significant differences in the stress distribution are observed compared to the simulation using isotropic material
  • The fiber reinforced part shows lower stresses than the isotropic case pointing out an over-designed part
  • Potentially further weight can be saved on the part by introducing DIGIMAT in the design cycle

 
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Company:

Ticona GmbH

Products:

Digimat

Industries:

Automotive

Ticona - Force Response of a Sun Roof Bearing

Overview:
Digimat was used to model the plastic injection of a sun roof bearing part, taking into account fiber orientations predicted by injection molding. There existed very good correlation with experimental failure data. Digimat was able to predict critical failure location in the part.
Challenge:
  • To correctly model fiber reinforced plastic parts
  • To have quantitative and predictive results from FEA
  • To use a unique material description valid for all kind of different load cases
Solution:
  • Calibration of an elastoplastic micromechanical DIGIMAT model based on dumbbells from a plate cut 0° and 90° with respect to highly oriented fibers
  • Setup of two different load cases (global & local) with different isotropic approaches and via DIGIMAT multi-scale modeling
Results Validation:
"Ticona’s intent is to provide solutions to our customers. Speed and quality of CAE predictions are key factors when we work on new components. Customers expect working solutions based on detailed structural response predictions and optimized mold design. From the results of our practical tests, the use of DIGIMAT to link Moldflow with Ansys structural analysis proved to be a very good way to fulfill these customer needs." Ulrich Mohr­-Matuscheck, Leader Design CAE, Ticona GmbH
Benefits:
  • With the scaling approach two different factors have to be applied to match the experimental force displacement curve of the global and local load case
  • Only the micromechanical DIGIMAT model describes correctly both load cases based on one unique material model taking into account fiber orientations predicted by injection molding simulation
  • In good correlation with experimental failure DIGIMAT per-­-phase results point out the critical location in the part

 
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Company:

Sovitec

Products:

Digimat

Industries:

Consumer Products

Sovitec - Material Design for Particle Reinforced Polyamide

Overview:

This study allowed Sovitec to obtain the arguments necessary in order to be more effective in the prospection of new markets, but also to consolidate its image of serious in the presentation of technical results in the plastic industry. Clearly a Plus.

Challenge:
  • Replace existing glass fiber reinforcement technology by solutions based on glass beads
  • Provide equal or improved material performance with the new solution
  • Reduce cost of material production
Solution:
  • Calibration of micromechanical material models for PA6/GF30 and PA6/GB30 based on experimental results
  • Virtual compounding of new material mixture in Digimat-MF
  • In-depth micro investigation of promising candidates by Digimat-FE
  • PA6/GF15/GB15 provides same composite stiffness in fiber direction and transverse to fiber direction
  • 15% of glass beads lead to an isotropisation of thermal properties
  • 15% of glass beads lead to an improvement of failure strength
Results Validation:
"This study allowed Sovitec to obtain the arguments necessary in order to be more effective in the prospection of new markets, but also to consolidate its image of serious in the presentation of technical results in the plastic industry. Clearly a Plus." Frederic Juprelle, Business Unit Manager, Sovitec
Benefits:
  • 20% price per produced part
  • 29% cycle time per part
  • 4% part reject rate
  • Machine durability

 
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Company:

RHODIA

Products:

Digimat

Industries:

Consumer Products

Rhodia - Impact on a beam

Overview:
Being predictive in crash simulation is the dream of CAE engineers. The use of short fiber reinforced materials was putting this target out of range, because such materials have a variable anisotropy all over the part, associated to complex matrix behavior. No material model implemented in a code is able to capture this complexity level. Digimat to LS DYNA does. Associated with the Rhodia material database MMI confident Design™, Digimat CAE/LS DYNA is providing the best predictability level available on the market today.
Challenge:
  • To support their customers in the design of polyamide parts
  • To take into account the influence of fiber orientation for reinforced polyamide material
  • To provide the best material data possible to support simulation technologies
Solution:
  • Calibration of a strain rate dependent elasto-viscoplastic DIGIMAT material model sensitive to fiber orientation
  • Coupling to fiber orientation from Moldflow injection molding analysis by using the Digimat-CAE/LS-DYNA interface
Results Validation:
"Being predictive in crash simulation is the dream of CAE engineers. The use of short fiber reinforced materials was putting this target out of range, because such materials have a variable anisotropy all over the part, associated to complex matrix behavior. No material model implemented in a code is able to capture this complexity level. Digimat to LS-­-DYNA does. Associated with the Rhodia material database MMI confident Design™ , Digimat-­-CAE/LS-­-DYNA is providing the best predictivity level available on the market today. Rhodia is proud to offer this reliability to its customers." O. Moulinjeune, Simulation Expert at Rhodia Engineering Plastics
Benefits:
  • The Digimat-CAE/LS-DYNA analysis correlates very well with the experimental results
  • The peaks’ maximum force as well as their occurrence in time is matched well
  • It is crucial to take the fiber orientation into account when simulating fiber reinforced plastic parts

 
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Company:

bime

Products:

Digimat

Industries:

Aerospace
Energy

Bime - Damage Behavior of Highly Porous Ceramics

Overview:
The application of Digimat MF and Digimat FE gave insight into the influence of microstructure on the overall mechanical and brittle damage behavior of highly porous sound absorbing ceramics. Digimat gave the engineers at bime key in-sight into the elastic properties of these porous sound absorbing ceramics, that was necessary to reduce production cost and increase the material's strength.
Challenge:

 

  • In-depth investigation aiming at material design
  • Prediction of elastic properties of porous sound absorbing ceramics
  • Prediction of pure brittle damage with respect to microstructure
Solution:
  • Reverse engineering of the unknown material properties based on experimental results
  • Virtual compounding of different porous ceramics in Digimat-MF
  • In-depth micro investigation of porous ceramics by Digimat-FE
  • Numerical investigation of pure brittle damage at both micro and macro scales on the porous ceramics
Results Validation:
"The application of Digimat-­-MF and Digimat-­- FE paved the way for me to give an insight into the influence of microstructure on the overall mechanical and brittle damage behavior of highly porous sound absorbing ceramics. I was able to contribute to the improvement of material strength by new material design while keeping the good sound absorption." Reza Malekmohammadi Research Assistant, bime
Benefits:
  • Reduced cost of material production and characterization
  • Increased material strength with improved material design
  • Boosted cooperation between ceramic developer and acoustic user

 
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Company:

European Space Research and Technology Center

Products:

Digimat

Industries:

Aerospace

ESA/ESTEC - Thermo-mechanical Design of an Ultra-light Satellite Antenna

Overview:
Digimat offered the engineers at the European Space Research and Technology Center the tools they needed to bridge the gap between the Micro world and the Macro world. Using Multi scale modeling of advanced woven composite material Digimat can support a virtual design of an ultra light satellite antenna.
Challenge:
  • Satellite antennas have to be designed in a sturdy and reliable manner
  • There is no easy way to repair a satellite once it breaks down
  • The extreme sensitivity of the structure towards thermal loads has to be investigated under environmental conditions
Solution:
  • Multi-scale modeling of advanced woven composite material on 3 scales
  • Carbon/epoxy composite: homogenization of yarn properties
  • Triaxial woven fabrics (TWF): detailed analysis of a representative cell
  • Satellite antenna: simulation of the full structure based on an equivalent multi-layer shell model representative for TWF
Results Validation:
“DIGIMAT is able to bridge the micro to the Macro world. A great example of high-­-quality european know-­-how” Dr Julian Santiago Prowald, TEC-­-MSS Structures Section ESA/ ESTEC
Benefits:
  • Mean-field homogenization gives high quality prediction of yarn properties (stiffness & CTE)
  • Yarn properties used to compute accurate results for stiffness & CTE for TWF
  • Good prediction of displacement behaviour of the satellite antenna due to thermal loading

 
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Company:

L&L Products

Products:

Digimat

Industries:

Automotive

L&L Products - Impact on a Stiffener for Lower B-Pillar

Overview:
Digimat provides L&L Products with state of the art simulation methods which aid engineers in product development. The key advantage provided by Digimat coupled to Radioss and other CAE software is a drastic predictability improvement for glass filled polyamide materials. With an improved predictability, optimal and robust lightweight design is possible in the future.
Challenge:
  • To move towards greener technology by replacing classical metal design by composite structures
  • To use the outstanding performance of composite materials whilst tackling all additional difficulties arising from the injection molding process
  • High quality prediction of impact on a short fiber reinforced stiffener beam
Solution:
  • Strain rate dependent micromechanical material model for AKULON K224 HG7 supplied by DSM
  • Mapping of MOLDFLOW fiber orientations onto the structural mesh
  • Solution of a nonlinear multi-scale analysis with DIGIMAT coupled to RADIOSS
Results Validation:
"The key advantage provided by DIGIMAT coupled to Radioss and other CAE software is a drastic predictivity improvement for glass filled polyamide materials. With an improved predictivity, optimal and robust lightweight design is possible in the future." F. Braymand, Simulation Manager at L&L Products
Benefits:
  • Excellent correlation on the force-­-displacement curve with experiment
  • Excellent correlation on the failure location compared to experiment
  • Drastic improvement of predictivity enables robust and lightweight design focusing on cost efficiency based on advanced DIGIMAT CAE technology

 
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Company:

Integrative Simulation and Engineering of Materials and Processes

Products:

Digimat
Marc

Industries:

Aerospace

ISEMP - Curing of Carbon Fiber Reinforced Plastics (CFRP)

Overview:
“Digimat enables the engineers at ISEMP to perform in-depth studies of complex and realistic microstructures. As they continue to invest into the future they now base their simulation approach on the Digimat software, improving their own research method as well as the education of a new generation of simulation engineers."
Challenge:
  • Processing of CFRP results in residual stresses in the material
  • Residual stresses lead to micro-­-damage & failure of CFRP
  • Goal is to simulate residual stresses of a carbon fiber composite material at the micro scale with realistic topology
Solution:
  • Generation of RVE with continuous fibers and layered microstructure
  • Realistic RVE with stochastically distributed fibers
  • CAD geometry of RVE to be used with external solvers
Results Validation:
"DIGIMAT enables us to perform in depth studies of complex and realistic microstructures. As an invest into the future we base our simulation approach on the DIGIMAT software, both for our research and the education of a new generation of simulation engineers who will be experts in the modeling of materials." Prof. Vasily Ploshikhin, Airbus endowed chair for Integrative Simulation and Engineering of Materials and Processes
Benefits:
  • The FE-­Simulation of laminate layers with inhomogeneous properties enables a detailed analysis of stress distribution and possible origins for different types of micro defect formation
  • Highest stresses can be found at the fiber matrix interface
  • Matrix areas between very close fibers are under higher load
  • Fiber matrix interface between differently oriented laminate layers shows higher stresses

 
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Company:

CADF

Products:

Digimat

Industries:

Energy

CADFEM - Continuous Fiber Reinforcement in Wind Turbine Rotor Blades

Overview:
Digimat assisted the engineers at CADFEM to develop a more efficient wind turbine by closing the gap between advanced modeling of heterogeneous anisotropic and nonlinear materials. The possibility of taking into account the micromchanical properties of fiber reinforced plastics in wind turbines is another area Digimat can aid in the production process of green energy.
Challenge:
  • Design of bigger turbine blades with low weight & high rotational inertia
  • Optimal use of expensive high-­-end composite materials
  • Flexible & realistic simulation approach to investigate design concepts
Solution:
  • Multi-scale analysis based on ANSYS Composite PrepPost™ model
  • Describe GFRP and CFRP composites via a unique material modeling approach using the mean field homogenization on the microscopic scale in DIGIMAT
  • Fiber description taking into account isotropic or transversely isotropic properties
  • Systematic analysis of failure directly in the Epoxy and the fiber phases
Results Validation:
"DIGIMAT enhances our product portfolio and closes the gap towards advanced modeling of heterogeneous anisotropic and nonlinear materials. We see a large potential for taking into account the micromechanical properties of fiber reinforced plastics." Martin Kracht, Product Manager DIGIMAT at CADFEM GmbH - ANSYS Competence Center FEM in Germany
Benefits:
  • Failure indicators are in general much lower for carbon fiber than for glass fiber reinforcement Carbon fiber reinforced blade fails on different ply level compared to the glass fiber design
  • The usage of a transversely isotropic description for the carbon fibers is critically important for a realistic simulation approach

 
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Company:

SOLVAY Speciality Polymers

Products:

Digimat

Industries:

Consumer Products

Solvay - Fatigue Failure of Injection Molded Bow Limbs

Overview:
By using DIGIMAT the engineers at Solvay could clearly demonstrate the tight link between geometry, flow of material, fiber orientation and mechanical behavior. They successfully used the approach to evaluate the endurance of a number of different bow limb designs.
Challenge:
  • A manufacturer injection-molded plastic bows set the goal to produce the best bows for recreational archery on the market based on SOLVAY material
  • A new and apparently improved design of the bow limbs showed a reduced fatigue lifetime as compared to an existing geometry
  • The question arose whether the premature failure of the new design is directly connected to the change in the processing of the bow limbs
Solution:
  • Reverse engineering of an elasto-plastic DIGIMAT material model
  • Computation of 1st principles stresses for preload and load cases based on fiber orientation data coming from Moldflow
  • Life time prediction using a Haigh diagram
  • Comparison between the two different designs for the bow limbs
Results Validation:
"By using DIGIMAT we could clearly demonstrate the tight link between geometry, flow of material, fiber orientation and mechanical behavior. We successfully used the approach to evaluate the endurance of a number of different bow limb designs." Laurent Hazard, CAE Senior Specialist, SOLVAY
Benefits:
  • The lifetime in fatigue of the original design should be slightly longer than the new design
  • The higher stress level for the new design could be connected to a higher local stiffness in the critical region in the bow limb
  • The higher local stiffness could be explained by a “better” fiber orientation due to a change in the melt flow in the processing step (combination of two “converging” flows)

 
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