Company:

Comtes FHT

Products:

Marc

Industries:

Machinery

Marc Heat Transfer Analysis Helps Solve Tough Forging Problem

Challenge:

Pilsen Steel, a leading producer of castings, ingots and forgings experienced difficulties with ingots cracking in a forging operation. The company contracted with COMTES FHT to investigate and determine the root cause of the formation of longitudinal cracks in 34CrNiMo6 steel ingots.

Solution:

Traditional process involved cooling of the ingots after casting to between 500oC and 600oC, after which the ingots are placed in the forging furnace at temperature of 1100oC to 1200oC. COMTES used MSC Software’s Marc nonlinear finite element analysis (FEA) software to analyze the process of heating the ingots in the furnace and confirmed that heating the ingots in the furnace generated thermal stresses that later caused cracks to form during forging. Additional simulation studies also showed that increasing the temperature of the ingots by 100oC prior to putting them into the furnace reduced thermal stresses to acceptable levels. Pilsen Steel implemented this change and it eliminated the cracking problem.

Benefits:
  • Realistic Simulation of the Multiphysics behavior of metal during manufacturing
  • Elimination of cracking in final product reducing reject rate and improving product quality

Performing thermal analysis on the complete ingot workload requires determining the radiant heat transfer between the furnace and each of the each ingots with shading effects taken into account. Marc excels at this type of challenging multiphysics problem which is why it is our finite element analysis tool of choice

Tikal, COMTES FHT


 
DOWNLOAD

Company:

Medicrea

Products:

Digimat

Industries:

Medical Devices

Designing Spinal Disc Prosthesis Implants using Short Fiber Reinforced Composites

Overview:

Spinal injury and the gradual deterioration of spinal discs that lead to back pain or spinal disorders can be treated surgically. One of the most promising surgical options under continuous development is the use of artificial discs to replace the patient’s natural spinal disc. The materials used in these artificial discs are an important factor in the development of this technology. The discs must be made from materials that are safe to be implanted in the human body, do not cause allergic reactions, but also wear resistant and compatible with medical imaging (MRI for example). Fiber reinforced plastic composites are used more and more in today's orthopedic implants because of their resistance to wear and improved mechanical properties.

Challenge:

The challenge when designing implants that take advantage of reinforced plastics is predicting the manufactured material performance. The mechanical properties of an implant designed with fiber reinforced plastics can vary widely depending on the use of the material and how the implant is manufactured. The injection or compression molding process used to manufacture the implant will affect the fiber orientations throughout the part. Typical analysis assumes the material is isotropic for simplicity, but in reality the fiber alignment is continuously changing throughout the implant, resulting in a heterogeneous, anisotropic material. Poorly aligned fibers or not appropriately accounting for the fibers’ effect on material performance can lead to a softer or stiffer implant than designed, and even premature failure.

Solution:

MSC Software’s Digimat produces a much more accurate prediction of the composite behavior for materials such as fiber reinforced plastics. The process is simple. Start with the same finite element model of the implant that is used for the existing analysis. Digimat will work with any major finite element solver. Next, request the injection mold simulation results from the manufacturer. This analysis is done to assure the implant’s mold has been designed properly for manufacture, but the results can also be used in the finite element analysis of the implant itself. To do this, use Digimat to map the fiber orientations, residual temperatures and residual stresses onto the structural analysis model.

Select or create an intelligent material model of the reinforced plastic using the tools provided by Digimat. The intelligent material model is a function of fiber orientations instead of a static value, allowing Digimat to adjust the material stiffness at every location throughout the implant. Finally, conduct the analysis as normal with one exception, the static value for material stiffness will be replaced by a Digimat material model.

Digimat takes care of tying the intelligent material into the analysis solution so that the analyst can focus on designing the implant’s performance, not guessing at which material property might give the best results.

Results Validation:

The attention to material details result in much more accurate simulations that reduce test/ analysis iterations and improve performance predictions. In the case of the Medicrea design, the original isotropic simulation over-predicted the implant’s stiffness by as much as 170%.

The same simulation using a Digimat material model that accounted for both changes in fiber orientations as well as plastic deformations matched the test results almost perfectly.

Benefits:
  • Cost and time savings
  • Reduce test/analysis iterations
  • Improve performance predictions by 170%

 
DOWNLOAD

Company:

NASA (JWST-ISIM)

Products:

MSC Nastran
Patran

Industries:

Aerospace

Structural Analysis and Model Validation for the JWST ISIM Structure Using MSC Nastran

Overview:

The James Webb Space Telescope is a highly sensitive instrument that is positioned using a precise optical metering support structure. This supporting structure is made from composites to reduce thermal expansion effects while reducing weight. The instrument and structure are subjected to temperatures ranging from ambient during launch to cryogenic temperatures while in orbit. Dynamic and static loads are encountered during launch and in operation respectively.

Challenge:

The support structure must meet stringent structural requirements related to distortion, dynamic and static loading events. Testing must be supplemented by analysis to verify and improve the limited number of physical tests. Methodologies must be developed to explore the design via a probabilistic approach and satisfy performance within a 2-sigma range of uncertainty.

Solution:

A high fidelity MSC Nastran model (1.5 M nodes, ~5M DOF) was used to examine the structural integrity of the ISIM structure at the global level due to thermal and gravity loads (SOL 101) and a reduced Craig-Bampton model for dynamic analysis (SOL 103). Global only and global-local (detailed stress models) approaches were used along with testing as a basis to develop and validate methodologies and allowables for the design of composite joints.

The high fidelity MSC Nastran dynamic model was validated via subassembly testing and the results were used to determine optimal placement of instrumentation, excitation load point and target modes. The high fidelity MSC Nastran model was also used to predict the thermal distortion that occurs moving from ambient to cryogenic temperatures, cryogenic thermal stability and physical distortion from 1 G loading.

The model was also used to quantify error bounds and uncertainties due to material, manufacturing and spatial variability compared to a nominal analysis. The same model was used to determine and validate strength allowables via a semi empirical approach. These allowables included composite interlamina failure, composites n-plane failure and metallic ultimate and yield failure conditions at both ambient and cryogenic temperatures. In addition, the global-local approach was used to validate adhesive maximum principal stress failure allowables at cryogenic temperatures.

Results Validation:

Direct application of the MSC Nastran solver resulted in a validated design that agreed with dynamic test results with frequencies matching within 5%. Thermal distortion predictions were validated with cryogenic testing and the error bound associated with nominal predictions was established. Allowables validated by MSC Nastran models were shown to be conservative at predicting composite joint failure at ambient and cryogenic temperatures.

Benefits:
  • Accurately predict dynamic, distortion & strength performance of a composite structure at launch & in orbit
  • Close agreement to test results
  • Ability to accurately replicate the extreme environments in space

 
DOWNLOAD

Company:

CRC-ACS

Products:

Marc
MSC Nastran

Industries:

Aerospace

Accurately Solving Postbuckling Composite Stiffened Panels in Marc and MSC Nastran

Overview:

This paper outlines the CRC-ACS (Cooperative Research Centre for Advanced Composite Structures) contribution to a software code benchmarking exercise as part of the European Commission Project COCOMAT investigating composite postbuckling stiffened panels. Analysis was carried out using MSC Nastran (Nastran) solution sequences SOL 106 and SOL 600, Abaqus/Standard (Abaqus) and LS-Dyna, and compared to experimental data generated previously at the Technion, Israel and DLR, Germany.

The finite element (FE) analyses generally gave very good comparison up to initial postbuckling, with excellent predictions of stiffness, and mostly accurate representations of the initial postbuckling mode shape, leading to fair comparison in deep postbuckling. Accurate modeling of boundary conditions and panel imperfections were crucial to achieve accurate results, with boundary conditions in particular presenting the most critical problem.

Challenge:
Utilizing composite compression tests performed by the Israel Institute of Technology (Tension) and the Israel Aircraft Industries, a “state of the art” study was performed for composite buckling verification via Finite Element Analysis. Comparisons were completed for MSC Nastran SOL106, Marc (via Nastran SOL600), Abaqus and LSDyna.
Solution:

The particular panel selected was a fuselage-representative, 5-blade stiffened, curved panel. A summary of the panel specifications is given in Table 1, where the 0° direction is parallel to the stiffeners. The stiffener and skin are joined using a flange, where the stiffener plies are continued over the web, half on each side, and the flange outer plies are sequentially terminated 4 layers at a time, at increments of 10 mm.

The test panel was encased in potting on both ends to ensure a homogenous distribution of the applied displacement. Large plates were used on the panel sides, aligned with the tangent to the panel edge, to restrict radial displacements without adding constraint in the tangential direction. Panel skin imperfections were measured using an LVDT probe. The testing procedure involved loading the panel in compression up to a point where global buckling was seen in a moiré fringe pattern, then unloading. This was repeated twice, before the moiré fringe was removed and the panel loaded to collapse.

Results Validation:

The structural stiffness and buckling load were predicted well, though all models slightly under-predicted the buckling point by a maximum of 11%. The strain data gave less acceptable correlations, while the pre-buckling and initial postbuckling predicted moderately well, leading to poor correlations in deep postbuckling. Panel failure was not captured by either solution sequence, though Marc has the capacity to monitor various failure criteria.

Comparatively, the two Nastran solution sequences gave very similar behavior for most results, with only strain values data showing significant discrepancies. The axial shortening of both solution sequences did show slight discrepancies, especially in the deep postbuckling region. The SOL 600 (Marc) solution gave higher stiffness, seen in a slightly higher global buckling load, and a slightly different stiffness in the deep postbuckling region. The deformation pattern and displacement of various points around the panel showed close agreement, with only small variations in the deep postbuckling region.

Benefits:
• Accurately predict performance of panels before buckling and even with post buckled performance
• Close agreement to experimental data
• By utilizing accurate simulation, millions of dollars can be saved on a single new aircraft program

 
DOWNLOAD

Company:

The Hadley Group

Products:

Marc

Industries:

Machinery

Simulation Increases Sales $4 Million by Validating New Cold Roll Forming Process for Customer Applications

Overview:

Hadley Industries PLC’s core business is manufacturing cold roll formed products, primarily to the building and construction industries. The company developed and patented a unique cold forming process known as UltraSTEEL® which significantly improves mechanical and structural properties of the strip steel by imparting a dimpling pattern prior to the roll forming operation. The geometry is much too complex to determine the structural properties of the end product based on analytical calculations alone, and it could cost $30,000 to $150,000 for tooling to manufacture the part so its properties could be physically measured.

Challenge:

Hadley addressed this challenge by using Marc nonlinear finite element analysis software to predict the highly nonlinear changes in geometry and material properties that occur during the UltraSTEEL® process, cold roll forming and secondary processes. “Marc overcame problems seen with other finite element software packages such as nonconvergence and provided reliable and consistent results that matched experimental measurements,” said Dr Martin English, Design and Development Manager for Hadley. “The ability to accurately simulate the process and quickly determine its performance in customer applications has been responsible for a substantial increase in sales volume estimated to total over $4 million over the next three years.”

Solution:

Complex and interrelated nonlinear changes in contact, geometry and material properties occur during the UltraSTEEL® process and subsequent section forming and secondary operations. “The simulation challenge involves both accurately simulating these processes as well as applications under loading,” Nguyen said. “This requires simulations that connect to previous or subsequent simulations to perform continuous processes while taking into account the changes in geometry, material and structural properties of the materials. An important advantage of Marc in this regard is its PRE STATE procedure which can be used to transfer the geometry of the dimpled strip together with its material data including stress/strain data generated from the dimpling process into the subsequent simulations such as the cold roll forming process.”

The ideal approach is to simulate the entire chain of processes as a sequence from start to finish: 1) the dimpling process that deforms a flat steel strip into a dimpled strip, 2) the cold roll forming process that produces the desired section, and 3) additional processes such as shear cutting and applications such as products under tension, bending, compression loads, etc. The geometry and material data of the dimpled strip are transferred from one process to the next in a closed loop. This approach is practical for small sections of dimpled products and optimizing the dimpling process itself. However, the models of the rolls and dimpled strip can contain tens of millions of elements for larger models so transferring the stress/strain data between each of the stages becomes very complicate and time-consuming, resulting in high computational costs.


Results Validation:

“The reliable and consistent results provided by Marc make it possible to accurately assess the applicability of UltraSTEEL® for existing and new products in a short time frame at a low cost,” English concluded. “The accurate simulations have enabled Hadley to make and substantiate technical claims regarding the benefits of the process. As a result the company has increased its sales of UltraSTEEL® products and also generated additional revenue by increasing licensing of the process amounting to an estimated $4 million over the next three years.”

Benefits:
  • Reliable, consistent results that matched experimental measurements
  • Reduced physical prototyping for product development cost savings
  • Higher accuracy by accounting for forming induced residual stresses in product testing

 
DOWNLOAD

Company:

Airbus

Products:

Actran TM

Industries:

Aerospace

Simulation Helps Airbus Optimize Acoustic Liners and Reduce Noise

Overview:

Noise is becoming a major obstacle to growth in air transport as increasing numbers of airports place restrictions on the amount of noise that can be generated by an aircraft during various phases of flight. Airbus is working hard to reduce aircraft noise such as by improving the nacelle acoustic liners used to minimize the fan noise radiated from the engine. The company has dramatically reduced the time required to design and evaluate optimized acoustic liners by moving to a simulation-based process using Actran acoustic simulation software developed by Free Field Technologies (FFT), MSC Software Company.

Challenge:

The acoustic liners that are built into the engine nacelle are fundamental in controlling fan noise. Acoustic liners present a major design challenge because they must address a large number of conflicting design requirements. Liners must provide high levels of noise reduction over a wide range of engine operating conditions and frequencies. Liners must also meet tight space restrictions and need to be as light as possible in order to limit fuel consumption. The liner is typically designed at a point when aspects of the airframe and engine are not completely defined so the liner design must be flexible enough to adapt to changes. The liner must be able to survive exposure to heat, cold, water, oil, and maintenance operations. Finally, the liner must be durable enough to deliver decades of service in the highly demanding aircraft engine environment.

Solution:

Liners are typically manufactured in two or three curved segments that are assembled with longitudinal splices. Simulation with Actran and other numerical tools helped to reveal the substantial impact of splices on forward fan noise and these simulations were confirmed with physical testing. These simulations made it possible to compute the radiated noise fields under all relevant engine operating conditions and predict the noise reduction in certification conditions. The design of the zero-splice concept, through numerical simulation, made it possible to significantly reduce the fan noise and the acoustic discomfort.

Results Validation:

Airbus developed an integrated numerical chain for Actran in order to streamline its use by acoustics engineers who are not numerical experts. The chain, called Automated Liner Optimization Chain for Nacelles Air Inlets and Exhausts (ANaNax), automates the simulation process from engine geometry to Actran results including prompting the user for all required information and performing validation checks on the data entered by users. “A typical optimization loop for the nacelle liner requires evaluation of 80 liner iterations and three flight conditions at a frequency range from 125 Hz to 5650 Hz which means we need to simulate several thousand different cases,” Suratteau said. “Robustness and accuracy of the simulations is critical so realistic 3D shapes, flows and boundary conditions are a must. ANaNax greatly reduces the time required for non- analytical experts to perform simulations and to check their work to be sure inputs are realistic. Computation time has also been drastically decreased by the implementation of a high performance computing (HPC) platform based on Westmere X5670 Infiniband technology with 5312 cores combined with the high scalability of Actran.

Benefits:
  • Reduce product development costs by avoiding expensive post-design changes.
  • Reduce test/analysis iterations
  • Improve performance predictions

 
DOWNLOAD

Company:

IDEA International

Products:

MSC Nastran
Patran

Industries:

Shipbuilding

IDEA International - Explicit Analysis of Tsunami Survival Capsule

Overview:
In order to ensure that the capsule can withstand the harsh environment of a tsunami, IDEA engineers are using MSC’s simulation technology. “The use of MSC Nastran and Patran allows us to understand the performance of the capsule and reduce the test program substantially,” said Scott Hill, IDEA Engineering Director of IDEA, Inc. “Also, the analytical simulation results that MSC Nastran and Patran provides, allows us to greatly understand the structure and predict eventualities which may cause issues during a Tsunami event. As a result we can remove these issues during the design phase.”

Benefits:
  • Greater understanding of structural damage due to a variety of large impact events.
  • Less physical testing and prototypes due to accuracy of simulation.
  • Increased safety of vessel.
For more information please watch the Tsunami Survival Capsule Video.

 

Company:

Scania

Products:

Adams

Industries:

Automotive

Scania - Improving Heavy Truck Designs

Overview:
Scania uses simulation to evaluate a much greater number of vehicle configurations than was possible in the past. “We selected MSC Adams/Car because Adams provides the premier solver technology and has become the de fact standard in the automotive industry..MSC Adams/Car supports Scania’s modular vehicle configuration strategy by enabling us to model and simulate different vehicle configurations in a small fraction of time that would be required to build and test them.”
Benefits:
  • Significantly improve the handling, comfort and fatigue life of vehicles
  • Reduced stress levels in many parts, resulting in improvements in component life
  • Identify potential problems early in the design process and make corrections on the virtual model

 
DOWNLOAD

Company:

Knud E. Hansen

Products:

Adams

Industries:

Shipbuilding

Knud E. Hansen A/S - Safe Marine Operations in Wind Energy

Overview:
The Anholt Offshore Wind Farm is a Danish wind farm currently under construction, located in Kattegat, between Djursland and Anholt Island. Knud E. Hansen was contracted by MT Højgaard A/S to assess the Drill Rig’s waves induced motion while transported by HLV SVANEN, and to calculate the maximum tensions on the lashing cables for a maximum operational wave height.

“Adams Software helped us to understand the motion and forces involved by capturing the full gamut of real world complexities including rigid bodies, flexible bodies, springs, dampers, joints and all others mechanical components. The software never placed any limits on what I wanted simulated, yet it made it possible to assemble the complex model very quickly. ”

Mirco Zoia, Navel Architect & Offshore Eng., Knud E. Hansen A/S

Challenge:
Accurate assessment of complex mechanical systems that require a dynamic analysis
Solution:
Initially, the 3D Multi-body Dynamic model of the system composed by HLV SVANEN, the Drill Rig and its crane lifting components (Lifting Spreaders, Lifting and Lashing Equipment), was created in a CAD software and then imported to Adams. Densities and other material properties were given to the parts of the 3D Model. All the parts in motion were joined together with translation, revolving, spherical and cylindrical joints to simulate as close as possible the real behaviour of the system. The steel and fibre ropes of the system were defined as flexible dynamic bodies with the same material properties (density, young’s modulus, poisson’s ratio, and damping coefficient) as the actual ropes. The winch pretensions were defined using preloaded spring-dampers. Motions, constraints, wind forces and winch pretension loads were then applied to HLV SVANEN. The motion analysis was based on the HLV SVANEN maximum response motion previously assessed.

The dynamic analysis was carried out to assess the maximum displacement of the Drill Rig, and the minimum required winch pulling force to fulfill the requirements of the client and to safely carry out the necessary marine operations.
Benefits:
  • Ensure the safety of the marine operations
  • Reduce risks and costs of the wind turbines installation
  • Anholt offshore windfarm to become the biggest offshore windfarm in Denmark

 
DOWNLOAD

Company:

BioSimulations, LLC

Products:

Marc

Industries:

Medical Devices

BioSimulations, LLC - Simulation of a Molded Elastomeric Helical Anchor Nerve Clamp

Overview:
The ability to control, modify or block the signals from the receptors to the brain may be accomplished through selective electrical stimulation of a specific nerve path. MSC Software’s Marc nonlinear simulation solution was selected to generate the model, perform the analysis and post-process the results.
Challenge:
To evaluate a proposed design concept for an electro-mechanical device
Benefits:
  • Successfully check the model components and generate a final assembly of the model.
  • Performed model pull-off loading using incrementally applied large displacements.
  • Make results plotting easy using Marc post-processing features.

 
DOWNLOAD

Company:

Fokker Aerostructures

Products:

MSC Nastran
SimXpert

Industries:

Aerospace

In Summa Innovation & Fokker Aerostructures - New Methods for Simulation Automation

Overview:
In May 2011, MSC Software, In Summa Innovation, and Fokker Aerostructures entered into a close partnership. In the so-called “Fokker Virtual Lab” the three companies started to do serious research with MSC Software products SimXpert and MSC Nastran.

The goal of this first project was twofold:

1) Familiarization and testing of MSC Nastran

2) Familiarization with SimXpert to create a prototype for a process to automate the creation of a QA-sheet, the quality assurance of FEM models.
Challenge:
Investigate new simulation technologies for future use.
Benefits:
  • Created a prototype for a process to automate the creation of a QA-Sheet.
  • Researched new technologies in a joint effort between suppliers and users.
  • Developed the process of how to use SimXpert & MSC Nastran in the complete design process outside the production environment.
  • 50% reduction in report generation
  • Identification and reduction of errors

 
DOWNLOAD

Company:

Schindler

Products:

MSC Nastran
SimXpert

Industries:

Machinery

Schindler - The Ups and Downs of Finite Elements

Overview:
Schindler is a concern with business activities in all five continents and a market leader in the lift and escalator sector. Schindler’s offering ranges from passenger lifts suitable for small blocks of flats to sophisticated transport solutions for skyscrapers. Service lifts ensure the stress-free movement of goods and people in shopping centres, office buildings and railway stations. Bed lifts provide for the smooth and vibration-free movement of patients and equipment in hospitals. In industrial buildings, many of the hoists and small goods lifts in use are supplied by Schindler, while glass cabin lifts in tall buildings offer both a novel experience and a feeling of safety.
Challenge:
Find reliable & energy efficent solutions which make the optimum use of materials for complete lift systems
Benefits:
  • Simulate wall fixings of lifts and determine whether deformations and loadings remain within the permissable range
  • Model and evaluate a greater number of design variants using automated processes
  • Carry out static (strength) calculations, dynamic and vibration analyses with the aid of FE methods.
  • Construct consistent model

 
DOWNLOAD

Company:

TLG Aerospace, LLC

Products:

MSC Nastran
MSC Nastran Desktop
Patran

Industries:

Aerospace

TLG - Making Better Aircraft Everyday

Overview:
TLG Aerospace, LLC (TLG) is an aerospace engineering services company founded in 2008 in Seattle, Washington. TLG, ‘The Loads Group’ specializes in full vehicle analysis and optimization including static and dynamic loads, flutter, stability and control, aerodynamic design, Computational Fluid Dynamics (CFD) analysis, FAA certification and aircraft performance and handling qualities. TLG provides design, analysis and certification for new and modified aircraft and related aerospace products.

TLG’s primary customers are OEMs, thirdparty modifiers, and other companies who design, analyze, build and sell aircraft, aircraft modifications, and related products. TLG’s focus is on helping these customers get those products to the marketplace and in service as efficiently as possible. TLG routinely works with hardware-related groups such as manufacturing and test organizations. TLG engineers specify flight test instrumentation requirements and test conditions, act as engineering test crew for test flights, and prepare flight test reports within their disciplines.TLG also provides overflow capability for OEMs needing extra capacity, and helps new aircraft companies develop and validate their own loads and dynamics capabilities. TLG engineers have analytical and hands-on experience with over 100 aircraft models from more than 40 different manufacturers.
Challenge:
Determine design loads by involving a full aircraft analysis of the air pressure and inertia forces during prescribed maneuvers, either in the air or on the ground.
Benefits:
  • Faster design iterations
  • Efficient use of capabilities for aeroelastic analysis is used in all parts of the design process
  • More efficient aircraft design & analysis

 
DOWNLOAD

Company:

DEMA

Products:

MSC Nastran

Industries:

Aerospace

DEMA - Stamping Out Waste

Overview:

Design Manufacturing SpA (DEMA) is a major tier-one aerospace supplier to Bombardier, Alenia Aermacchi, AgustaWestland and other leading aerospace original equipment manufacturers. The company recently faced a challenge with an aluminum acoustic barrier which is part of a jet engine nacelle. DEMA performed finite element analysis (FEA) with the MSC Nastran implicit nonlinear solver which identified two problems in the initial design. These included a stress concentration around a radius and excess material beyond the dimensions of the finished part which would have required an expensive secondary operation.

Challenge:
  • Maintaining allowable stress concentrations during metal stamping procedure
  • Reducing expensive secondary operations
Benefits:
  • Reduced prototyping and manufacturing costs
  • Substantial reductions in design time

 
DOWNLOAD

Company:

University of Cassino

Products:

Dytran

Industries:

Medical Devices

Understanding Eye Injuries as a result of Blunt Impact Trauma

Overview:
The detachment or tearing of the retina in the human eye as a result of a collision is a phenomenon that occurs very often. The project was aimed at understanding the actual processes of dynamic deformation taking place in the human eye when subjected to blunt impact. For this project an FEA model was developed in MSC’s Dytran software starting from 3D measurements of real human eyes. The results of the model were then compared to measurements with respect to the deformation at different times and to the residual velocity of the projectile during the rebound phase.

Challenge:
  • Over 60% of all eye injuries are caused by blunt impact, i.e. impacts with objects of various kinds that do not cause a perforation of the globe.
  • Based on evidence of a patient who, despite having undergone the removal of the vitreous, had a clear macular hole resulting from a blunt impact, it was decided to investigate this phenomenon in more detail in order to validate the various hypotheses of damaging mechanism with the help of a MSC Dytran simulation.
Solution:
  • The computational model of the ocular globe was generated starting from an average size human eye represented with the help of the code MSC Dytran.
  • The preliminary results of the project indicate that the laceration of the retina mainly occurs due to the tension resulting from the reflection of compression waves in the moments immediately following the impact, and not necessarily due to the deformation of the whole eye.
Benefits:
  • The availability of a reliable and validated model for the simulation enabled the research team to understand in detail the pathogenesis of the blunt impact phenomenon, which is particularly difficult to reproduce in a controlled and instrumented manner through physical tests in the laboratory.
  • Practical applications of this study are to be found especially in the military industry, for example in the design of advanced security systems for personnel and for helicopter pilots in the event of a crash landing.

 
DOWNLOAD

Pages