Company:

Parker Hannifin

Products:

Marc

Industries:

Energie

MSC's Marc Helps Ensure Safe Operation of Subsea Oil Drilling

Overview:

In designing heavy machinery, such as those on cranes or oil rigs, small plastic components or rubber seals can be vital to the integrity of those large structures. Stephen Armstrong an FEA Analyst/New Product Development Engineer and his team at Parker Hannifin Corporation work on designing just these types of parts.

Parker Hannifin is a trusted leader in motion and control technologies. Stephen’s team’s main area of focus is on seals that are comprised of hyperelastic materials such as rubber, polyurethane, and other compounds. These seals are used in a variety of applications in heavy machinery, medical devices, military and aerospace industries.

Engineers working with these materials focus on nonlinear analysis in most of their projects, because these materials mainly exhibit non-linear behavior. MSC’s Marc was their tool of choice for simulating such behaviors.

Benefits:

Enhance the seal design and reduced physical testing


 
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Company:

Renault

Products:

Actran Acoustics

Industries:

Automobile

MSC Software Helps Renault Reduce Pass-by Noise

Overview:

In recent years, there has been a global initiative to reduce traffic noise and improve comfort in automotive vehicles. Engineers have to meet stringent government regulations while still improving the passengers’ experience. One requirement involves a measurement procedure commonly referred to as Pass-by Noise. The maximum allowed sound level for Pass-by Noise has recently been reduced, now representing a new constraint on the design of commercial vehicles. Countermeasures to reduce noise emissions consist in moderating the different acoustic sources by either acting on the noise generating mechanisms or managing the noise propagation. Adding sound absorbing materials or modifying parts of the vehicle geometry are solutions that engineers are investigating to solve this problem. With its wide range of vehicles, the Renault team has to anticipate the evolution of Pass-by noise regulations and design vehicles according to future constraints. Renault decided to extend its acoustic simulation capabilities and model the exterior acoustic propagation using Actran, a product of FFT, an MSC Software Company. With Actran, Renault was able to improve their designs and reduce development costs by considering the vehicle acoustics early in the design phase.

Results Validation:

When studying Pass-by noise, it is essential to make sure that the numerical simulation is accurate. The absolute sound level recorded during the test determines if the vehicle will pass or if it will be rejected. “We had some measurements from physical testing available when we started the validation,” Philippe explains.

“When we started the project we were quite far, we needed to analyze the results and understand the problems in the way we were modelling. Now we are quite happy with the results. We went quite fast in improving the accuracy.” Following this successful validation phase, the methodology is now used daily by Renault engineers to optimize the technical definition of the vehicle to be sure that absorbing materials will be placed exactly where needed. “Compared to the initial target, we achieved much better performances. We started from scratch for this exterior acoustic problem, and what we were able to achieve in just a couple of years in this project is quite impressive to me” concludes Philippe.

Benefits:

Reducing development costs by integrating acoustic constraints at early stages through simulation.


 
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Company:

Stratasys

Products:

Digimat

Industries:

Additive Manufacturing

Simulating effects of warpage in an additively manufactured composite layup tool

Overview:

For more than 25 years, Stratasys has been a defining force and dominant player in additive manufacturing – notably inventing the Fused Deposition Modeling (FDM) Technology. The company’s solutions provide customers with unmatched design freedom and manufacturing flexibility – reducing time-to-market and lowering development and manufacturing costs.

FDM® (fused deposition modeling) is becoming the technology of choice for rapid production of high-temperature (> 177 ° C), low-volume, composite lay-up and repair tools, as well as for moderate-temperature (<163 °C) production sacrificial tooling. Relative to traditional tooling materials and methods, FDM offers significant advantages in terms of lead time, tool cost and simplification of tool design, fabrication and use, while enabling increased functionality and geometric complexity.

Benefits:
  • Print it right the first time!
    Iterate designs and parameters through simulation rather than wasting time and materials with iterating through printing
  • Save time & material!
    Anticipate printing issue with simulation (e.g., evaluate the impact of the printing direction and location on results)
  • Minimize warpage in only two steps!
    Thanks to a predeformed geometry
  • Optimize the manufacturing process!
    Quickly explore at virtually zero marginal cost the sensitivity of process parameters on the process quality and part fidelity
  • Access to an easy, efficient and user-friendly GUI!
    Designed to follow the printing workflow and accessible for non FEA experts

 
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Company:

TEN TECH LLC

Products:

MSC Apex
MSC Nastran
MSC One

Industries:

Aéronautique & Défense

MSC One Provides TEN TECH LLC Access to MSC's Complete CAE Platform

Overview:

MSC Software pioneered many of the technologies that are now relied upon by the Aerospace industry to analyze and predict stress and strain, vibration & dynamics, acoustics, and thermal analysis in their flagship product, MSC Nastran. Similarly, MSC Marc and MSC Adams are highly regarded as industry-leading applications for non-linear simulation and kinematics, respectively.

TEN TECH LLC, a Los Angeles based engineering consulting firm, conducts complex engineering Finite Element Analysis. As subject matter experts in shock, vibration and thermal analysis for the Aerospace & Defense Industry, TEN TECH LLC relies heavily on MSC solutions. The types of products and applications TEN TECH is involved with share a common characteristic: field failure is never an option. To validate these designs, complex multi-physics analyses and high-performance solvers that provide great accuracy are required. TEN TECH LLC being a Small Business, high-end CAE software procurement is always a delicate balancing act as high performance and accuracy comes at a hefty premium. At least it did until now: enter MSC One.

MSC One is an expanded products token system that allows companies to take advantage of the breadth and depth of MSC Software’s simulation portfolio within a flexible token-based licensing system. Offered on an annual subscription basis, MSC One provides efficient implementation and access to a suite of multidisciplinary engineering software tools.

For TEN TECH LLC, the ability to easily access the extensive MSC One product portfolio, including all of MSC’s core products such as MSC Nastran, Adams and Marc, but also Sinda and SC/Tetra for thermal and CFD analysis was an easy choice. Access to such a variety of tools through a “check-in, check-out” token system, allows the team at TEN TECH to solve a multitude of their clients’ vibration, non-linear, thermal and CFD problems for a fraction of the cost typically incurred.

Recently, TEN TECH LLC’s Structural Mechanics Group has been actively involved in the development of telescope structures, providing Finite Element Analysis expertise for the design validation of the telescope structure supporting the Polarization of Background Radiation telescope array experiment (POLARBEAR-2).

Funded by the Simons Foundation, POLARBEAR-2 is an international collaborative effort including 8 countries, and 20 institutions. Based in Chile’s Atacama Desert, the Simons Array, comprised of three polarization of background radiation telescopes, will probe the skies in search of proof of inflation, the hypothetical moment following the Big Bang.

“We heavily relied on MSC Apex and MSC Nastran to perform these complex structural analysis tasks. MSC One made our life much easier than with our traditional workflow” - William Villers, CTO & Director of Engineering at TEN TECH LLC.

Results Validation:

The TEN TECH team was able to quickly mesh and run FEA on a very large and detailed model of a complex assembly, starting from native CAD files. Apex allowed the team to proceed with incremental analyses of subassemblies and build a very large and complex model “right the first time”. With Apex, the engineers shortened their “CAD to FEM to Analysis” time by 25%-30% compared to their traditional workflow process. At the same time, they delivered a high fidelity, reliable model to their client.

MSC Nastran’s high performance was highlighted throughout the entire project: through its ultra-fast iterative solver and GPU-accelerated processing for linear statics, to Automated Component Modal Synthesis (ACMS) and Distributed Memory Parallel (DMP) solver for large dynamics problems, MSC Nastran performed flawlessly and delivered the highly accurate results required to achieve the proper confidence level in the design.

TEN TECH plans to further utilize MSC’s products through MSC One, including Sinda, Adams, and MSC Nastran. The price of MSC One gives the TEN TECH team the financial freedom they need to use MSC Nastran and other products.

Benefits:

Increased productivity by utilizing MSC Apex Fossa to save time during the design process


 
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Company:

Scania

Products:

Actran Acoustics
MSC Nastran

Industries:

Automobile

MSC Software helps Scania Reduce Cabin Noise in Trucks

Overview:

Having a pleasant driving experience is a key determinant when purchasing or driving a vehicle. For companies buying trucks and for truck drivers, it is also a matter of health and productivity. Most drivers spend more than 8 hours a day in the truck cabin. High noise levels or unpleasant sounds in a working environment are known to cause excessive fatigue and health problems. It is therefore crucial for truck manufacturers to carefully design their new products and shape the cabin noise to go beyond the requirements of their customers, and propose the most enjoyable driving experience possible.

With a wide range of premium trucks, Scania, one of the world’s leading truck manufacturers naturally aims at designing trucks with outstanding comfort and performance. Scania’s Complete Vehicle Acoustic Department is focused on getting their vehicles up to speed with today’s drivers’ expectations by addressing the level and quality of cabin noise in their vehicles. The development for more optimized cabins is supported by extensive testing and the introduction of new methods based on vibro-acoustic simulations. For this endeavor, Scania’s development team chose to use Actran, a product of FFT, an MSC Software Company, to improve their designs and shorten their design cycles.

Results Validation:

Scania aims to increasingly utilize Actran’s simulations results to compare different designs and define the design directions early in the product development cycle, without the need for physical testing. To support this decision-making process, a listening studio was built at Scania. The studio is similar to that of a professional mixing studio. It encompasses a 7.1 surround system for sound and is designed to produce exactly the same listening experience for anyone who is seated in the center of the room. During subjective evaluation sessions, Per-Olof conveys to his fellow colleagues his findings based on his simulations. He combines test and simulation data to replicate the environment of driving an actual truck. This process helps managers to make important decisions, which will affect the design of the cabin. “It is a very different response from management when you can play a sound and they can have this subjective experience,” Per-Olof said. “It’s not really possible to understand from a graph what you will hear in the truck,” he explained.

With the use of Actran in this new simulation process and the subjective evaluations allowed by the listening studio, Scania now has all the tools needed to improve its customer driving experience even further, while having a more efficient design process.

Benefits:

Enhancing the design of the truck to prevent the negative effects of Cabin Noise


 
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Company:

Giant Magellan Telescope

Products:

MSC Apex

Industries:

Aéronautique & Défense

MSC Software Helps Giant Magellan Telescope Discover the Universe

Overview:

Where did our universe come from? Since the beginning of time, astronomers and physicists such as Galileo, Copernicus, and Einstein have dedicated their life’s work to this timeless question. Even today, investigating the universe’s origins remains hotly debated. To help answer this, the team at the Giant Magellan Telescope is building a 200 foot-high telescope that will help scientists uncover what has plagued scientists and science fiction enthusiasts alike: Are we alone? How did the first galaxies form? What is the fate of the universe? The GMT is uniquely poised to answer these questions due to its ability to collect more light than other telescopes and to its’ uniquely high resolution (which will be the highest ever achieved in a telescope). The project is sponsored by Astronomy Australia Limited, Carnegie Observatories, Harvard University, and other leading universities and research institutions from around the globe. Due to the complexity of the structure, placement of mirrors, and movements that will occur during operation of the telescope, the engineering team at GMTO used MSC Software’s simulation tool, MSC Apex, to simplify and shorten their design and simulation workflow.

Results Validation:

MSC Apex’s dynamic components for design, specifically its importing utility and meshing features, were instrumental in the design and analysis of the GMT. The software was essential in helping to identify particular wind dynamics issues during the design process, which allowed developers to save time and increase productivity. MSC Apex became a critical tool in the GMT’s design process due to its easy user interface and customized meshing and simulation features. With the aid of MSC Apex, engineers at GMTO will be able to answer some of the toughest questions faced by mankind in a more streamlined, efficient way than ever before.

Benefits:

Increased productivity by utilizing MSC Apex Fossa to save time during the design process


 
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Company:

Kyusyu Sangyo University

Products:

Adams

Industries:

Equipements industriels

Adams Simulation Incorporated DOE to Help Design Robot with Human Motion

Overview:

One of the most prominent areas of focus in the robotics industry today is the design of more human-like robots. Giving human features to robots offers tremendous advantages compared to traditional designs; for example, some robots are now designed with human-like legs rather than wheels, which enables them to move more easily in dangerous environments and over obstacles.

Results Validation:

“Prototypes of the ADDAM robot and the robotic arm were built and performed as predicted by the simulation with a high degree of fidelity. The ADDAM robot demonstrated human-like walking capabilities and met all of our other design objectives. The robotic arm can lift an object greater than 5 kg even though its own mass is only 2.2 kg.” - YongKwun Lee, Professor in the Department of Biorobotics in Kyusyu Sangyo University.

Researchers are planning to improve on the design of ADDAM by using multibody simulation to further improve the capabilities of ADDAM, such as by enabling it to perform fast walking, running, jumping, turning, and lifting heavy weights.

Benefits:
  • Adams simulation results achieved good correlation with physical measurements
  • Design of Experiments was applied on the robot model to optimize each design parameter using Adams
  • Prototypes of the ADDAM robot and the robotic arm were built and performed as predicted by the simulation with a high degree of fidelity

 
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Company:

Sant Longowal Institute of Engineering & Technology

Products:

Marc

Industries:

Aéronautique & Défense
Automobile
Equipements industriels
Transport
Construction navale

Marc Helps Solve Complex Welding Problem to Improve Life of Heat Exchangers

Overview:

Welding is a common practice in the automotive, aerospace, railways, ship building, and machinery industries. It allows for the joining of components by subjecting them to intense localized heat which melts and coalesces the material in the welded region, forming a permanent joint. Multiple process parameters influence the effectiveness of the welding, which include energy source, shape and size of the melt zone, heat affected zone, and speed. Understanding and improving this challenging process through physical iteration can be time consuming and expensive. MSC’s Marc, a nonlinear finite element analysis tool, can provide the required insights needed to solve these parameters in a cost-effective manner.

Results Validation:

The model demonstrated the effects of thermal contact at the joint interface during GTAW welding of the dissimilar materials, and the influence of transverse offsetting of the arc away from the weld line. “We found Marc to be very good in simulating the complex physics of the welding problems. Matching results with experimental data demonstrated that this approach can be used to significant costs by reducing material waste and improving life of the welded parts,” says Singh.

Benefits:
  • Easily try alternative approaches without having to invest in physical experimentation
  • Gain greater insight into temperature gradients with simulation, which are harder to measure in physical tests

 
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Company:

University of Missouri

Products:

Adams

Industries:

Biomédical

Adams Simulations Help Diagnose Knee Problems

Overview:

Mankind has explored the galaxies, the depths of the sea, and looked back millions of years into the past. But, there are still some surprisingly large gaps in our understanding of the human body and how it works. For example, the knee joint is at the center of the kinetic chain running from the foot to the pelvis. But the connection between the tibia and femur provides very little geometric constraint. Knee stability is achieved through the operation of a multitude of soft tissue structures. The details of how these structures work are still largely a mystery. MSC’s Adams, a multibody dynamics simulation solution, can provide the right insights to help get a better understanding of the inner workings of the knee.

Results Validation:

With the use of Adams, MAC researchers have begun to take the steps to grasp the complexity of the menisci function in the knee. They found that increasing the ligament length by about 20% will result in almost a complete loss of force transfer through the menisci during walking. The reduction in the forces absorbed by the menisci increases the forces that were directly transmitted between the tibia and femur, increasing the potential for joint damage and pain. These results will enable researchers and physicians to target and prevent future pain and damage more efficiently than ever before.

Benefits:
  • Predicts ground reaction forces with over 90% correlation to physical results
  • Accurately predicts internal contact forces
  • Determines effect of slack in menisci

 
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Company:

GE Tidal Turbines

Products:

Adams
Adams/Machinery
MSC Nastran

Industries:

Energie

Adams Simulation Helps Reduce Need for Physical Testing of Tidal Turbines

Overview:

There are many coastal areas where local geography constrains the movement of ocean tides, resulting in very strong currents. Water is 800 times denser than air so these currents could potentially generate a lot of electricity. GE tidal turbine technology brings proven concepts and industry-leading knowledge to tap into this reliable and predictable energy source. The Oceade* tidal turbine features a buoyant nacelle that enables the turbine to be easily towed to and from the operating site. This eliminates the need for specialist vessels, reducing the cost of installation and maintenance. GE has proven its Oceade* turbine operating at a full 1 Megawatt, injecting over 1.2 GWh of electricity to the grid. This test program has enabled GE to validate the installation and retrieval processes, autonomous running, and the performance and power curve of the new turbine.

Results Validation:

The simulation results provided the information to evaluate the dynamic response of the proposed design prior to investing in a physical prototype and testing. Based on the results, GE design assumptions and margins were verified and opportunities for optimization identified. The company is now moving forward to the testing phase confident that the design has been “de-risked” from a dynamic as well as a kinematic standpoint. “This project was a great working experience that allowed the GE team and MSC consultants to share knowledge and gain experience from their own respective expertise,” concluded Valentin Radigois, Lead Engineer, Mechanical- Components, GE Renewable Energy.

Benefits:
  • Predict the dynamic behavior of the turbine including multiple flexible components
  • Integrate real bearing and gear effect including 3D contacts
  • Simulate various dynamic loads to evaluate complex behaviors and coupling effects
  • Performed modal analysis of the full structure

 
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Company:

Tower International

Products:

Marc

Industries:

Automobile

Automotive Supplier Uses Marc to Improve Design of Stamping Tools

Overview:

Stamping operations used to form metallic automotive components can generate forces of thousands of tons. The tools (die components) that form these products must be able to withstand this cyclic loading environment for the life of the vehicle program. At the same time, it is important to optimize the tool design in order to be competitive. The evolution of higher strength materials also adds to the challenge. The large loads involved in forming these components increase the challenge of designing robust tools. Both linear and non-linear analysis must be used to support the tool design process.

Results Validation:

“In order to get reliable predictions, we prefer to use the nonlinear software Marc to solve these types of problems because it accounts for the inherent nonlinearities of materials experiencing plastic strain,” said Yueming Cheng, Computer Aided Engineering Engineer at Tower International. “In years of using Marc and Mentat, I have found it to be capable of accurately simulating a wide range of nonlinear product behavior under static, dynamic and multi-physics loading scenarios. Marc is also one of the commercial solutions in markets I am aware of that has robust manufacturing simulation capabilities, with the ability to predict general damage, failure and crack propagation.”

Benefits:
  • Accurate simulations help reduce risk of downtime and lost revenues, by predicting regions of potential failure
  • Get the design right the first time with computer models and deliver reliable performance

 
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Company:

Shanghai Jiao Tong University

Products:

Adams

Industries:

Equipements industriels

Chinese University Develops Legged Robot for Rescue Operations in Nuclear Plants

Overview:

Shanghai Jiao Tong University researchers including Dr. Gao Feng, Director of the Chinese National Laboratory of Mechanical System and Vibration at SJTU and Dr. Yang Pan, Postdoctoral Research Fellow at SJTU, have designed the Octopus III six-legged robot for moving, searching, detecting, repairing and rescuing in extreme environments such as nuclear radiation, fires, and underwater. The six-legged Octopus III robot takes advantage of the unusual capabilities of legged robots such as traversing uneven terrain, overcoming obstacles, performing vertical climbs, and righting themselves after turning over.

Legged robots are substantially more difficult to design than wheeled robots because they require complex mechanics and control strategies to maintain their equilibrium, orientation, efficiency and speed. The Octopus III’s six legs each have an identical drive mechanism consisting a parallel mechanism with three limbs. Each leg has one UP limb with a universal joint and a prismatic joint connected in series and two UPS limbs with a universal joint, a prismatic joint and spherical joint connected in series.

The robot is controlled by an onboard computer running the Linux operating system that communicates wirelessly with a remote computer running the Windows operating system. Orders such as move forward or turn left can be issued to the robot through a human machine interface (HMI) on the Windows computer. The onboard computer contains optimized kinematics and dynamic models of the robot and controls the robot’s 180 servo motors. The robot weighs about 270 kg, can climb a 20 degree slope and walks at 1.08 km/hr.

Results Validation:

The SJTU researchers tested the prototype under a wide range of conditions such as turning valves and switches and carrying loads of up to 500 kilograms in order to evaluate its fitness for proposed missions. The physical experiments showed that the performance of the prototype closely matched the Adams predictions. “If we had not used Adams to optimize the design prior to building the prototype, we would probably have needed five additional prototypes at a cost of $100,000 each to get the design right,” Pan said. “With Adams, the first prototype worked exactly as intended so we did not have to make a single change.”

Benefits:
  • The Adams/View command language works well for parametric modeling of robots
  • The performance of the prototype closely matched the Adams predictions
  • Applying Adams simulation early in their robot design saved five additional prototypes at a cost of $100,000 each

 
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Company:

Auburn University

Products:

Adams

Industries:

Biens de consommation

Sample of Auburn University Projects Utilizing MSC Adams

Overview:

Auburn University fielded a senior design team working to compete in the 2016 AFRL University Design Challenge. The senior design team designed and constructed the TRIAD (Tactical Rope Insertion Assist Device) to assist soldiers in a rapid decent. During the design process, Adams was utilized to model the flexible rope and the TRIAD and simulate how the device would perform. The flexible rope was modelled using beam elements with material properties that replicated the behavior of the actual Nylon rope used in practice. An image of one of these simulations is provided in Figure 1. The weight of the person using the device is represented by the addition of the weight highlighted in green. Scripts were developed in the form of command files that would enable an Adams user to enter a variety of parameters for the rope for quick model building and further simulations. These simulations revealed some problems in the preliminary designs that were also seen in testing, and these problems were subsequently addressed for the final design and competition prototype.

Auburn University worked in developing user written subroutines and an Adams plugin that would predict the wear rates of objects rattling inside of an enclosure. An example of this includes a projectile with attached shoe (Figure 2), that can slide out from the enclosure upon release. During transport the projectile could rattle causing wear of the enclosure. An experimental wear study was performed to determine wear coefficients, which were employed in an Adams simulation to determine contact forces, contact area, wear rate and total wear over time.

We have worked with them on undergraduate capstone design projects and graduate student research projects, where we design and build a physical prototype, run experiments and performance studies on those, and virtual prototype in Adams.
David Beale, Professor, ME

 
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Company:

Interseals

Products:

Marc

Industries:

Automobile

Gasket Manufacturer Delivers Product 16 Weeks Earlier by Reducing Prototype Iterations with Marc FEA Simulations

Overview:

The traditional approach for suppliers to the automobile industry has been to build parts according to drawings provided by original equipment manufacturers (OEMs). Today, OEMs are delegating much more of the design responsibility to suppliers. This trend significantly changes the role of suppliers who, instead of competing primarily on quality, price and delivery time, are now often judged based on their ability to develop an innovative design that can meet the OEM’s requirements and be produced at a high level of quality and a low cost.

As a leading supplier of gaskets to the automotive industry and other markets, Interseals responded to these trends by increasing the size and capabilities of its engineering team. Yet, in the past, the company still faced difficulties in meeting its customers’ requests for innovative and economical designs. Gaskets are difficult to design because rubber components can undergo large deformations under load, sustaining strains of up to 500% in engineering applications. The load-extension behavior of rubber is extremely nonlinear and time and temperature dependent. Previously, when Interseals engineers based their initial designs on experience and handbook formulas, they usually found that the initial prototype did not meet the customer’s requirements. Typically, it took two more iterations to get the design right. Each design iteration cost an average of 5,000 Euros in tooling expenses and took between six and eight weeks.

Results Validation:

Interseals engineers shared the simulation results with the customer and the customer gave the go-ahead to build the mold. When the mold was completed, Interseals made a number of prototypes and provided them to the customer. “The customer tested the prototypes and said that they met every requirement,” Izzo said. “Getting the design right the first time saved an estimated 10,000 Euros in additional tooling costs and made it possible to deliver the gaskets 16 weeks earlier than if 2 additional prototype iterations had been required as was normal with our previous design methods.”

Benefits:
  • Marc has been capable of predicting the complex nonlinear behavior, while taking into account time and temperature effects and calculate compressible and incompressible material models based on test data.
  • Using simulation allowed the customer to save an estimated 10,000 Euros in additional tooling costs and made it possible to deliver the gaskets 16 weeks earlier than with the previous design methods

 
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Company:

Tenneco Inc.

Products:

Actran Acoustics

Industries:

Automobile

Exhaust Active Noise Cancellation

Overview:

An automobile’s exhaust system is becoming more and more critical to its success in the marketplace. Most important, the sound produced by the vehicle serves to a considerable degree as the signature of the brand. For example, an auto enthusiast can recognize the approach of a Bentley or Ferrari with his or her eyes closed. Purchasers of lower-priced vehicles may not be quite so finicky but they still expect to hear a certain sound when they start up the engine. Meanwhile, automotive original equipment manufacturers (OEM) are being forced by government regulations to reduce the levels of noise emitted from the tailpipe. Automakers are also hoping to reduce the back pressure of exhaust systems in order to achieve improvements in fuel economy.

It’s becoming increasingly difficult to meet these often conflicting goals using conventional passive exhaust system technology which relies upon the use of perforated tubes and chambers to filter out acoustic waves. Automotive original equipment manufacturers (OEMs) are looking at active exhaust systems as a way to address these issues. Active exhaust systems use a loudspeaker driven by a microprocessor to cancel out unwanted sound generated by the engine as well as to produce more desirable sounds. A key advantage of active exhaust systems is that they can be controlled by software to adjust the output of the loudspeaker to deliver just the right sound under a wide range of different operating conditions.

Results Validation:

“Actran has enabled Tenneco to develop a process for electroacoustic simulation of an active exhaust system including the loudspeaker and housing that correlates very well with physical experiments,” said Nicolas Driot, Senior Core Science Engineer for Tenneco. “We are now using simulation to develop our next generation active exhaust system. Simulation will make it possible to evaluate the performance of many alternative design concepts in a minimal amount of time without the expense of building physical prototypes. This should make it possible to improve the performance of the exhaust system beyond what can be achieved with the traditional process where only a few different design alternatives can normally be evaluated. Simulation will also make it possible to bring new products to market faster.”

Benefits:
  • Actran results match very closely with physical test measurements both when modeling the loudspeaker alone and then when simulating the loudspeaker integrated it in a complete exhaust system.
  • Simulation allows evaluating the performance of many alternative design concepts for active noise cancellation in a minimal amount of time without the expense of building physical prototypes.

 
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