Consumer Products | Blog | SimScale https://www.simscale.com/blog/category/consumer-products/ Engineering simulation in your browser Fri, 01 Dec 2023 15:06:21 +0000 en-US hourly 1 https://wordpress.org/?v=6.4.2 https://www.simscale.com/wp-content/uploads/2022/12/cropped-favicon-32x32.png Consumer Products | Blog | SimScale https://www.simscale.com/blog/category/consumer-products/ 32 32 NEW Features: Custom Wind Comfort Criteria, Thermal Resistance Networks, Surface Tension, and More! https://www.simscale.com/blog/new-features-q2-2023-wind-comfort-criteria/ Tue, 17 Oct 2023 15:42:48 +0000 https://www.simscale.com/?p=83107 As a cloud-native platform, SimScale has been consistently performing constant maintenance and releasing new simulation features...

The post NEW Features: Custom Wind Comfort Criteria, Thermal Resistance Networks, Surface Tension, and More! appeared first on SimScale.

]]>
As a cloud-native platform, SimScale has been consistently performing constant maintenance and releasing new simulation features to empower users to simulate better and innovate faster. In Q2 of 2023, SimScale released highly anticipated features and updates to the product, including custom criteria and plots for wind comfort, surface tension for multiphase flow applications, and cylindrical hinge constraint boundary condition.

Let’s get you up to date with SimScale’s new key features released in Q2 2023.

1. Custom Wind Comfort Criteria/Plots

SimScale already provides today a variety of different Pedestrian Wind Comfort Criteria, like Davenport, Lawson, London LDDC, NEN8100, and more.

Still, this list can never be exhaustive as there are a multitude of locally used and adapted comfort criteria that are either required by local authorities or have proven to be well suited to the specific local conditions.

SimScale enables our users to define their own comfort criteria with custom wind speed ranges and percentage thresholds.

With this new possibility, a range of new comfort criteria can be created. Here are some examples:

  • CSTB Wind Comfort Standard
  • Auckland Wind Comfort Criterion
  • Melbourne Wind Comfort Criterion
  • Bristol Wind Comfort Criterion
  • Israeli Wind Criteria
  • Murakami Wind Comfort Criteria
Screenshot of SimScale UI with custom comfort criteria highlighted.
Figure 1: Custom comfort criteria, Boston, shown alongside the default criteria.

2. Thermal Resistance Networks for IBM

This feature is a natural extension to the Immersed Boundary solver and is already available for Conjugate Heat Transfer. It provides thermal resistance networks like two-resistor or star resistor models in the simulation setup and allows you to define detailed components like chips or LEDs as customized components. This avoids the necessity for very fine meshes for those often tiny components.

Users can define a thermal resistance network (TRN) by assigning the top surface of a cuboid as a TRN.

Model the chip as a simple cube in a CAD model or replace the detailed 3D model via ‘Simplify’ on SimScale.

3. Multiphase: Surface Tension

With the addition of surface tension, users of the new multiphase module will be able to improve the accuracy of multiphase results for surface tension dominant flows like microgravity sloshing, capillary flows, microfluidics, etc.

Animation 1: Drops of water falling into a large body of water with surface tension enabled

4. Ogden Hyperelastic Model

We have added this model to better simulate highly elastic rubber. In the animation below, you can see the movement of two solid parts coming together and separating again. There is a hollow rubber seal between them with significant deformation.

Use Case & Benefits

  • Accurately simulate rubbery and biological materials at high strains
  • Increasing hyperelastic functionality
Animation 2: Crushing and releasing a rubber seal

5. Cylindrical Hinge Constraint

The Cylindrical hinge constraint boundary condition replicates the behavior of a fixed hinge. The assigned surface is constrained such that only rotational motion around the hinge axis is free.

SimScale can automatically detect the axis of the hinge based on an assigned cylindrical surface, but the boundary condition also allows for a user-defined input.

beam with cylindrical hinge constraint boundary condition in SimScale
Figure 2: This beam is deforming around two hinge points (the left and central holes are hinged)

6. CAD Swap Improvements

When replacing one CAD model with another, it isn’t always clear what worked and what didn’t. With this feature, we add clarity so that users know what was successful and what requires their attention.

A swap report window in SimScale showing details of CAD swap
Figure 3: Swap report in SimScale clarifying CAD model swaps that require attention

7. Parametric Studies

Boundary conditions can now be parametrized to run multiple simulations with a button click. Some examples are:

  • Electronics: change inlet flow rates, change the heat load on parts
  • AEC: change inlet flow rates to understand the impact on cooling strategies
  • Rotating Machinery: change the inlet velocity and rotational velocity and compare designs

8. CAD Extrude Operations

Extrude is similar to move, although it will maintain the same cross-sectional area — often very useful.

This video shows one move operation followed by one extrude operation. Notice how the extrude option maintains the shape of the adjacent surfaces.

Animation 3: Contrary to the Move operation, the Extrude operation maintains the shape of the adjacent surfaces.

9. Distance Measurement

This is a highly requested feature, and I think we have answered nearly all use cases with this first iteration. We now offer the ability to measure the length/area of an entity and also measure the distance between two entities.

This is a globe valve and an orange line shows the currently highlighted measurement between two of it’s surfaces.
Figure 4: Measuring the distance between two surfaces

Take These New Features for a Spin Yourself

All of these new features are now live and in production on SimScale. They are really just one browser window away from you!

If you wish to try out these new features for yourself and don’t already have a SimScale account, you can easily sign up here for a trial or request a demo below. Please stay tuned for our next quarterly product update webinar and blog.

Are you getting the most out of cloud-based simulation? Check out our subscription plans and capabilities, choose the right solution for your business, and request a demo today.

The post NEW Features: Custom Wind Comfort Criteria, Thermal Resistance Networks, Surface Tension, and More! appeared first on SimScale.

]]>
Dynamic Response and Dynamic Shock Analysis in FEA With SimScale https://www.simscale.com/blog/dynamic-response-and-shock-analysis-fea/ Thu, 24 Aug 2023 11:16:03 +0000 https://www.simscale.com/?p=78550 Dynamic response analysis and dynamic shock analysis are prominent Finite Element Analysis (FEA) applications in various...

The post Dynamic Response and Dynamic Shock Analysis in FEA With SimScale appeared first on SimScale.

]]>
Dynamic response analysis and dynamic shock analysis are prominent Finite Element Analysis (FEA) applications in various engineering disciplines, including automotive, aerospace, and civil engineering.

Their purpose? To explain how structural systems behave when they are subjected to dynamic loadings.

Imagine you’re standing on the edge of a freeway, watching cars whizz by, or perhaps looking at a towering skyscraper standing firm against a turbulent wind. The forces and movements you observe are dynamic, constantly changing, imposing loads that challenge these structures.

This article delves deep into understanding the dynamic response, dynamic shock analysis, and their nuances. We will explore the implementation of these analyses in SimScale and how a cloud-native platform enables such FEA simulations. This article also sheds light on the intricate processes of these simulations and the subsequent interpretation of results for optimal system design.

What Is Dynamic Response Analysis?

Dynamic response analysis involves analyzing the behavior of structures under dynamic loading conditions (loads that can change in magnitude, direction, or frequency over time).

Picture a structure under dynamic loads: The load magnitude fluctuates, the direction alternates, and even the frequency evolves with time. Static studies tend to perceive these loads as constant, overlooking essential factors like damping and inertial forces.
However, reality often defies these assumptions. Loads are dynamic, varying with time and frequency.

Dynamic response analysis is designed to address this deficiency by providing a methodology to handle non-constant load conditions. It is typically employed when the frequency of a load exceeds one-third of the basic frequency.

Animation 1: EV Inverter dynamic response

To get a sense of the distinction between static analysis and dynamic analysis, consider the equations used in finite element models:

$$ [K] \vec{u} = \vec{F} \tag{1}$$

$$ [M] \ddot{\vec{u}} + [C] \dot{\vec{u}} + [K] \vec{u} = \vec{F} \tag{2}$$

Where \(\vec{F}\) the load vector, \([K]\) is the global stiffness matrix, \([M]\) is the global mass matrix, \([C]\) is the global damping matrix, \(\vec{u}\) is the displacement vector, \(\dot{\vec{u}}\) is the velocity vector, and \(\ddot{\vec{u}}\) is the acceleration vector.

\([M] \ddot{\vec{u}}\) is the inertial force (i.e., mass times acceleration) and \([C] \dot{\vec{u}}\) represents the damping force (i.e., damping coefficient times velocity). These terms represent the dynamic forces that distinguish dynamic simulations from static simulations.

The computation of this analysis is typically conducted via simulation software, which determines the simulation’s characteristic response by integrating each mode’s contribution to the load.

The value of using dynamic response analysis depends on various aspects of loading:

  • How often it changes (load frequency)
  • How big it is (load magnitude)
  • Which way it’s going (load direction)
  • How long it lasts (load duration)
  • Where it’s applied (load location)

Dynamic response analysis can be further subdivided into several types of analysis, namely modal analysis, harmonic response analysis, and transient dynamic analysis.

Modal Analysis

Modal analysis is an analysis type that identifies the inherent dynamic properties of a system in order to create a mathematical model, called the modal model, that describes its dynamic behavior using modal data. It helps define the system’s natural characteristics, such as its natural frequency, damping, and mode shapes (mode shapes represent the characteristic displacement pattern of the system).

By studying the frequency and position of a structure, modal analysis enables us to specify when the system would experience resonance, which is the point at which the applied excitation is equal to the system’s natural frequency. This helps make informed design decisions so that phenomena like resonance are avoided.

Simulation image of a wishbone suspension
Figure 1: Wishbone suspension frequency analysis

Harmonic Analysis

Harmonic analysis is a type of dynamic response analysis that simulates the steady-state behavior of solid structures subjected to periodic loads, providing frequency-dependent results. In other words, it studies the response of linear structures under a load varying sinusoidally with time.

Harmonic analysis is particularly useful for evaluating the effects of vibrating forces or linear displacements over a range of frequencies.

Transient Dynamic Analysis

Transient dynamic analysis is a method used to assess the behavior of deformable bodies under conditions where inertial effects play a significant role. It provides time-dependent results, making it particularly useful for evaluating the effects of rapidly applied loads.

ConditionsRecommended Analysis
Inertial and damping effects can be ignored.Linear or Nonlinear Static Analysis
Purely sinusoidal loading and linear response are considered.Harmonic Response Analysis
Bodies can be assumed to be rigid, and kinematics of the system are of interest.Bodies can be assumed to be rigid, and the kinematics of the system are of interest.
Any other caseTransient Structural Analysis
Table 1: A quick reference guide to determine the most appropriate analysis method based on the specific conditions of the system under examination.

What Is Dynamic Shock Analysis?

Dynamic shock analysis specifically focuses on the response of a structure or system to sudden, high-intensity loads or impulses. It aims to assess the behavior and integrity of the structure under extreme loading conditions, such as impact, collision, or explosive forces.
Imagine an extreme scenario – an automotive crash structure colliding, an aircraft experiencing a hard landing, or an electronic device enduring a drop impact.

This is where dynamic shock analysis takes the stage, specializing in understanding how your design would respond to sudden, high-intensity loads.

While dynamic response analysis is a generalist, shock analysis is a specialist, addressing the extraordinary events where high-intensity, rapid-loading events are involved. By doing so, it helps optimize designs for maximum energy absorption and minimum deformation, predicts potential failures for safety enhancement, and even aids in meeting regulatory requirements.

What Is Dynamic Shock Analysis Used for?

Design Optimization

It helps optimize the design of automotive crash structures, ensuring they can absorb maximum impact energy while minimizing deformation and reducing the risk of occupant injury.

Animation 2: Battery module under 50G shock load

Safety and Failure Prediction

It enables the assessment of structures subjected to sudden loads, such as aircraft components during a hard landing, to predict potential failures and improve safety measures accordingly.

Animation 3: Headphone drop test showing Von Mises stress build-up during impact

Regulatory Compliance

Dynamic shock analysis assists in meeting regulatory requirements, such as testing electronic devices to ensure they can withstand drop impacts within specified limits.

SimScale simulation image showing von Mises stress distribution over a valve-spring assembly
Figure 2: Nonlinear dynamic analysis of a valve-spring assembly showing Von Mises stress over the body.

Research and Development

It aids in developing resilient and durable materials for applications like protective gear, where the analysis evaluates their ability to absorb and dissipate impact energy effectively.

SimScale simulation image of a snap fit dynamic stress analysis
Figure 3: Snap fit dynamic stress analysis

FEA for Dynamic Response and Shock Analysis

Imagine being able to simulate the dynamic and shock conditions your design would endure and predict its response – without physical trials. That’s the power of finite element analysis (FEA).

By creating computerized models of structures and applying suitable loads and boundary conditions, you can foresee how these structures would react to dynamic loads and shocks.

The methodology of FEA involves breaking down the structure’s model into thousands of small, interconnected ‘finite elements.’

SimScale simulation image of dynamic stress analysis of aluminum plate rolling
Figure 4: Dynamic stress analysis of aluminum plate rolling showing Von Mises stress

These elements closely represent the intricate features of the structure, thus enabling accurate calculations of stress, strain, and displacement under dynamic and shock loadings.

To learn more, check out this step-by-step guide to dynamic analysis.

Now, let’s go one step further and introduce SimScale into the equation. This is where your journey toward efficient and accurate solutions begins. SimScale’s Structural Mechanics software is a powerful tool that allows engineers to virtually test and predict the behavior of their designs under dynamic and shock conditions.

Maximize Efficiency with SimScale Simulation

SimScale’s cloud-native platform enables engineers and designers to simulate early in the design process without the hassle of software installation and expensive hardware. It empowers design teams and simulation experts alike to test their designs under various conditions by running multiple simulations simultaneously using the power of the cloud. This minimizes the testing time significantly and enables quicker design optimizations, thus enabling faster innovation. Experience the power of collaboration, innovation, and optimization with SimScale’s cloud simulation, accessible anytime, anywhere. Simply sign up, import your 3D design, and start simulating immediately in your web browser.

Nevertheless, the benefits of SimScale don’t stop at accessibility. It also brings your projects into the collaborative sphere, allowing you to share them with your colleagues and teams. This facilitates rapid design improvement and significantly shortens your workflow.

Take, for instance, TechSAT, a prominent company in the aerospace industry. They use SimScale’s simulation capabilities to optimize and validate the performance of their products. SimScale has significantly reduced TechSAT’s time to develop new products. Here is what other customers have said about SimScale.

If you’re an engineer or a product developer eager to make your design process more efficient and speed up your innovation process, it’s time to take advantage of cloud computing and take the next step towards efficient and accurate engineering solutions with SimScale’s cloud-native platform. Sign up below or request a SimScale demo today.

Set up your own cloud-native simulation via the web in minutes by creating an account on the SimScale platform. No installation, special hardware, or credit card is required.

The post Dynamic Response and Dynamic Shock Analysis in FEA With SimScale appeared first on SimScale.

]]>
Solid Mechanics Simulation and Analysis with SimScale https://www.simscale.com/blog/solid-mechanics-simulation-and-analysis-with-simscale/ Wed, 31 May 2023 07:53:41 +0000 https://www.simscale.com/?p=72247 Solid mechanics simulation has become an integral part of mechanics, especially in industrial design and manufacturing. It...

The post Solid Mechanics Simulation and Analysis with SimScale appeared first on SimScale.

]]>
Solid mechanics simulation has become an integral part of mechanics, especially in industrial design and manufacturing. It evolved with the development of numerical methods and the immense growth in computation power, enabling engineers to study mechanical phenomena by building accurate 3D models and simulating the behavior of solid materials.

But that’s not all. In this article, we will explore how simulation can not only help study mechanical phenomena but also enable better-informed decision-making early in the design process. In other words, we will see how engineers can benefit from one particular aspect of simulation that provides them with more accessibility, collaboration opportunities, and efficiency in both time and money.

What is Solid Mechanics?

Solid mechanics is a branch of physical science that focuses on studying the movement and deformation of solid materials under external loads such as forces, displacements, and accelerations. These loads can cause different effects on the materials, such as inertial forces, changes in temperature, chemical reactions, and electromagnetic forces. This field plays a critical role in various engineering disciplines, including aerospace, automotive, civil, mechanical, and materials engineering.

Solid mechanics focuses on understanding the mechanical properties of solid materials and their response to different types of loading. These materials include metals, alloys, composites, polymers, and others. By studying how materials behave under different conditions and in different environments, engineers can gain insights into designing and optimizing structures, components, and systems to ensure their safety, reliability, and performance.

In solid mechanics, there are two fundamental elements:

  • The object’s internal resistance that acts to balance the external forces, represented by stress
  • The object’s deformation and change in shape as a response to external forces, represented by strain

The relationship between stress and strain is described by Young’s Modulus, which states that strain occurring in a body is proportional to the applied stress as long as the deformation is relatively small – i.e., within the elastic limit of the solid body. This can be visualized in the stress-strain curve shown below.

Solid shape evolution under tension with a representative stress-strain curve
Figure 1. The shape evolution of a test sample as it undergoes the stages in a stress-strain curve

What is Solid Mechanics Used for?

The importance of solid mechanics lies in its practical applications and contributions to engineering and the industry. The key reasons why solid mechanics is not only practical but crucial for engineers can be categorized as follows:

  • Design analysis
  • Failure analysis and prevention
  • Material selection and optimization
  • Structural safety and load-bearing capacity
  • Performance optimization and efficiency

Design Analysis

Solid mechanics provides the foundation for designing and analyzing structures and components. By applying principles of solid mechanics, engineers can assess the structural integrity and performance of systems and ensure they meet design requirements and safety standards.

It enables them to predict and understand factors such as stresses, strains, and deformations, which are vital in designing structures that can withstand expected loading conditions and environmental factors.

Image showing FEA analysis of a robotic gripper
Figure 2. Robotic Gripper Linear FEA Demo project to analyze stress areas in the structure

Failure Analysis and Prevention

Solid mechanics helps engineers investigate and analyze failures in structures or components. By understanding the causes of failure, such as excessive stress, material fatigue, or deformation, engineers can improve design practices, materials selection, and manufacturing processes to prevent failures and enhance the reliability and durability of products.

Image showing stress analysis of a plastic shelf
Figure 3. Shelf loading analysis to assess the maximum stresses a plastic shelf can withstand before failure

Material Selection and Optimization

Solid mechanics plays a significant role in material selection and optimization. Engineers need to evaluate the mechanical properties of different materials and assess their suitability for specific applications.

By considering factors such as strength, stiffness, toughness, and fatigue resistance, solid mechanics helps engineers choose the most appropriate materials to meet performance requirements while considering factors such as weight, cost, and manufacturability.

simulation image of von Mises stress distribution in snaps of an enclosure
Figure 4. Enclosure snaps design study showing the von Mises stress distribution

Structural Safety and Load-bearing Capacity

Solid mechanics allows engineers to assess the safety and load-bearing capacity of structures and objects. Through analysis and simulations, engineers can determine the structural stability, response to external forces, and ability to withstand static and dynamic loads.

This knowledge is essential in ensuring the integrity of critical structures, such as bridges, buildings, and aircraft, where failure could have severe consequences.

Simulation image of a bolted flange with a sweep mesh showing stress distribution under load
Figure 5. Bolted Flange with Sweep Mesh showing stress distribution under load

Performance Optimization and Efficiency

Solid mechanics helps engineers optimize designs to improve performance and efficiency. By analyzing stress distributions, material usage, and structural behavior, engineers can identify areas for improvement, reduce unnecessary material and weight, and optimize designs for enhanced strength, rigidity, or energy efficiency. This optimization process leads to cost savings, improved product performance, and reduced environmental impact.

Modal analysis safety factor check of a motor shaft under torque
Figure 6. Modal analysis safety factor check of a motor shaft under torque

Using Simulation in Solid Mechanics

Understanding how solid materials behave under different conditions is crucial for a wide range of engineering and design applications. By simulating the behavior of solid materials, engineers and designers can optimize their designs and reduce the need for costly physical prototyping.

Using simulation software, engineers and designers can create virtual models of their designs and analyze their performance under various conditions. They can simulate stresses, strains, and deformations in solid materials.

The example below is a structural analysis of a wheel loader arm. This simulation project enabled the design engineer to study the relative movement between the components and assess the stress performance simultaneously. This assessment was done by calculating the Von Mises stress distribution within the arm. Such an approach almost eliminates the need for physical prototyping in the early stages of the design process.

Simulation image of a static structural analysis of a wheel loader arm
Figure 7. Static structural analysis of a wheel-loader arm

Finite Element Modeling in Solid Mechanics

Knowing that most engineering cases of solid mechanics are nonlinear by nature, analyzing them with analytical solutions may not be feasible. That’s where numerical modeling comes into play.

To simulate solid mechanics cases and assess the material behavior, engineers use finite element modeling (FEM), a numerical method upon which a simulation technique called Finite Element Analysis (FEA) is based.

FEA involves dividing a complex solid model into a finite number of smaller, interconnected elements to approximate the behavior of the structure. By applying appropriate boundary conditions and material properties, FEA can simulate the response of the structure to different loads, allowing engineers to assess stress, strain, displacement, and deformation patterns.

To further understand the details of FEA, check out our dedicated guide to Finite Element Analysis (FEA).

The FEA software in SimScale, for instance, helps engineers and designers virtually test and predict the behavior of solid bodies. This enables them to solve complex structural engineering problems under static or dynamic loading conditions.

Stress distribution in a wheel loader arm (left view)
Stress distribution in a wheel loader arm (right view)

Yet, with all this, you might still be wondering what exactly the single aspect of simulation benefiting engineers today is. Well, it goes beyond the mathematical side of simulation and capitalizes on the integration of another technology: the cloud.

Simulating Faster with SimScale

SimScale combines the capabilities of simulation with the benefits of cloud computing to enable engineers to analyze accurately, collaborate better, and innovate faster.

Using SimScale’s cloud simulation, you can access your simulation projects anytime, anywhere. All you need is a web browser. You simply sign up to SimScale, import your 3D design, and start simulating.

Furthermore, not only are your projects accessible to you, but you can also very easily share them with your colleagues and teams to collaborate on them, improve your designs quickly, and shorten your workflow significantly.

For example, the global engineering and manufacturing company Bühler uses SimScale to enable the collaboration between 15% of its mechanical and process engineers spread across 25 departments in ten business units on four continents.

Are you getting the most out of cloud-based simulation? Check out our subscription plans and capabilities, choose the right solution for your business, and request a demo today.

The post Solid Mechanics Simulation and Analysis with SimScale appeared first on SimScale.

]]>
Nonlinear Static Analysis: Snap-Fit Assembly https://www.simscale.com/blog/nonlinear-static-analysis-snap-fit-assembly/ Fri, 04 Mar 2022 15:00:53 +0000 https://www.simscale.com/?p=49528 Cloud-native engineering simulation enables engineers to test the structural performance and structural integrity of their...

The post Nonlinear Static Analysis: Snap-Fit Assembly appeared first on SimScale.

]]>
Cloud-native engineering simulation enables engineers to test the structural performance and structural integrity of their designs earlier and with accuracy. Advanced solvers that account for thermal and structural behavior can be accessed to provide robust assessments of deformation, stresses, and other design critical output quantities. In this article, we analyze the structural performance and integrity of a casing snap-fit assembly using cloud-native nonlinear static analysis. The focus of this analysis was to detect the peak stress regions, and therefore better understand the likelihood of permanent deformations. After analyzing the structural behavior, the design goal was to ensure safe snap operations, while minimizing the material yielding.

Electronics Enclosure with Snap-Fitting Cover

The model in this case study is an electronics enclosure with a snap-fitting cover. For these types of enclosures, it is very beneficial to conduct a structural analysis early in the design process to optimize the snapping operation. To gather quality design insights, the outputs of interest from the simulations were peak stress regions which are likely to cause permanent deformation and breakage and also snapping kinematics of the snapping operation itself. Performing a trend analysis facilitated the selection of an appropriate snap and support design.

electronics enclosure with snap-fit assembly
Electronics enclosure with a snap-fitting cover model used in performing trend analysis to select an appropriate snap and support design.

Cloud-Native Simulation Workflow

The simulation workflow in SimScale, which can be repeated and applied to many different use-cases, starts by uploading a solid body CAD geometry to the platform. By using automatic body meshing, the model is quickly ready for simulation. Though the geometry of this case study was relatively uncomplicated, the physics used within the structural analysis is complex. With SimScale, capturing valuable insights from complex simulations is simpler and easier to share within teams and organizations, even with varying levels of simulation expertise. Below, the workflow for a nonlinear static analysis is represented. As SimScale facilitates a cloud-driven design study, users can leverage parallel computation and solve both a higher number of design iterations and more iterations of increased complexity.

simulation workflow for nonlinear static analysis
Process of casing snap-fit nonlinear static analysis in SimScale

Nonlinear Static Analysis in the Cloud

To understand the snapping kinematics, a quick animation can be created when post-processing the results. With the help of the animation, the movement of the casing can be better understood and the regions where the stress value has built up above the yield stress can be identified. This offers an opportunity to further optimize the design by changing the shape or using another material to minimize stress. 

post process simulation results of nonlinear static analysis
Animation reflecting final design after the changes in the support and the cover material

After acquiring the results of the first simulation, the next step was to run a few more iterations. Based on the first design results, changes and alterations could be made within the geometry to converge upon a better design candidate. The first design change enacted in this study was deleting one of the faces, and creating a filet instead of a sharp edge. As the CAD changes are done in Onshape, a cloud-based tool, there is no need to download the file from Onshape and then upload it to SimScale—all can be transferred with cloud integration between two platforms. The previous simulation template can be applied to the new geometry exactly as done in the previous step, requiring no reassessment of the physical constraints or the topological entities. They are already automatically reassociated with the new CAD model. 

A further variable to experiment with in order to optimize design is testing different materials. This is easily done by selecting a new material from the materials library in the simulation setup and assigning this material to the lid. In a similar manner, many different design strategies can be tried and further improved. Once the first simulation setup is completed, iterating on top of that is straightforward and fast, with the power of the parallel computation. 

Electronics Enclosure Design Insights

After performing the first simulation on the design provided by the CAD engineer, the regions above the yield stress were clearly identified. Another interesting point detected was the fact that the support structure underneath the snap is not carrying any stress. As it does not provide added benefits to the structure, designers further assessed its significance in terms of manufacturing. In the second design, the snap is located without support underneath. The same result as with the first design is derived, proving that some cost could be saved in terms of manufacturing by removing the non-beneficial support element. And, in the last design, the shape of the snap is changed slightly, and also the sharp edge is rounded at the bottom part to have a smoother snapping operation.

different snap and support configuration tested with simscale
Design insights gleaned by testing different snap and support configurations

Even if the above-yield stress observed on the model was reduced, an overall significant impact was not shown. Here, designers might consider material changes, in addition to shape iterations. Apec, Makrolon 8345, and Stanyl TE300 were tested as alternatives for the lid.

Because Makrolon 8345 is very stiff, it created high stresses and was eliminated as a viable option for this design. Stanyl TE300, on the other hand, produced strong results, significantly reducing the yielded areas.

different material selections tested with simscale
Design insights derived from simulating different cover material selections

As designers decide on the best shape and material for a model, prototyping or final validation analysis are a natural next step. In this case study, we included a validation analysis scenario. In the validation step, the CAE engineer might prefer to increase the complexity by checking how much deformation they will end up with by using a nonlinear material model. This can be accomplished by uploading a fully detailed stress-strain curve of the experimental testing of the material. Absolute peak stresses, as well as permanent plastic deformations, can be observed and measures taken to ensure that the single snap-fitting operation will be safe. Additionally, a mesh independence study can be conducted on top of the automatic meshing settings assigned by default to validate mesh independence on the results. 

Nonlinear Static Analysis in the Cloud

Engineering simulation in the cloud gives mechanical and structural engineers more detailed insight compared to physical testing, which is critical during the early stages of design exploration. This case study shows how nonlinear static analysis in early-stage design allowed three different snap-support design candidates to be tested, along with material selection. The accessibility of cloud-native engineering simulation enables designers and engineering teams to leverage parallel computation capabilities and achieve faster design cycles and more robust design insights.

Set up your own cloud-native simulation via the web in minutes by creating an account on the SimScale platform. No installation, special hardware or credit card is required.

The post Nonlinear Static Analysis: Snap-Fit Assembly appeared first on SimScale.

]]>
How to Create a Smarter Snap-Fit Design Using FEA https://www.simscale.com/blog/smarter-snap-fit-design-using-fea/ Wed, 26 Jul 2017 13:51:08 +0000 https://www.simscale.com/?p=10618 Snap-fits are everywhere you look! Remember your indestructible Nokia 1200? It made use of a very well designed snap-mechanism to...

The post How to Create a Smarter Snap-Fit Design Using FEA appeared first on SimScale.

]]>
Snap-fits are everywhere you look! Remember your indestructible Nokia 1200? It made use of a very well designed snap-mechanism to ensure the device safety through repeated falls (it also survived the acid attacks inside a fish, but that’s a completely different story). The much-loved children’s toys Lego? Snap-fit mechanism. Belt buckles. Food cans. Be it camera covers, car production, a simple battery case for a remote, or even a huge rocket; everywhere we look, we are surrounded by this marvel of engineering.

The question on everyone’s mind now is, why does this omnipresent mechanism break so easily on some bodies, and lasts decades in others? How can you, as a designer or an entrepreneur, ensure customer satisfaction by using a better snap-fit design?

The answer lies in engineering simulation, and particularly FEA.

What Engineering Simulation Brings

Product design is a highly complex process, with multiple objectives, requirements, and constraints, all of which need to be satisfied for the final product to be successful. The important factors that the designer needs to keep in mind include aesthetics, functionality, cost-efficiency, durability, and safety. While the aesthetic appeal of a product is not quantifiable, the other design aspects are; and they can be accurately tested.

In the traditional design process, the initial design is derived from best practices and past experience—which limits creativity and leaves little room for radical innovation. Coming up with a truly new, ground-breaking design, without relying on best practices, however, is risky and can lead to poor performance. The only way to ensure the durability of such a product is to perform a high number of design iterations until all the criteria are met. Traditionally, that means a high number of physical prototypes and a time-consuming and expensive physical testing phase.

new product development product design process with virtual prototyping

Of course, physical testing cannot (and should not) be eliminated from the product design process entirely. However, multiple prototype building cycles—which account for the bulk of financial and time costs—can be easily avoided by integrating virtual simulation into the workflow. With computer-aided engineering (CAE), you still have an iterative design process, but the days, weeks or months of physical testing are replaced with hours or sometimes even minutes of a simulation run.

When Should Simulation Be Considered

Employing simulation at the right stage of the product development process is another important decision for the designer.

Graph showing the change in available design options vs cost of design changes in terms of time from product planning to product launch

It is important to keep in mind that the closer to the product launch, the more costly design alterations become, due to the increasing number of dependencies in the design. At some point, implementing minor changes and improvements is simply no longer cost-effective. With simulation, on the other hand, these design changes can be implemented even before the first prototype is built, allowing iteration on the design from the very beginning of the development process. This can potentially result in lower costs, minimized failure risks, lighter design, improved performance and user experience, and increased product lifetime.

So Why Isn’t CAE an Industry Standard Yet?

Despite all the advantages mentioned above, several barriers have prevented more engineers and designers from integrating simulation into their design process. Here’s how SimScale is aiming to change this:

  • Accessibility (upfront investment). Traditional software needs to be installed locally and needs a significant amount of computing power. That means highly expensive hardware, that stands idle while the simulations are running. With SimScale, all computations are done in the cloud and require no local installation—just a standard web browser.
  • Operating costs. High licensing costs for standard commercial tools put them out of reach for many designers. SimScale starts with a free Community plan with an option to upgrade to an affordable Professional subscription.
  • Know-how. Current CAE tools are not too user-friendly and are designed for CAE experts. This expertise gap can be minimized with intuitive UI, large public project templates library, live support chat, and free training material. Any of the public projects can be imported into the workspace, and once can simply exchange the CAD model, reassign the boundary conditions, and run the simulation without having to know too much about simulation upfront. 
virtual prototyping product design process

Example Study: Smarter Snap-Fit Design Using FEA

The snap-fit design depends on the expected use and life, and can hence vary substantially. Cantilever snap designs are known to be the most common, and the “U” or “L” shape snaps are very popular as well. The design factors to be kept in mind include the shape of the snap, the thickness of the beam, and the ratio of the thickness to the beam length. Optimizing the design of a snap body is a challenging process, and a lot of information regarding the stresses on the body can be obtained from simulations. One can use the information obtained to determine the life cycle of the snap, how much load it can sustain, and under what conditions. This knowledge can be used to determine the expected lifecycle of the part, the different stress concentration regions, and even be used to determine the manufacturing process itself.

Traditionally, engineers have relied on experimentation and physical testing to ensure the reliability of their snap-fits. Yet in addition to being expensive and time-consuming; identifying all stress points through experimentation is highly challenging and the designer risks missing critical information. Simulation simplifies the data analysis necessary to make informed design decisions while saving time and money, and as a result delivering a more reliable product to the market much faster.

In this webinar, we discuss how to make a better snap-fit design. How to ensure that the least possible material is used, and the longest life-cycle achieved, as well as what goes on behind the scenes for ensuring a snap-fit will last forever or break right after the warranty runs out.

Find out how an extraordinary engineering marvel can still be improved with cloud-based simulation, and how it can help you become a better designer!

Project Overview

The project used in this webinar session is publicly available in the simulation project library—feel free to copy and modify it: Finite Element Analysis of a Snap-Fit.

snap-fit design with cross section and taper radiusSnap-fits come in a wide variety of shapes, sizes, and materials. There is no one-design-suits-all—how well the snap-fit design will perform in real life depends heavily on the intended application. Therefore, in order to approach the problem of optimizing its design, the following design parameters need to be determined:

  • Material
  • Cross section shape
    • Constant
    • Varying
  • Cross section type
    • Cantilever snap joints
    • U-shaped snap joints
    • Torsion snap joint
    • Annular snap joints
  • Taper radius

Once all the information is obtained, the simulation setup can proceed. The results can be used to validate the solver for snap-fit design simulations by comparing them to the experimental data presented in the Bayer Material Science paper [1].

After setting up the CAD model, meshing can commence. The mesh defines the accuracy of the result. It should only be fine at the areas of interest: initially, it can be coarse all over, but subsequently, refinements to the areas of interest need to be provided based on the results.

snap fit design mesh with displacement boundary condition and fixed boundary condition

The snap shall be given a displacement boundary condition. The small box against which the body deforms shall be given a fixed boundary condition. Using symmetry conditions allows the decrease of the number of nodes, the increase of the convergence speed, and the reduction of the model size.

Simulation Results

Areas undergoing the highest stress are clearly visible in the simulation results—the snap deforms and snaps into place. This CAD model is already fairly well-designed, with the snap end being tapered, and hence the strain on the final body is not excessive.

snap fit design stress analysis fea simulation
FEA Simulation Results

Without this taper, however, the strain on the snap would be much higher, causing an earlier breakdown and hence limiting the lifetime of the snap.

For comparison, the initial (points) and the final (solid) positions of the snap body can be seen in the image to the right.

snap fit design mating force and deflection force

If these results are compared to the ones presented in the paper, it can be seen that the mating force and the maximum deflection of the snap seen in the simulation closely match the experimental values. The minor difference in results can be attributed to the meshing grade and can be fine-tuned later.

Conclusion

Looking at the results of this simulation, it becomes evident that a proper snap-fit design is essential for ensuring low-stress concentration at points of contact, taper points, and at the deflecting face. A snap-fit has significantly more stress near the deflecting face (head) than on the tail of the deflecting snap. Most importantly, it was discovered that, compared to the snap-fit design with a constant cross-section, a tapered snap has lower stress values (can undergo more cycles) and a longer life (increased durability), and uses less material (cost saving).

In this case, we investigated leveraging FEA to design smarter snap-fit mechanisms—but this is just one example of how designers and engineers can apply simulation tools in the product development process. The SimScale Public Projects library has a wide selection of templates simulating various product use conditions across multiple industries, including automotiveaerospacemachineryelectronics, and HVAC.

Explore it by creating a free Community account.


Discover all the simulation features provided by SimScale. Download the document below.

References

  • Snap-Fit Joints for Plastics, Bayer Material Science: https://fab.cba.mit.edu/classes/S62.12/people/vernelle.noel/Plastic_Snap_fit_design.pdf

The post How to Create a Smarter Snap-Fit Design Using FEA appeared first on SimScale.

]]>