How to build a strong Hardware product by using FEA.

What if I tell you that you could predict the behavior of your product under different working conditions even before you have a physical prototype in hand? Seems far-fetched right? But yes, this can be achieved with the help of the FEA (Finite Element Analysis).

You might ask,

• What is FEA and how does it work?
• What are its applications?
• How accurate is it?

Let me answer you one by one

What is FEA?

Finite element analysis (FEA) is the means of simulating the behavior of a product under given conditions. In FEA a mathematical model is used to determine the effects of real-world conditions acting on a product. These simulations are done via software that allows the engineers to identify the problems that might occur later. The FEA simulation focuses on the areas of maximum stress, the factor of safety of the product, possible failure points, and many others.

How does FEA work?

Modeling

The first step in the FEA is to create a CAD model of the part on which the analysis is carried out. The model is then simplified by removing features such as fillets, chamfers, threads, etc. The simplification helps in saving the total computational time and unwanted complexity. As someone once said “ The simpler, the better.”

Material definition

Now let’s think of FEA as a painting process. The first step was sketching and it’s done. Now it’s time to color it, in FEA, it’s done by assigning different materials to different parts. If the material that you would want to use in your simulation exists in the material library of your FEA tool, then your job is almost done. But let’s say you are a material science lover and you wish to use some composite like carbon fiber. Now if that material isn’t available in the FEA software library, you can create your own material and define the basic properties such as Poisson’s ratio, density, young’s modulus, etc.

Defining the load

Understanding how to apply the loads is essential in order to simulate an event. Loads are the forces that will occur during the use of the product. To accurately understand potential failure modes, loads should be set as the largest expected value that the product could see during its lifetime, rather than the average loads. To get accurate results, you need to ensure that the loads you apply are acting on the most appropriate surfaces or sections of a surface.

Boundary conditions

In FEA boundary conditions translate as constraining the motions of the geometry also known as restricting the degrees of freedom. The constraints applied to the model in the FEA software should mimic its real-life scenario. Also, the point or the surface of the application must be studied carefully.

To make it clear, let me give an example. Imagine FEA on a seesaw to determine its maximum load-carrying capacity. As we all know, in a sea-saw the pivot remains fixed and the loads are applied at either end. So, in FEA, the fixed constraint is applied to the pivot and the long narrow board is given transitional freedom along a single axis.

Two important things to keep in mind while applying constraints are :

1. Not to over or under-constrain the model.
2. Using constraints at the right places.

Meshing

Okay! Though we have given the FEA software all the input it needs to carry out the analysis, the FEA simulation needs meshing. The mesh is a way of transcribing a 3D object into an array of mathematical points that can be analyzed. The software does provide users the option to regulate the density of the mesh depending on the complexity of the problem.

So, why do we need the mesh in the first place? it is for this reason that the mesh generates millions of small elements that make up the overall shape of the part on which the calculation is run on every single point and then combined to formulate the final result.

Solution

Now the FEA software after carefully examining all our inputs and constraints will successfully generate the results we asked for. The solver also known as the post-processor produces the results graphically with help of color contours. This comes with an excessive visualization to ensure that even the smallest details can be seen. The option of the scaling factor helps the user to extrapolate the results, and the software also provides a simulation that predicts its behavior under the given circumstance. However, it’s totally up to the user how you want to interpret this data.

Factor of safety

In engineering, a factor of safety, also known as a safety factor, expresses how much stronger a system is to take extra loads and stress. At Fasal, we make sure that we have enough headroom in our design that a factor of safety of 5x is achieved.

FEA at Fasal

We at Fasal use FEA as part of our new product development (NPD). We make sure the products that we design are ready for the market by using tools and principles like FEA, DFMEA, DFM, DFA, etc.

FEA on Fasal Kranti to measure pole stability

Application

Since we have a basic understanding of how Finite element analysis works let’s talk about its application and benefits. The important function of FEA is to make sure that product, parts, and assembly components are capable of performing and functioning correctly as expected for the duration of their life. The FEA is widely used for structural design and analysis in the automotive, aerospace, marine, petrochemical industries, and sporting goods along with other wide variety of industries.

1. Rapid Iteration: FEA helps the designer to rapidly iterate and see how design variations effects with the help of the mathematical model when designs are modified or refined the user can swiftly and easily get the results through simulation and predict its behavior and performance in reality. For example, what will happen when you change the material, boundary conditions, loading values, thickness of the mesh, etc.
2. Save money and time: With the help of FEA we can eliminate the need for initial prototypes, this, in turn, reduces the number of prototypes required before progressing to production. It may also help in reducing the cost associated with performing multiple rounds of physical testing.
3. Reducing the risk: it is very important to be precise while setting up the FEA parameters and inputs. This helps in gaining trust in the simulation results. That means we can also gain confidence that the design, process, and material for your product will perform as designed.

Hope this blog about FEA was helpful! Happy Simulating!