Finite element analysis is just one of many tools in an engineer’s toolkit to help solve problems and find answers. Its applications cover almost every aspect of interest, including force, shock, earthquake, temperature, noise, vibration, friction, durability, stiffness, and weight.
Finite element analysis programs typically import CAD geometry and create a mesh that divides the volume or area into smaller volumes or areas called elements. Imagine that each element is like a spring, and each spring is connected to each other to form a large spring. The benefit of this approach is that any CAD model of any shape or form can be checked for stress and deformation before a prototype is made. In other words, finite element analysis is virtual prototyping.
Finite element analysis provides the ability to quickly and cheaply explore various prototype options and designs. This makes finite element analysis an important tool for improving product performance, reducing costs, and shortening project delivery cycles. If you build and test a prototype, you may find that the prototype suddenly breaks at 50% load. You will then build another prototype, make the failed part thicker, and retest it. You may then find that your prototype fails at 75% load in a different place. The design and test cycle is repeated until 100% load is achieved without any failure or damage.
On the other hand, your prototype may pass testing the first time without using FEA, but you won’t know what your reserve factor is, unless of course you test to destruction. If you decide to test to destruction, you will need several prototype components for each design iteration. For example, if you have three design choices in three similar materials and three load cases, you will need to test at least 27 prototypes to destruction.
You will never really know what your good design is, because the cost and preparation time to build so many prototypes and test equipment is unacceptable.
One of the advantages of FEA is that you can find stresses in any part of the CAD model before you build a prototype, so you can predict which areas are likely to fail first and which second and third areas are likely to fail at higher loads. With the correct application of FEA, you can effectively perform design iterations on simulation models instead of physical prototypes.
Another advantage of FEA is that you can see things that you can’t see along the build and test route. For example, if you overload a gray iron casting, the deformation may not be noticeable until it suddenly cracks or breaks. Now, if you want to make it stiffer in a certain direction, it is difficult to measure such a small deflection on a test rig. With FEA, deflections are easily visible, which helps you understand load paths and reinforce the structure in the most effective way.
Building and testing prototypes for large components and structures is very expensive. Imagine how much it would cost to have a test bench on a 20-meter-long, 50-tonne overhead mobile crane to prove the reliability of seismic motion. On the other hand, FEA has no restrictions on size or weight. (We recommend you to follow the “Mechanical Engineer” public account to get the dry goods knowledge and industry information at the first time)
Another thing to consider for plastic components is that your prototype may be a different material than the component you manufacture. Injection molds for high-volume production are very expensive, so you may only be able to manufacture and test your component with similar materials instead of production materials. Similar plastics can have very different mechanical properties, especially when subjected to high or low temperatures and repeated load cycles. FEA will give you the opportunity to quickly explore different material options with minimal cost.
FEA is particularly useful for safety-focused components in highly regulated industries, such as pressure vessels. There are many design specifications and standards that require accurate calculation of stresses in order to check against allowable stresses. Some parts of the AS ME specification allow the stresses generated by FEA to be used directly to check compliance with the required standards.
Finite Element Analysis is just a tool, and like any other tool, it takes an engineer with enough experience to understand how to use it properly. The most important attribute of any financial analyst is not their ability to drive a software package, but their ability as an engineer.
What FEA Can Do Specifically
Finite Element Analysis is the most commonly used tool for stress and structural analysis. It can also receive input data from other tools such as kinematic analysis systems and computational fluid dynamics systems. FEA software can be used for:
Mechanical engineering design
Computer-aided drafting and engineering simulation services
Structural analysis
Modal analysis
Solid mechanics
Mold flow analysis
Fatigue and fracture mechanics
Thermal and electrical analysis
Sheet metal forming analysis
Most of today’s FEA software is very accurate. What divides FEA services is not the software, but the experience of the team. Some of the factors that affect the test results are accurate inputs of geometry, physics, material properties, and loads. It is also important to remember that since most FEA tests are performed under ideal circumstances, it is the broad interpretation of the results, not the actual numbers, that separates the good from the great FEA companies. This is also why companies that provide FEA services should have experience in different industries.