Finite element analysis has made lives of mechanical engineers and design engineers a lot easier. Through simulation techniques, evaluating product designs have become faster, allowing manufacturers to reach their product development goals on time and place their products in the market effectively.
However, FEA simulations are directly dependent on computational power; with an increase in number of elements and nodes, the time required to arrive on a valid solutions keeps on increasing. For complex and large assemblies, the situation becomes even more complex.
However, there are several ways you can perform finite element simulations faster, without affecting the result quality.
A finite element model differs from a model developed for CAD purposes. It is important to simplify the geometry before applying mesh to the model. Design features such as fillets, chamfers and holes can be neglected when not important; as they consume additional elements and nodes, consuming more time to solve the geometry.
Also, models developed through CAD often include small multiple connected surfaces, which can be combined together. This will simplify small features in the model and load abstraction for mechanical analysis.
Optimize Number of Elements and Nodes
It is not true that refining the mesh for the entire geometry will improve the results. Certain regions in the geometry can also be applied coarse mesh without affecting results. As such, it is important to identify regions that require fine mesh quality and the ones that can be modeled using coarse mesh. Regions near holes and contact with each other usually require fine mesh, while coarse mesh can be applied when moving away from those regions.
Use Beam and Shell Elements
Certain geometries can also be modeled using beam and shell elements. Structures with long span and less thickness such as beams, channel sections and sheet metal panels can be applied shell and beam elements which are geometrically 2D but spatially 3D. For truss or long slender beams, beam elements can be applied when meshing.
Using these elements can significantly reduce the number of elements and nodes count and can reduce the simulation time effectively. As shown in the figure, the test model is evaluated using all the three element types: solid, beam and shell separately. It is seen that all the three models yield same results, but simulation time reduces with beam and shell elements.
Bhaumik Dave is a Sr. FEA consultant at Hi-Tech FEA, an India based FEA service provider. He has applied his FEA expertise across several highly complex and big scale projects, consequently managing to seamlessly deliver as per the client requirements.