Linear Elastic FEA in SolidWorks Simulation: Fast and Reliable Mechanical Design Validation

When you're designing structural components—whether for a subsea tool, a lifting frame, or a pressure vessel—it's vital to trust that the design can withstand expected loads. Before you invest time in fabrication or assembly, it's wise to validate the design's performance. That’s where Linear Elastic Finite Element Analysis (FEA) comes in.

Linear elastic FEA is a go-to tool for early-stage validation. It’s efficient, reliable, and reveals how a part responds to static loading without the need for physical prototypes.

Understanding Linear Elastic FEA in SolidWorks Simulation

FEA is a computational method used to approximate the stress, strain, and deformation of a component or assembly under load. The model is divided into finite elements governed by constitutive equations, which are solved to estimate the structural response. This process allows engineers to assess stress concentrations, load paths, and displacement behavior, provided the setup and mesh are robust.

In a linear elastic analysis, two key assumptions are made:

• Linearity: Stress and strain are proportional.

• Elasticity: The material returns to its original shape when the load is removed.

  
  

These assumptions simplify calculations. As long as stresses remain below yield limits and deformations stay small, linear elastic FEA is highly effective for verifying structural integrity.

Applications of Linear Elastic FEA in Mechanical Design Validation

Linear elastic FEA serves many purposes:

• Verifying stress and deflection limits

• Evaluating alternative designs or materials

• Ensuring adherence to ASME, API, DNV, or customer specifications

  
  

It’s particularly valuable for fabricated structures, mounting frames, machined housings, pressure-retaining parts, and mechanical tools. Early stress validation can prevent issues later in the design process.

Speed and Efficiency in SolidWorks Simulation

SolidWorks Simulation is efficient for handling linear static studies, especially for single parts or assemblies with bonded contacts. In these scenarios, the solver can operate in a single pass, avoiding contact nonlinearities and large-displacement iterations. With a well-meshed model, results are available quickly.

However, introducing contact sets or allowing for large displacement adds solver overhead—even in linear studies—since stiffness matrices must be updated iteratively. Although less demanding than nonlinear plastic analysis, these settings increase complexity and solve time.

Efficiency heavily relies on setup. Solver time is only part of the equation. Engineers must use sound judgment to define realistic boundary conditions, select proper material models, and simplify geometries without compromising accuracy.

Mesh quality is equally critical. While automatic meshing is helpful, high-stress areas—such as notches, transitions, or load transfer features—often require manual refinement. A coarse mesh may yield quick results, but without a mesh sensitivity study, stress values may not converge with refinement.

Singularities or high-stress zones at geometric discontinuities must be evaluated carefully. An experienced analyst can determine whether to dismiss, address, or further investigate such results.

Once defined properly, SolidWorks Simulation provides a fast, dependable platform for evaluating mechanical designs and iterating improvements.

Practical Example: Offshore Lifting Frame

Consider a custom fabricated frame used to lift and secure equipment on an offshore vessel. These frames must handle high static and dynamic loads, with design factors accounting for vessel motion and environmental forces.

Using linear elastic FEA in SolidWorks Simulation, stress and deflection can be evaluated under amplified static loads that consider offshore lifting dynamics. With a clean model—bonded contacts, accurate loads, and refined mesh at weldments and padeyes—the results can confirm that no region exceeds allowable stress and that deflections stay within acceptable limits.

This method supports design documentation, internal reviews, and client approvals without necessitating more complex nonlinear or dynamic analyses.

When Is Linear FEA Sufficient?

Linear FEA is suitable when:

• The design operates well below yield limits

• Interactions are straightforward and well understood

• The goal is to verify stress margins or deflection limits

  
  

It’s ideal for many early to mid-phase validations. However, if your design approaches yield, includes nonlinear material behavior, or requires realistic contact scenarios, a nonlinear study may be necessary.

Concluding Thoughts

Linear elastic FEA is among the most valuable tools in mechanical design validation. It allows for fast, code-compliant evaluations of components and structures prior to fabrication.

If you're working on a mechanical system that needs validation—especially for offshore, subsea, or structural applications—reach out. I can assist with the analysis, interpret the results, and ensure your design is backed by solid engineering.

Lateral Engineering Solutions offers FEA-driven validation, optimization, and documentation services for demanding projects. Let me know how I can support your project.

Localized high stresses at sharp corners of welded padeye joint due to discontinuities at modeling simplifications and linear elastic assumptions.

Written by Les E. Griffin, P.E. - Principal Engineer at LES.