Tech Tip: Linear Static Analyses with Bearing Loads

In mechanical systems, parts often transfer forces through bearings. Because bearings are typically cylindrical, bearing loads often refer to forces that act on cylindrical surfaces that push against each other. This Tech Tip explores the concept of bearing loads and their importance in analyzing mechanical systems with bearings.

Performing Linear Static Analysis

Onshape offers bearing loads as part of the linear static analysis.

Linear static analysis predicts the behavior of structures under static loading conditions. This method assumes a linear relationship between applied forces and resulting displacements, implying that the structure's stiffness remains constant throughout the analysis. This simplification allows for efficient analysis of structures experiencing small deformations in their elastic limit.

Onshape simplifies linear static analysis for users in several ways:

• Users do not have to worry about meshing and mesh density.
• Users do not have to worry about specifying separate connections for simulation. They use the mates defined when an assembly is created.
• Users can access centralized material libraries shared across teams.

Linear Static Analysis of Connecting Rods

Linear static analysis is often the starting point for more sophisticated analyses. With linear static calculations, engineers can achieve the following:

• Stress Analysis - This is the most common use case for linear static analysis. It helps determine the stress concentration factors in the connecting rod, identifying potential areas of failure and optimizing the design to reduce failure from accumulated stress.
• Design Optimization - This involves optimizing the shape and dimensions of the connecting rod to minimize weight while maintaining structural integrity. This can lead to improved engine performance and fuel efficiency.

Applying Bearing Loads for Realistic Load Representation

Bearing loads represent the actual force distribution acting on the connecting rod due to the interaction between the pins and the bearings. Incorporating the distribution of the load provides a more realistic representation of the loading conditions experienced by the connecting rod, which allows for a more accurate representation of stress in the connecting rod.

Ensure the following when using the bearing loads feature:

1. Select Bearing when specifying the load type.
2. Select the cylindrical face where the bearing load is to be applied.
3. Create a mate connector at the center of the bearing and ensure that the direction of the load is correct.

This Tech Tip showed you how to perform linear static analyses with bearing loads. To see this workflow in action, watch the following video: