Static Analysis Overview
Description
Use to calculate deformations, stresses, and strains on your model in response to specified loads and subject to specified constraints.
A static analysis can tell you if the material in your model will stand stress and if the part might break (stress analysis), where the part might break (strain analysis), how much the shape of the model changes (deformation analysis), and the effects of loads on any contacts (contact analysis).
Perform a static analysis when the loads and other boundary conditions on your model will not change over time, or the load frequency is less than approximately one-third of the structure's lowest natural frequency.
Typically, static analyses produce interesting results for stress and displacement:
• If the stress in a part exceeds a certain value, the part may fail. Interpreting stress results depends on the type of material and the nature of the loading. For example, most engineering materials are ductile and thus will yield prior to fracture.
Von Mises stress is generally considered most accurate for predicting ductile material failure. Maximum Shear (Tresca) theory may also be used for ductile materials. Since brittle materials fail in fracture, you may want to use the
Modified Mohr theory in such cases. Composite structures generally have different modes of failure, and thus require different theories for predicting them, such as
Tsai Wu,
Maximum Stress, or
Maximum Strain. If the loads are cyclical in nature (that is, they are applied and removed many times, like an automobile running over a rough road surface), the part may fail at a lower stress due to
fatigue.
• The displacement results produced by Creo Simulate indicate how the structure will deform under the applied boundary conditions. Most designs need to be both stiff enough to perform a job and strong enough not to break.
You can produce reliable stress and displacement results from a static analysis by making sure you:
◦ Model the loads and boundary conditions as realistically as possible.
◦ Ensure that the geometry of the Creo Simulate model accurately reflects the geometry of the real part in areas where high stresses may occur.
For example, if you suppress a round in an area where
Creo Simulate finds a high stress, the reported stress will be much higher than in reality (since theory predicts that an inside corner will produce an infinitely high stress or
singularity). Additionally,
Creo Simulate will require more computer time and resources to calculate these unrealistic stresses.
Requirements
• 1 constraint set
• 1 or more load sets or enforced displacements
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To analyze the model without applying any constraints, use the Inertia Relief option on the Static Analysis Definition dialog box.
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