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[hanif132]

Hello, i want to ask something about mesh convergent. I had do my analysis about static structural and i use several size of mesh. But i dont know how much percent of error to be say that it is converged. Can someone help me?

[Sahil Sura]

The Percentage error value for the convergence depends on the application and the accuracy accepted by the user. Like in cases for test runs, demonstrations, a low level of accuracy can be accepted but for critical design applications, high level of accuracy involving minimal level of error is needed.
Some generic guidelines for the error are as follows which may sound a good reference for determining the expected error -
At maximum accuracy, when convergence isnotsought, studies of problems with known answers yield the following behaviors and approximated errors:
Less than 20% error for peak stresses and strains, and minimum margins and factors of safety.
Between 5% and 10% error for average (nominal) stresses and elastic strains, and average heat flows.
Between 1% and 5% error for average stress-related displacements and average calculated temperatures.
5% or less error for mode frequencies for a wide range of parts.
You might also want to try the Adaptive convergence feature in Ansys Mechanical to avoid the manual iterations and get the expected results.
You may refer to the following resources for more information-
Convergence (ansys.com)
Using Adaptive Convergence (ansys.com)
Using Adaptive Convergence with Ansys Mechanical ÔÇö Lesson 5 - ANSYS Innovation Courses
Hope that helps!
Thanks Sahil
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