Learning Forum

[aromalabraham]

What is meant by 1D, 2D, 3D analysis in ansys ? Is it that for 1D, we consider the body as line body and is used when one dimension is significantly larger than the other two, 2D where body is considered as shell were two dimensions are of importance and 3D when the body is considered as a solid where all the three dimensions are of importance ? Or there there more to it ? 

[Erik Kostson]

Hi

In ANSYS for structural simulation (static structural) we only have 2D and 3D type of analysis.

We have only 2D (say plane strain or stress) with X and Y movemenet only (so in the XY Plane), and elements (plane182) have X,Y degrees of freedom (dof)

And 3D analysis with X,Y, Z movemenet in space, and thus elements have X,Y,Z dof (e.g., solid185, or solid186).

You can read more about these elements and analysis in the help manual (just search for these elements there).

All the best

Erik

[mohan.urs]

Hey,

In addition to what Erik said, Do check out the links below.

In Ansys, 1D, 2D, and 3D analysis refer to the dimensionality of the model and the type of elements used in the simulation.

1D analysis typically involves elements that have only one dimension, such as a line or beam, and is used for problems where the geometry can be simplified to a single dimension. This type of analysis might be used for elements that are much longer in one dimension than the others, like cables or trusses.

2D analysis uses elements that have two dimensions, such as shells or plates, and is suitable for problems where the thickness of the object is small compared to the other two dimensions. This allows for the analysis of planar structures or objects with axisymmetric geometries.

3D analysis involves three-dimensional elements and is used for problems where all three dimensions of the object are significant. This type of analysis is the most comprehensive and is used for complex geometries where the stresses and strains need to be evaluated in all three spatial dimensions.

For instance, Ansys Mechanical supports mixed-dimension analysis, where structurally important parts of the design are modeled in 3D, while other aspects can be geometrically modeled in 2D, 2D-axisymmetry, or even 1D. This approach balances the need for accuracy with greater speed and cost-effectiveness.
https://ansyshelp.ansys.com/public//Views/Secured/corp/v242/en/wb_sim/ds_2d_simulations.html
https://innovationspace.ansys.com/courses/courses/structural-boundary-conditions/lessons/understanding-when-to-take-advantage-of-symmetry-lesson-3/

Additionally, when discussing 2D structural analysis, it's important to clarify the terms of dimensionality as different programs may have different meanings for 1D, 2D, or 3D elements. In Ansys, for example, shell elements might be referred to as 2D elements because they operate in a plane and have no thickness, whereas in other contexts, they might be considered 3D due to their spatial orientation.

Lastly, deformation or deflection in Ansys is represented differently in 1D, 2D, and 3D spaces. In 1D, deformation is a scalar quantity, while in 2D and 3D, it is represented as a vector.
https://courses.ansys.com/index.php/courses/mechanical-strain/lessons/lesson-4-strain-tensor-2/

Thanks,

Mohan Urs