Composite Materials Module Updates

For users of the Composite Materials Module, COMSOL Multiphysics® version 6.0 brings a new multiphysics coupling, simplified fold-line constraint, and new safety criteria for layered shells. Learn about these and more updates below.

New Coupling Between Layered Shell and Shell

The new Layered Shell-Shell Connection multiphysics coupling makes it possible to mix the Shell and Layered Shell interfaces by defining different stack members within a single layup using either of the interfaces. This modeling approach is sometimes called the multiple model method. This method is often the best choice in terms of accuracy and performance for modeling composite structures where some layers are thick and other layers are thin. You can see this new coupling in the Analysis of a Composite Blade Using a Multiple Model Method tutorial model.

Simplified Fold-Line Constraints in Layered Shell

A new type of formulation for modeling fold-lines, called a Simplified fold-line constraint, has been added to the Layered Shell interface. This new formulation is computationally more efficient than the standard Full fold-line constraint but is less accurate for thick shells. The new constraint type is particularly advantageous for large geometrically linear problems because it has a special linear formulation for this case. The type of fold-line constraint is selected in the Fold-Line Settings section in the settings for the Layered Shell interface.

Stack Member Selection in Layered Linear Elastic Material

In the Layered Linear Elastic Material in the Shell interface, it is now possible to select a single stack member from a Layered Material Stack. This makes it possible to use more than one Shell interface for different layers on the same boundary. The primary application for this functionality is when mixing different shell formulations on the same boundary in the multiple model method. View this new feature in the Analysis of a Composite Blade Using a Multiple Model Method tutorial model.

The COMSOL Multiphysics UI showing the Model Builder with the Layered Linear Elastic Material node highlighted, the corresponding Settings window, and a composite material with multiple layers model in the Graphics window.
The new Stack member option in the Layered Linear Elastic Material node of the Shell interface allows the selection of a limited set of layers as shown in the Graphics window.

New Safety Criteria in Layered Shell

In the Layered Shell interface, several new safety criteria have been added or extended:

  • The Norris and Azzi–Tsai–Hill criteria are new.
  • The Tsai–Wu and Tsai–Hill criteria have been extended with a 2D formulation.

New Operators for Layered Materials

For evaluation at specified locations in the thickness direction, two new physics-scoped operators have been added to the Layered Shell interface and the layered materials in the Shell and Membrane interfaces, .atxd0 (for evaluation in points) and .atxd1 (for evaluation on edges).

These operators take two arguments: the through-thickness location and the expression to be evaluated — for example, lshell.atxd1(2*th,mean(lshell.mises)). This makes it easier to evaluate any quantity in the extra dimension, especially in cases where multiple layered materials are involved in the modeling of composite structures.

New Tutorial Model

COMSOL Multiphysics® version 6.0 brings one new tutorial model to the Composite Materials Module.

Analysis of a Composite Blade Using a Multiple Model Method

An array of three composite blade models comparing the von Mises stress results of the ESL theory (left), Layerwise theory (middle), and multiple model method (right).
The von Mises stresses distribution in a composite blade solved using multiple model method. Results are compared with the Layerwise theory and the ESL theory.

Application Library Title:
composite_blade_multiple_model_method
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