HyperWorks Composites Go Multiscale with Expanded Classical Capability

Markku Palantera

Forecasts for composite materials continue to show a very healthy growth throughout the coming decades. While established sectors, such as aerospace and defense, will consume more, composites – in all their forms – continue to penetrate other industries where their characteristics can displace traditional materials; especially where lightweighting becomes a design driver, such as automotive structures and new energy systems. Elsewhere, construction, infrastructure and energy sectors, such as pipe, tank and pressure vessels, need performance coupled with chemical resistance, whereas composite electrical performance is attractive to the electronics and electrical industries.

With the latest advances in materials modeling of heterogeneous materials, Altair Multiscale Designer is all set for industrial applications.

Irrespective of industry sector, for those new to composites, the ability to access and apply verified engineering approaches and methods is crucial to keeping any design-development cycle on track. To meet the needs of both new and experienced engineers working with any complex, multiphase material, the releases of Altair Multiscale Designer 3.4 and Altair ESAComp 4.7 mark a significant advance in the composite capabilities of the Altair HyperWorks platform. Multiscale Designer 3.4 has many new features, along with increased robustness making this release all set for industrial applications. Having been available through the Altair Partner Alliance for several years, the new ESAComp 4.7 release is now readily available to all HyperWorks users under the standard HyperWorks Unit based licensing.

Multiscale Designer provides the latest advances in materials modeling of heterogenous materials.  Accurate modeling on the level of the constituents, such as fiber and matrix in the case of reinforced plastics, can be combined with efficient simulation of the complete structure. ESAComp, on the other hand, relies on classical approaches for the simulation of layered composite structures. The two approaches are complementary: The fundamentals of the structural behavior of composite structures remain unchanged with multiscale modelling bringing better understanding of the behavior at material level. Both Multiscale Designer and ESAComp integrate to the full composites solution provided by Altair HyperWorks, including pre- and post-processing, FE solvers, and optimization.

Multiscale Designer Brings Materials Modeling to New Levels of Engineering

In recent years multiscale modeling of composite materials has become a viable solution to reduce the amount of physical testing needed for accurate material characterization, and to better assess the nonlinear material behavior and failure mechanisms in structural analyses, thus making it possible to get the designs “right first time”.

Altair Multiscale Designer improves composite rupture prediction (Cikoni)

Whether you are working with high-performance continuous fiber-reinforced composites, chopped or particulate reinforced polymers or even reinforced concrete, Altair Multiscale Designer is an accurate, efficient tool for development of multiscale material models and simulation of parts manufactured from any heterogeneous material. Multiscale material modeling aids design, and offers ultimate failure assessment, statistical-based material allowables, creep, fatigue, fracture, and impact simulations. It provides user material plugins to commercial finite element solvers, Altair OptiStruct, Altair Radioss, LS-Dyna, and Abaqus, for the simulation of any part using multiscale material models.

By using 3D FEA Unit Cells with a Reduced Order Model technique, Multiscale Designer provides an unmatched combination of computational efficiency and predictive accuracy over direct homogenization (accurate but computationally inefficient) or other classical homogenization methods (computationally efficient but inaccurate) used by other multiscale modeling frameworks.

By implementing advanced damage and plasticity laws to account for the fundamental physical behavior of various phase materials, Multiscale Designer nonlinear capabilities cover damage models for brittle materials (carbon and glass fibers); plasticity models for ductile materials; advanced hybrid damage and plasticity models for materials that exhibit both brittle and ductile behavior (most polymers). Characterization of the material parameters for Multiscale Designer have well-defined experimental test matrices and procedures with minimal experimental tests required. In addition, Multiscale Designer material models for various product forms have been validated against several experimental data sets for predictive accuracy.

ESAComp a Powerful Toolbox for Classical Composite Analyses

When it comes to structures made of layered composites, Altair ESAComp is used from preliminary and detailed design phases to advanced analyses for the final design verification. ESAComp is “a stress toolbox” providing engineers with all the various classical composite analysis capabilities needed besides the general finite element tools. ESAComp is a stand-alone software tool, but thanks to its ability to interface with widely-used finite element software packages ESAComp fits seamlessly into design processes. On the market for over 20 years, ESAComp has an established userbase in all industries using high-performance composites.

Stiffened panel design for aircraft structures with Altair ESAComp

Starting with the ESAComp Data Bank, it is a valuable resource containing data for a wide selection of composite materials and commercial material systems: fiber, matrix, core, adhesive, plies. Data is collated from many recognized sources and fully referenced. In addition, user and company-specific material libraries can be created and stored in the database, along with data related to design studies. Besides materials, ESAComp objects: fibers/matrix combinations, plies, laminates, beams, panels, cylinders, bonded and mechanical joints, loads, and boundary conditions can be created and added to the ESAComp database.

Altair ESAComp materials database and stress tool box features: laminate design, detailed FE post-processing, joint design (Biofore Concept Car)

A vast range of analysis tools are available for various aspects of composite structural design. From Classical Lamination Theory (CLT) based laminate analyses to analysis of numerous structural elements, along with bonded and mechanical joints. ESAComp is an efficient platform for performing design studies of composite structures undergoing static, environmental loads and combinations thereof. With almost limitless options for selecting and combining the results and its display – failure predictions, buckling and post-buckling, hygrothermal expansion – performing trade-off studies between materials and structural alternatives aids design decisions during design-development.

HyperWorks Integration

To support pre-processing, materials and lay-ups can be transferred from ESAComp to HyperMesh while taking advantage of ESAComp’s capabilities, such as multiple strength sets, environment-dependent material data (e.g. temperature or moisture), the practical user interface for lay-up definition, and its laminate design capabilities. Material and laminate data can be exported in the following solver formats: OptiStruct, Nastran, Abaqus, ANSYS, and LS-DYNA.

To enhance HyperWorks post-processing, FE results together with material and lay-up data of related elements can be transferred to ESAComp for failure analysis. This allows the application of advanced failure criteria such as Puck or LaRC03, which are often not available in solvers. Reserve factors are computed for all layers as well as on laminate level, covering, for example, wrinkling failure and interlaminar shear. This information can be passed to HyperMesh Desktop for visualization along with information on failure modes and critical layers.

Further, ESAComp offers through-the-thickness plots, which illustrate the stresses, strains or reserve factors (margins of safety and inverse reserve factors, respectively). Loads and laminates can be derived from the imported load case to benefit from ESAComp’s whole set of tools for design improvement. Currently supported solver profiles are OptiStruct and Nastran.

While the existing interfaces for other HyperWorks products already provide interoperability, the full integration of ESAComp capability in the HyperWorks composites pre- and post-processing environment is continuing to assure an even better user experience.

Interested in learning more? Check out our upcoming composites webinar series and register to attend our free webinars! 

Markku Palantera

About Markku Palantera

Markku Palanterä is the Director of Global Composites Business Development at Altair, in which role he promotes Altair’s complete offering for composite design, optimization, and simulation. Markku joined Altair in 2017 through the acquisition of Componeering Inc. and its ESAComp software. He was a founder member of the team that started ESAComp software development at Helsinki University of Technology in the early 1990’s as a project for the European Space Agency (ESA). In 2000, Markku along with a few colleagues established Componeering to continue software development and to commercialize ESAComp. He holds a Master’s Degree in Aeronautical Engineering from Helsinki University of Technology.