In the previous article - Composites Structural Design, we discussed how structural composite design is performed, involving CAD, CAE, and CAM. In this blog, the focus is on structural design tools at different stages of the design process.
Conceptual design
Detailed structural design
Design for Manufacture
Design of tooling
Composite structure designs are challenging due to the wide range of design variables e.g. materials, laminates, and interactions. The use of a design tool in an industrial environment speeds up the process and allows investigation for an optimal solution through several possible concepts. A design goes through multiple stages, as shown in the image below
Design tools
Different tools should be used at different stages of the design process
Laminate design tools
Analytical design tools for structural elements
Finite Element (FE) software for more complex structures
Production design tools
Laminate design
Ply calculation
Determining the Engineering constants e.g. laminate strengths, thermal, and hygrothermal expansion coefficients of each ply are some of the first key steps of the design process. Design tools come with a database containing mechanical data gathered for specific laminates. Alternatively, some design software allows the designer to efficiently compute ply properties for possible configurations using micromechanics theories.
Laminate design
Laminated composites are made up of several plies bonded together. Plies may have a different fiber material, thickness, and/or orientation. The laminate design tool is used for finding feasible and efficient laminates for given design constraints such as weight,
cost and geometric constraints.
Laminate evaluation
A laminate evaluation enables the analysis of composite laminates subjected to in-plane loads, out-of-plane loads, and thermal loading. Mainly used for tailoring a stacking sequence and inspecting the laminate behavior layer by layer.
A non-exhaustive list of laminate design tools is provided in the table below
Analytical design tools for structural elements
Analytical design tools assist the conceptual and preliminary design of layered composite structures, where an exact elastic solution can be found. Analytical tools require the input of the composite structure geometry and the loadings as well as the constitutive laminate properties, imported directly from the laminate tool. Analytical design tools offer the possibility to analyze several layered composite structural elements such as:
Homogeneous and laminated plates
Sandwich plates
Stiffened panels
Beams
Curved plates
Cylindrical shells
Bonded joints
Bolted joints
A non-exhaustive list of products and their capability is provided in the table below
Finite Element (FE) software for more complex structures
Finite Element Analysis (FEA) techniques with optimization codes to radically improve the design of complex parts. FEA tools allow for either the importation of lay-up definitions from laminate design tools or the rapid creation of ply lay-ups. These tools provide different failure criteria for specific applications,
Tsai-Hill
Hoffman
Tsai-Wu (with Cowin extension)
Hashin (fiber and matrix)
A good FEA tool can feed results back to the design tool to enable updates to be made that can be rapidly re-imported into the analysis tool with the minimum of re-applying loads and meshes. The below table shows FEA packages that have composite materials capabilities
Key takeaways
Industry uses a variety of tools for performing the micromechanical to layup scale simulation.
These tools also have their advantages for the given load case
Most of these tools are independent solutions and may not have the interoperability to provide a unified design environment
Looking for AFP simulation software for your business? Schedule a demo with Pravin Luthada or James Kuligoski via LinkedIn now to customize a solution for your needs.
About Addcomposites
Addcomposites is the provider of the Automated Fiber Placement (AFP) ecosystem - including the Fiber Placement System (AFP-XS), 3D Simulation and Programming Software (AddPath), and Robotic Cells (AddCell). With the leasing program for the AFP system (AFPnext), composites manufacturers can work with thermosets, thermoplastics, dry fiber placement, or in combination with 3D Printers on a monthly basis.