Optimization of composite structures involves ply material, thickness, angle, and stacking sequence. However, a highly optimized composite structure may not be easily manufactured. So, HyperX evaluates each variable not only for weight and positive margins of safety, but also for producibility.
Setup for Composite Sizing follows the established HyperX pattern:
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Set up a Design Property with a Composite Material.
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Set up an Analysis Property with Composite Failure Modes.
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Set up a Load Property (not composite-specific).
Available Concepts
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Unstiffened Panels
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One Stack
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Two Stack
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Three Stack
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Foam Sandwich
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Honeycomb Sandwich
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Stiffened Panels
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Any Stiffened Panel geometry can be Sized with Composite Materials
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I, Z, T, hats, etc.
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Composite Sizing Constraints
Note
Implement constraints on the Design Property – consider manufacturability when setting these constraints.
Ply Angle %
Set limits on the percentage of total thickness allowed for each orientation and min/max bounds on total Ply count.
Layup Rules
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Symmetry - Laminate is mirrored about the midplane (midplane Ply is allowed).
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Balance - Equal number of + and – 45s.
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Place +45 adjacent to -45 - 45 Plies are always paired with the conjugate.
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Apply 45 rule after N plies - If a block of N consecutive adjacent Plies (of the same orientation) occurs in the stack, the Plies adjacent to that block cannot have an angle delta greater than 45 degrees.
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Use +45 fabrics only - If Sizing with fabric material, no -45 orientations will be generated.
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Max adjacent plies - Limits the number of Plies of the same orientation that can be placed together.
Sizing with Effective Laminates OR Rapid Sizing
Inputs - Ply Angle Percentage bounds, Layup Rule preferences, Thickness bounds (EL only).
Outputs - Optimum Zone thickness, Ply Angle Percentages.
In this workflow, rather than generating discretely defined Laminates, the optimization will result in only Thickness and Ply Angle Percentage for each Zone. There are two possible sizing routines that generate this result fidelity:
This workflow is particularly advantageous for early design and trade studies, as both sizing routines have quick runtimes. These results can also be taken one step further by using them as inputs to another composites optimization workflow below. Collier Aerospace particularly recommends Sizing with Laminate Families where these results are used as inputs for Laminate Family Generation.
Sizing with Orphan Laminates
Inputs - Ply Angle Percentage bounds, Layup Rule preferences, Thickness bounds.
Outputs - Discretely defined Laminate for each Zone, with option to Sequence results into global Plies.
This is the workflow that previous HyperSizer users are likely most familiar with. While this process does produce Zones with weight-optimum Laminates, the results are typically difficult to Sequence into global Plies - as Orphan Laminate solutions are less likely to be compatible with their neighbors. This is why the Laminate Family Sizing process is typically recommended. See Sizing with Effective and Discrete Laminates.
Sizing with Laminate Families (Recommended)
Inputs - There are a few different input options for the Laminate Family workflow, as there are several different ways to obtain Laminate Families.
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Program standard Laminate Family (manually created or imported from Excel).
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HyperX can also generate Laminate Families from:
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Laminates imported from FEM
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Plies imported from CAD
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Preliminary Sizing Results from Effective Laminates
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Ply Angle Targets and Layup Rules
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Outputs - Discretely defined Laminate for each Zone, with option to Sequence results into global Plies.
The quickest and most robust Sizing approach recommended by Collier Aerospace engineers is Detailed Sizing with a Laminate Family - where the optimum Sizing result for each Zone is chosen from a predefined selection of Candidate Laminates. Since a Laminate Family consists of Laminates that are related to one another, a weight optimum and manufacturable design is obtained in less steps.