Method for optimizing the mass of a composite panel

• US 8,181,345 B2
• Filed: 07/20/2007
• Issued: 05/22/2012
• Est. Priority Date: 07/20/2007
• Status: Active Grant

• Current Assignee: Airbus Operations SAS (Airbus SE)
• Original Assignee: Airbus Operations SAS (Airbus SE)
• Inventors: Carpentier, Alban, Grihon, Stephane
• Primary Examiner(s): Taousakis, Alexander P
• Application Number:
  US11/780,842
• Publication Number:
  US 20090022945A1
• Time in Patent Office: 1,768 Days
• Field of Search: 294/191, 298/97, 298/972, 298/892, 428/119, 700/28, 700/52, 700/97, 703/1
• US Class Current: 29/889.2
• CPC Class Codes: B32B 2605/18 Aircraft blades, propellers B32B2603/00
• CPC Class Codes: B32B 5/024 Woven fabric
• CPC Class Codes: B32B 5/12 characterised by the relative arrangement of fibres or filaments of different layers, e.g. the fibres or filaments being parallel or perpendicular to each other
• CPC Class Codes: G06F 2111/06 Multi-objective optimisation, e.g. Pareto optimisation using simulated annealing [SA], ant colony algorithms or genetic algorithms [GA]
• CPC Class Codes: G06F 2113/24 Sheet material
• CPC Class Codes: G06F 30/3323 using formal methods, e.g. equivalence checking or property checking
• CPC Class Codes: Y10T 29/4932 Turbomachine making
• CPC Class Codes: Y10T 29/49616 Structural member making
• CPC Class Codes: Y10T 29/49622 Vehicular structural member making
• CPC Class Codes: Y10T 29/49801 Shaping fiber or fibered material
• CPC Class Codes: Y10T 428/24174 including sheet or component perpendicular to plane of web or sheet

Abstract

A method for optimizing the mass of a composite panel composed of a plurality of uniform thickness zones, each zone defined by a vertical arrangement of plies, each arrangement having a different number of piles, and different orientation angles, where a positioning order of the plies has a given orientation angle with respect to the others in the vertical arrangement, and the proportion of plies has a given orientation angle with respect to all the plies composing the vertical arrangement. The optimization includes defining a lay-up table, and defining a vertical arrangement of plies for each uniform thickness zone, and starting from the lay-up table, building a function describing the physical properties of each zone as a function of the total thickness of each zone, where the total thickness for each zone is adjusted using a discrete variables iteration process, until the mass of the panel is a minimum.

Claims

1. A process for making a composite panel, said panel being composed of a plurality of uniform thickness zones, each uniform thickness zone being defined by a vertical arrangement of plies having different orientation angles, said arrangement being defined by a determined number of plies, a positioning order of the plies having a given orientation angle with respect to the others in the vertical arrangement, and the proportion of plies having a given orientation angle with respect to all the plies composing the vertical arrangement, said process comprising:

a first step of defining a lay-up table describing an optimal arrangement of plies taking into account mass constraints as well as structural constraints imposed to the panel;

a second stage comprising producing the panel, including arranging the panel to include different plies with different orientation angles in accordance with the optimal arrangement described in the table lay-up, so as to realize said plurality of zones of uniform thickness;

the first step further comprising the steps of;

defining a lay-up table, said table defining a vertical arrangement of the plies for each uniform thickness zone;

starting from said lay-up table, building a function describing the physical properties of each zone of the composite panel as a function of the total thickness of each zone;

adjusting the total thickness for each zone using a discrete variables iteration process, to minimize the mass of the panel,

said adjustment of the total thickness for each uniform thickness zone resulting in a modification of the number of plies for each of said uniform thickness zones using the corresponding lay-up table.

2. The process according to claim 1, wherein defining the lay-up table includes building the table by determining idealistic proportions of plies having a given orientation angle with respect to the total thickness for each uniform thickness zone of the panel using a discrete variables iteration process, so as to minimize the total mass of the panel.

3. The process according to claim 2, further comprising upon completion of building the table:

defining a function giving the proportion of plies having a given orientation angle as a function of the total thickness for each uniform thickness zone; and

determining the optimum total thickness using a discrete variables iteration process, so as to minimize the total mass of the panel.

4. The process according to claim 3, wherein the derivative of the said function is positive so as to impart ply continuity between two adjacent uniform thickness zones.

5. The process according to claim 1, comprising, prior to building a function describing the physical properties of each zone of the composite panel:

adjusting the positioning order of the plies having a given orientation angle different from the others in the arrangement for each uniform thickness zone using a discrete variables iteration process, the aim of the process being reached when the buckling resistance corresponds to a predefined threshold value.

6. The process according to claim 1, the lay-up table is a pre-existing lay-up table for building the function describing the physical properties of each zone of the composite panel.

7. The process according to claim 1, wherein upon completion of building a function describing the physical properties of each zone of the composite panel, determining the exact number of plies for each uniform thickness zone of the panel using a discrete variables iteration process, the aim of the process being reached when the mass of the panel is minimum.

8. The process according to claim 1, wherein all the plies composing the vertical arrangement have the same thickness.

9. The process according to claim 1, wherein the said composite panel is a plane or curved panel.

10. The process according to claim 1, wherein the plies are unidirectional pre-impregnated plies.

11. The process according to claim 1, wherein the plies are woven plies.