Aircraft Acoustic Panel Repair Using Dimpled Patch Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing repair methods for acoustic panels in aircraft nacelle structures often diminish the acoustic properties due to misalignment of perforations between replacement patches and the existing top skin, leading to undesirable voids or delamination.
Innovation Solution
A method involving coupling a fiberglass ply to the acoustic panel, creating dimples within the panel's perforations, and aligning these dimples with perforations on a replacement patch, which is then bonded, ensuring the perforation pattern matches the original skin.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If existing repair techniques use overlapping patches without aligned perforations, then the repair process is simple, but the acoustic properties are diminished
Solution Approach 1:
The patent applies preliminary action by creating dimples in the fiberglass ply before bonding the patch. These dimples are formed by pressing the fiberglass against the perforated top skin, so that when the patch is installed, the dimples align with the perforations. This pre-positioning ensures acoustic property retention without requiring complex post-alignment procedures.
2Ease of operation
If perforations are formed on the patch but not aligned with existing top skin, then the patch can be easily installed, but the acoustic properties are diminished in the overlap area
Solution Approach 1:
The patent introduces an intermediary element - the fiberglass ply with dimples - that mediates between the patch and the existing top skin. The dimples act as a template that transfers the perforation pattern from the existing skin to the patch area, ensuring alignment without requiring direct perforation alignment during installation.
3Strength
If the top skin delaminates from the core material, then structural integrity is compromised, but simple replacement methods create voids
Solution Approach 1:
The patent uses a flexible fiberglass ply that can be conformably bonded to the curved surface of the acoustic panel. This thin film approach allows the patch to follow the panel's geometry closely, eliminating voids and ensuring complete bonding between the patch and core material, thereby preventing future delamination.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach maintains the acoustic properties of the panel by ensuring precise alignment and bonding of the replacement patch, effectively repairing damaged areas without compromising the panel's noise attenuation capabilities.
Implementation Method 1
creating dimples in the fiberglass ply using a differential pressure, wherein the dimples are located within first perforations in the acoustic panel
Implementation Method 2
the acoustic panel and the fiberglass ply may be placed in a bag, and a vacuum may be created within the bag
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An acoustic panel (200) for an aircraft nacelle (100) may comprise a perforated first skin (220), a second skin (230), and a core (210) sandwiched between them. A damaged portion of the perforated first skin may be removed. A fiberglass ply (510) may be coupled to the acoustic panel. A pressure differential may cause the fiberglass ply to form dimples (515) within the perforations (325) of the first skin. The fiberglass ply may be used as a template to drill holes in a replacement patch (400).