Asymmetric Vented Hat Stringer for Aircraft Structural Rigidity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft hat stringers with ventilation paths compromise their rigidity due to holes, affecting structural support and weight distribution.
Innovation Solution
A vented hat stringer design with a ventilation opening that does not coincide with the symmetry plane of the connection wall, formed from multiple plies of composite material, enhancing stiffness and rigidity without increasing weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If ventilation holes are provided in hat stringers to accommodate ventilation system connections, then ventilation functionality is achieved, but the rigidity and structural strength of the hat stringers deteriorate
Solution Approach 1:
The patent applies asymmetry by positioning the ventilation opening off-center relative to the hat stringer's symmetry plane. Specifically, the ventilation opening is located such that its centerline does not coincide with the symmetry plane of the connection wall, creating an asymmetric mass distribution that generates torque resistance while maintaining ventilation functionality. This asymmetric placement allows the opening to be positioned to optimize both ventilation access and structural rigidity.
2Strength
If hat stringers are made with thicker materials to improve structural support, then strength and rigidity are improved, but the overall weight of the aircraft increases
Solution Approach 1:
The patent applies local quality by concentrating mass specifically in the connection wall region rather than uniformly thickening the entire hat stringer. The asymmetric positioning of the ventilation opening creates localized mass distribution that enhances torque resistance and structural support precisely where needed for aircraft skin reinforcement, while avoiding unnecessary weight addition in other regions of the stringer.
3Ease of manufacture
If ventilation openings are positioned symmetrically on the hat stringer, then manufacturing and alignment are simplified, but torque resistance and rotational stability are reduced
Solution Approach 1:
The patent deliberately employs asymmetry in the ventilation opening placement to achieve torque resistance. The ventilation opening centerline is positioned at a specific offset from the connection wall symmetry plane, creating an asymmetric mass distribution that generates rotational stability and torque resistance. This asymmetric design prioritizes structural performance over manufacturing simplicity, as the offset position can be precisely controlled during fabrication.
Data Source
AI summary
A vented hat stringer for an aircraft comprises a first hat-stringer leg with a first-hat-stringer-leg surface, a second hat-stringer leg with a second-hat-stringer-leg surface, a first hat-stringer sidewall, a second hat-stringer sidewall, and a hat-stringer connecting wall, comprising a hat-stringer-connecting-wall surface and a virtual hat-stringer-connecting-wall symmetry plane, passing through hat-stringer connecting wall. The vented hat stringer further comprises a ventilation opening, extending through at least one of the first hat-stringer sidewall or the hat-stringer connecting wall, or extending through at least one of the second hat-stringer sidewall or the hat-stringer connecting wall. The ventilation opening defines a ventilation-opening centerline, wherein the ventilation-opening centerline does not coincide with the virtual hat-stringer-connecting-wall symmetry plane.