Flexible Vessel with Meridional Tendons and Bulging Barrier

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current flexible pressure vessels face challenges in maintaining structural integrity due to inefficiencies in load sharing between fibers, particularly in broad fabrics, leading to strength limitations and difficulties in designing flexible end caps for high-load applications, especially in space exploration where high strength-to-weight ratios and deployment efficiency are crucial.

Innovation Solution

A flexible vessel design featuring a substantially impervious barrier membrane structure confined by a meridional array of tendons, allowing the barrier to bulge outwards and relieving global circumferential stress, resulting in a natural spheroidal shape that distributes stress statically and independently of vessel size, with optional rigid or flexible end structures for enhanced versatility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If broad fabric structures are used to construct flexible pressure vessels, then the vessel can achieve larger internal volume, but the load sharing between individual fibers becomes difficult to guarantee, leading to reduced structural reliability

Engineering Contradiction:

Improveinternal volumeVSAvoidload sharing between fibers

Core Design Contradiction:

Volume of moving objectVSReliability

Solution Approach 1:

The fabric is segmented into discrete high-strength fiber bundles arranged in a grid pattern, with each bundle acting as an independent load-bearing element. This segmentation ensures that load is distributed across multiple discrete paths rather than relying on continuous fabric load sharing, thereby maintaining reliability while achieving large volume.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses composite construction combining high-modulus fiber bundles (such as Kevlar or Spectra) with a flexible membrane material. The fiber bundles provide structured load-bearing capacity while the membrane provides continuity and volume enclosure, creating a composite structure that achieves both large volume and reliable load distribution.

Inventive Principle:

Principle #40Composite materials

2Strength

If high modulus fibers are used in woven fabric construction, then tensile strength is improved, but it becomes difficult to guarantee proper load sharing between individual fibers, making interfaces and seams potential failure points

Engineering Contradiction:

Improvetensile strengthVSAvoidload sharing between fibers

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

Instead of relying on load distribution across a continuous woven fabric, the invention segments the structure into discrete high-strength fiber bundles arranged in a grid. Each bundle maintains its independence, ensuring that the high tensile strength of individual high-modulus fibers is preserved without creating load sharing problems that would compromise reliability at interfaces and seams.

Inventive Principle:

Principle #1Segmentation

3Weight of moving object

If flexible barrier membrane structure is used confined by meridional tendons, then the vessel achieves collapsibility and high strength-to-weight ratio, but the barrier must be oversized to allow outward bulging between tendons

Engineering Contradiction:

Improvestrength-to-weight ratioVSAvoidbarrier material quantity

Core Design Contradiction:

Weight of moving objectVSQuantity of substance

Solution Approach 1:

The invention employs a flexible barrier membrane that can be oversized relative to the confined space between meridional tendons. This oversized membrane is allowed to bulge outward between the tendons under pressure, creating a flexible shell structure that encloses volume while using minimal material. The membrane's flexibility enables it to assume the necessary curved shape without requiring excessive material quantity.

Inventive Principle:

Principle #30Flexible shells and thin films

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 design achieves a robust, lightweight, and cost-effective vessel with improved strength-to-weight ratio and deployment efficiency, capable of withstanding high pressures and collapsing for efficient packaging, while maintaining structural integrity and flexibility for space applications.

Implementation Method 1

the barrier fabric bulges outwards between restraint tendons. Since membrane stress is proportional to the radius of the distended membrane, rather than carrying the global membrane stress of the vessel, the barrier is subjected only to the local pressure induced stress

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Data Source

PatentUS8186625B2Flexible vessel

Publication Date: 2012.05.29 THIN RED LINE AEROSPACE

AI summary

A flexible vessel includes a restraint structure and a barrier structure. The restraint structure further includes a first portion, and a second substantially rounded end cap portion that is attached to the first portion. The restraint structure also includes an array of tendons. The barrier structure is positioned within the restraint structure. When the barrier contains a fluid, a portion of the load is carried by the restraint structure and another portion of the load is carried by the barrier structure. The flexible vessel is collapsible to occupy a first volume and distended to occupy a second volume. The flexible vessel is part of a system when used in various applications with respect to a craft.