Composite Cylinders for Deep Sea Applications: An Overview

In order to develop the knowledge base necessary to design deep sea pressure vessels, it is essential to understand the full chain from design and manufacturing through nondestructive testing (NDT) and characterization to long-term behavior under hydrostatic pressure. This paper describes results from European and national research programs focusing on the use of composites for underwater applications over the last 20 years. Initial tests on small glass/epoxy cylinders were followed by large demonstration projects on carbon/epoxy cylinders with implosion pressures of up to 600 bar, corresponding to 6000 m depth. Numerical modeling has enabled end closures design to be optimized for test performance. Thin and thick wall cylinders have been tested under quasi-static, and long-term loading. Both thermosetting and thermoplastic matrix composites have been tested to failure, and the influence of defects and impact damage on implosion pressure has been studied. These deep sea exploitation and exploration studies were performed for oceanographic, military, and offshore applications, and extensive data are available. The aim of this paper is to indicate existing results, particularly from European projects, in order to avoid costly repetition.

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Matrix Microstructural Analysis

10.31399/asm.tb.omfrc.t53030211 ◽

2010 ◽

pp. 211-222

Keyword(s):

High Temperature ◽

Natural Fiber ◽

Fiber Composite ◽

Microstructural Analysis ◽

Fiber Reinforced Composites ◽

Matrix Composites ◽

Thermoplastic Matrix ◽

Carbon Fiber Reinforced Composites ◽

Natural Fiber Composite

Abstract Microstructural analysis of the composite matrix is necessary to understand the performance of the part and its long-term durability. This chapter focuses on the microstructural analysis of engineering thermoplastic-matrix composites and the influence of cooling rate and nucleation on the formation of spherulites in high-temperature thermoplastic-matrix carbon-fiber-reinforced composites. It also describes the microstructural analysis of a bio-based thermosetting-matrix natural fiber composite system.

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Assessment of contact-induced damage mechanisms in thick-walled composite cylinders

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684420923043 ◽

2020 ◽

Vol 39 (17-18) ◽

pp. 679-699

Author(s):

Ruben AJ Weerts ◽

Olivier Cousigné ◽

Klaas Kunze ◽

Marc GD Geers ◽

Joris JC Remmers

Keyword(s):

Damage Tolerance ◽

Numerical Study ◽

Failure Mechanisms ◽

Pressure Vessels ◽

Thick Wall ◽

Thin Wall ◽

Fiber Failure ◽

Damage Mechanisms ◽

Filament Wound ◽

Composite Cylinders

In order to unravel the damage mechanisms occurring in composite-overwrapped pressure vessels (COPVs) subjected to crash conditions, a combined experimental-numerical study has been performed. For the purpose of generality and simplicity, quasi-static contacts on filament-wound cylinders are considered in this paper, as a precursor for geometrically complex impacts on COPVs. Rings with different wall thicknesses are tested to assess how failure mechanisms change when transitioning from thin-wall to thick-wall cylinders. The experimental results are used to identify, which mechanisms occur, and the numerical model is subsequently exploited to analyze the corresponding mechanisms. Based on the understanding of the mechanisms, a method to improve the damage tolerance of thick cylinders is presented. The rings are locally pre-delaminated during manufacturing to promote the growth of these pre-delaminations instead of the initiation of fiber failure.

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Impact damage characterisation of thermoplastic matrix composites using transmission transient thermography

Nondestructive Testing And Evaluation ◽

10.1080/10589759310001642206 ◽

2003 ◽

Vol 19 (3) ◽

pp. 79-90 ◽

Cited By ~ 8

Author(s):

Carlo Santulli*

Keyword(s):

Impact Damage ◽

Matrix Composites ◽

Thermoplastic Matrix ◽

Transient Thermography

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Probabilistic simulation of long term behavior in polymer matrix composites

10.2514/6.1994-1445 ◽

1994 ◽

Cited By ~ 4

Author(s):

A. Shah ◽

S. Singhal ◽

P. Murthy ◽

C. Chamis

Keyword(s):

Polymer Matrix ◽

Polymer Matrix Composites ◽

Matrix Composites ◽

Probabilistic Simulation ◽

Long Term Behavior

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EFFECTS OF LONG-TERM DEEP-SEA IMMERSION ON THE IMPLOSION AND EXPLOSION OF HOLLOW COMPOSITE CYLINDERS

10.23860/thesis-chu-tyler-2021 ◽

2021 ◽

Author(s):

◽

Tyler Chu

Keyword(s):

Deep Sea ◽

Composite Cylinders

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Is inflation targeting useful for economic growth?

Voprosy Ekonomiki ◽

10.32609/0042-8736-2017-2-62-74 ◽

2017 ◽

pp. 62-74 ◽

Cited By ~ 7

Author(s):

P. Kartaev

Keyword(s):

Economic Growth ◽

Monetary Policy ◽

Test Performance ◽

Inflation Targeting ◽

Developing Economies ◽

Empirical Studies ◽

Growth Regime ◽

Potential Channels

The paper presents an overview of studies of the effects of inflation targeting on long-term economic growth. We analyze the potential channels of influence, as well as modern empirical studies that test performance of these channels. We compare the effects of different variants of inflation targeting (strict and mixed). Based on the analysis recommendations on the choice of optimal (in terms of stimulating long-term growth) regime of monetary policy in developed and developing economies are formulated.

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Diode Laser Assisted Filament Winding of Thermoplastic Matrix Composites

Materials ◽

10.3390/ma3010563 ◽

2010 ◽

Vol 3 (1) ◽

pp. 563-571 ◽

Cited By ~ 1

Author(s):

Fabrizio Quadrini ◽

Erica Anna Squeo ◽

Claudia Prosperi

Keyword(s):

Diode Laser ◽

Filament Winding ◽

Matrix Composites ◽

Thermoplastic Matrix

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Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽

10.3390/biology10060522 ◽

2021 ◽

Vol 10 (6) ◽

pp. 522

Author(s):

Régis Santos ◽

Wendell Medeiros-Leal ◽

Osman Crespo ◽

Ana Novoa-Pabon ◽

Mário Pinho

Keyword(s):

Population Structure ◽

Life History ◽

Deep Sea ◽

Management Strategies ◽

Size Composition ◽

Large Size ◽

The Common ◽

Fishing Impacts ◽

Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

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