The effect of resin properties on the strength of filamentary structures

1989 ◽  
Vol 24 (2) ◽  
pp. 107-113 ◽  
Author(s):  
T J Lu ◽  
X Ji ◽  
X R Gu
Keyword(s):  
Failure Mechanisms ◽  
Critical Factor ◽  
Pressure Vessels ◽  
Resin Matrix ◽  
Experimental Investigations ◽  
Filamentary Structure ◽  
Burst Strength ◽  
Advanced Composite Materials ◽  
Matrix Properties ◽  
Area Of Concern

The adoption of advanced composite materials has significantly improved the performance of solid motor cases, but the failure mechanisms of this kind of filamentary structure are still far from understood, especially with respect to the influence of resin properties. Experimental investigations are reported in the present paper and the results show that the effect of resin matrix properties on burst strength of fibre-wound pressure vessels can be as large as 20—35 per cent. Hence, how to optimize resin matrix properties is a key area of concern in the rocket motor industry. Using improved netting analysis, delamination observed in the head area of the pressure vessels is concluded to be the critical factor leading to burst-strength degradation. Various pressure vessels failure mechanisms are also discussed.

Statics and Dynamics of Elastic Shells with Cutouts —A Review

1974 ◽  
Vol 18 (02) ◽  
pp. 113-126
Author(s):  
J. Pattabiraman ◽  
V. Ramamurti ◽  
D. V. Reddy
Keyword(s):  
Dynamic Loading ◽  
Nuclear Reactors ◽  
High Reliability ◽  
Pressure Vessels ◽  
Experimental Investigations ◽  
Concentrated Loads ◽  
Stress Concentrations ◽  
Elastic Shells ◽  
Statics And Dynamics ◽  
Static And Dynamic Loading

The purpose of this survey is to give a review of the methods and results of analytical and experimental investigations for stress concentrations in thin elastic shells subjected to static and dynamic loading. The increasing use of higher-strength materials in the design of pressure vessels, aircraft, ships, and nuclear reactors with high reliability necessitates more precise analyses in the regions of cutouts and concentrated loads.

A Comprehensive Study on Burst Pressure Performance of Aluminum Liner for Hydrogen Storage Vessels

2021 ◽  
Vol 143 (4) ◽  
Author(s):  
Serkan Kangal ◽  
A. Harun Sayı ◽  
Ozan Ayakdaş ◽  
Osman Kartav ◽  
Levent Aydın ◽  
...  
Keyword(s):  
Internal Pressure ◽  
Axial Strain ◽  
Cylindrical Part ◽  
Pressure Vessels ◽  
Fe Analysis ◽  
Burst Pressure ◽  
Experimental Investigations ◽  
Fe Model ◽  
Stress Criterion ◽  
Analytical Approaches

Abstract This paper presents a comparative study on the burst pressure performance of aluminum (Al) liner for type-III composite overwrapped pressure vessels (COPVs). In the analysis, the vessels were loaded with increasing internal pressure up to the burst pressure level. In the analytical part of the study, the burst pressure of the cylindrical part was predicted based on the modified von Mises, Tresca, and average shear stress criterion (ASSC). In the numerical analysis, a finite element (FE) model was established in order to predict the behavior of the vessel as a function of increasing internal pressure and determine the final burst. The Al pressure vessels made of Al-6061-T6 alloy with a capacity of 5 L were designed. The manufacturing of the metallic vessels was purchased from a metal forming company. The experimental study was conducted by pressurizing the Al vessels until the burst failure occurred. The radial and axial strain behaviors were monitored at various locations on the vessels during loading. The results obtained through analytical, numerical, and experimental work were compared. The average experimental burst pressure of the vessels was found to be 279 bar. The experimental strain data were compared with the results of the FE analysis. The results indicated that the FE analysis and ASSC-based elastoplastic analytical approaches yielded the best predictions which are within 2.2% of the experimental burst failure values. It was also found that the elastic analysis underestimated the burst failure results; however, it was effective for determining the critical regions over the vessel structure. The strain behavior of the vessels obtained through experimental investigations was well correlated with those predicted through FE analysis.

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

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.

Analysis of Burst Conditions of Shielded Pressure Vessels Subjected to Space Debris Impact

2005 ◽  
Vol 127 (2) ◽  
pp. 179-183 ◽  
Author(s):  
Igor Ye. Telitchev
Keyword(s):  
Fracture Mechanics ◽  
Crack Propagation ◽  
Space Debris ◽  
Failure Mechanisms ◽  
Pressure Vessels ◽  
Unstable Crack ◽  
Nonlinear Fracture Mechanics ◽  
Nonlinear Fracture ◽  
Catastrophic Fracture ◽  
Debris Impact

The present paper summarizes the results obtained from impacts on shielded pressure vessels and analyzes the conditions under which bursting of a shielded pressure vessels occur that are damaged by space debris. The semianalytical model was generated to describe the processes occurring upon impact of a hypervelocity projectile into a shielded vessel. A model capable to describe the failure mechanisms of damaged vessels is suggested. Nonlinear fracture mechanics techniques were used to analyze and predict whether a vessel perforation will lead to mere leakage of gas, or whether unstable crack propagation will occur that leads to catastrophic fracture of the vessel. The validity of the developed model is tested by simulating the experimental results.

scholarly journals The Dynamic Behaviour of Pile Foundations in Seismically Liquefiable Soils: Failure Mechanisms, Analysis, Re-Qualification

2020 ◽  
Author(s):  
Rohollah Rostami ◽  
Slobodan B. Mickovski ◽  
Nicholas Hytiris ◽  
Subhamoy Bhattacharya
Keyword(s):  
Dynamic Behaviour ◽  
Failure Mechanisms ◽  
Shaking Table ◽  
Pile Foundations ◽  
Experimental Investigations ◽  
Winkler Foundation ◽  
Buckling Instability ◽  
Seismic Liquefaction ◽  
Liquefiable Soil ◽  
Design Loads

This chapter presents a concise overview of the mechanics of failure, analysis and requalification procedures of pile foundations in liquefiable soils during earthquakes. The aim is to build a strong conceptual and technical interpretation in order to gain insight into the mechanisms governing the failure of structures in liquefaction and specify effective requalification techniques. In this regard, several most common failure mechanisms of piles during seismic liquefaction such as bending (flexural), buckling instability and dynamic failure of the pile are introduced. Furthermore, the dynamic response commentary is provided by critically reviewing experimental investigations carried out using a shaking table and centrifuge modelling procedures. The emphasis is placed on delineating the concept of seismic design loads and important aspects of the dynamic behaviour of piles in liquefiable soils. In this context, using Winkler foundation approach with the proposed p–y curves and finite-element analyses in conjunction with numerical analysis methods, are outlined. Moreover, the feasibility of successful remediation techniques for earthquake resistance is briefly reviewed in light of the pile behaviour and failure. Finally, practical recommendations for achieving enhanced resistance of the seismic response of pile foundation in liquefiable soil are provided.

Several Failure Analysis Cases of Pressure Equipment Under the Conditions of Complex Medium Environment

2011 ◽  
Author(s):  
Xuedong Chen ◽  
Zhibin Ai ◽  
Tiecheng Yang ◽  
Zhichao Fan ◽  
Weihe Guan
Keyword(s):  
Failure Analysis ◽  
Failure Mechanism ◽  
Preventive Measures ◽  
Effective Means ◽  
Failure Mechanisms ◽  
Pressure Vessels ◽  
Influential Factors ◽  
Complex Medium ◽  
Complex Environment ◽  
Failure Prevention

There are several hundred of failure cases of pressure vessels and piping in China every year. The causes for part of accidents have been clearly analyzed, and preventive measures have been taken making the similar accidents substantially reduced, but the causes for quite a few failure accidents are still not found effectively, the similar accidents is still taking place. Through study, the authors find that the major reason for deviation of failure analysis lies in that equipments are mostly operating in complex medium environment, and mutual competition may exist among multiple failure mechanisms. Sometimes changes of some influential factors may cause the dominant failure mechanism change, even leads to totally different analysis conclusions. Combining with the analysis and verification of several failure cases of pressure vessels and piping in petrochemical enterprises, the judgment method for the dominant failure mechanism under multiple failure mechanisms is discussed in this paper, which may be helpful to provide some effective means for failure prevention of pressure equipment under complex environment.

scholarly journals Role of magnetic field evolution on filamentary structure formation in intense laser–foil interactions

2019 ◽  
Vol 7 ◽  
Author(s):  
M. King ◽  
N. M. H. Butler ◽  
R. Wilson ◽  
R. Capdessus ◽  
R. J. Gray ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Rear Surface ◽  
Target Volume ◽  
Formation Time ◽  
Intense Laser ◽  
Experimental Investigations ◽  
Filamentary Structure ◽  
Foil Target ◽  
Field Formation

Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.

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