Composite Pressure Vessels Research Articles

Structural hierarchical optimisation of composite pressure vessel lining design based on FEA-RSM-PSO approach

Structural hierarchical optimisation of composite pressure vessel lining design based on FEA-RSM-PSO approach

Evaluation of the Corrosion Resistance of 904L Composite Plate in a High-Temperature and High-Pressure Gas Field Environment

In order to study the corrosion resistance of 904L composite plate pressure vessels under a high-temperature and high-pressure gas field environment, the pitting corrosion and stress corrosion cracking resistance of a 904L composite plate body and weld material were compared with those of a 2205 composite plate and 825 composite plate, which are used in high-temperature and high-pressure gas field environments. The results showed that the pitting resistance of the 904L composite plate was lower than that of the 825 composite plate and higher than that of a 2205 solid-solution pure material plate and a 2205 composite plate. The corrosion resistance of the 625 welding material is higher than that of the E385 welding material. In the simulation of the corrosion environment of a high-temperature and high-pressure gas field, the corrosion rates of the 904L composite plate body, welding seam, and surfacing welding were all less than 0.025 mm/a, indicating slight corrosion, and the sensitivity coefficient of chloride stress corrosion cracking was less than 25%, indicating low sensitivity. The 904L composite plate met the requirements of corrosion resistance for pressure vessel materials in a high-temperature and high-pressure gas field environment.

Optimizing performance of hybrid fiber reinforced overwrapped pressure vessel

Composite overwrapped pressure vessels (COPVs) offer significant weight advantages over traditional all-metal vessels particularly in industries like aerospace, automotive and pharmaceutical, but pose unique challenges in mechanical design, fabrication, and testing. Despite their benefits, COPVs are susceptible to stress rupture failure, which can lead to catastrophic consequences during operation. This failure mode is not fully understood, with burst pressure-induced extreme stress concentrations and dynamic loading primarily contributing to rapid deformation and strain. To address these concerns, a comprehensive investigation was conducted, focusing on optimizing and examining the effects of optimum winding angle and lay-up pattern configuration on burst pressure in vessels under internal pressure. Finite element modeling analyzed the burst pressure behavior of COPVs with a 4 mm thick aluminum core cylinder and varying layers of carbon/fiber epoxy, each with a constant thickness. ABAQUS composite modeler generated 18 COPV models with carbon fiber/epoxy plies, ensuring uniform thicknesses while exploring different fiber orientations. The effects of ply stacking sequence were analyzed through finite element analysis for all models, comprising varying layers with uniform thicknesses. Attention was paid to failure criteria, methodically evaluating the burst strength of the Al/CFRPC COPVs This exhaustive analysis yielded an optimal COPV design profile characterized by a precisely calibrated ply stacking sequence of [24.50, −24.50] PP winding pattern and six (6) arranged layers. The stress-strain distribution analysis of the Composite Overwrapped Pressure Vessel (COPV) revealed both a uniform distribution of stress across its surface and extreme stress concentration, particularly peaking towards the polar boss region. This concentration is discernible due to variations in ply thickness induced by the overwrapped fiber orientation. This investigation provides valuable insights for optimizing COPV design and enhancing its performance and reliability in various applications.

Theoretical and experimental research on the critical buckling pressure of the thin-walled metal liner installed in the composite overwrapped pressure vessel

Composite overwrapped pressure vessels (COPVs) are widely used in the field of high-pressure gas storage and transportation because of their light weight and high strength. In engineering, autofrettage is usually used to improve the fatigue life of composite pressure overwrapped vessels with metal liners. However, excessive pressure of autofrettage could cause buckling damage to the metal liner. In order to determine the upper limit of autofrettage (critical buckling pressure) and analyze its influence on the safety factor of COPVs, a theoretical calculation model of the critical buckling pressure about the metal liner was established based on classical laminated plate theory and the confined buckling theory. Then, a COPV with thin-walled welded metal liner was prepared by fiber winding process. In order to monitor and judge the buckling damage mode of the liner, the circumferential strain of the COPV's cylinder was measured by loading and unloading step-by-step. Finally, the influence of materials and dimensions of the metal liner on the pressure ratio (the ratio of the first layer failure pressure to the critical buckling pressure of the COPV's metal liner) was discussed. When the diameter to thickness ratio (R/t) of the metal liner was greater than 35, the pressure ratios of the 6063-T5 aluminum alloy liner and the S30408 stainless steel liner both exceeded 2.25. However, the pressure ratio of 6061-T6 aluminum alloy liner with R/t ≤ 60 was lower than 1.85, which shows that the metal liner with higher yield strength and lower elastic modulus has higher utilization rate of fiber winding layers. Due to the fact that the current design standards only ensure the reliability of COPVs through safety factors and various type testing with their evaluation methods, the proposed theoretical calculation method can reduce the uncertainty of COPVs during the design and testing rounds.

Prediction of composite pressure vessels’ burst strength through machine learning

In Hydrogen Fuel Cell Electric Vehicles, hydrogen is stored as compressed gas in tanks made from carbon fiber composite. Tanks are designed to withstand 2.25 times the nominal working pressure. If low variability in tank strength can be demonstrated, this margin of safety could be reduced. This requires accurate prediction of the strength of the vessel and quantification of its uncertainty. In this work, several composite pressure vessels are manufactured using filament winding, and the parameters that control the winding and curing recorded as time signals. Process parameters include fiber tension, winding speed, liner pressure, fiber volume fraction, winding time and curing pressure. The vessels are tested for burst pressure. Several configurations are defined, where each manufacturing parameter is changed. The recorded manufacturing data are fed to machine learning(ML) algorithms and trained to predict the vessel’s burst pressure. These ML algorithms include neural networks, Gaussian process regression GPR, Kernel Principal Component Analysis-Lasso (kPCA-Lasso), and an Ensemble regressor. The KPCA-Lasso and GPR models show good correlation. The Ensemble regressor yields better results by combining the KPCA-Lasso and GPR models. The study demonstrates the potential of ML algorithms in predicting the burst pressure of carbon fiber vessels from the monitored manufacturing data.

Failure monitoring and classification from acoustic emission tests on impact-damaged hydrogen composite pressure vessels

Composite overwrapped pressure vessels (COPV) for hydrogen will play an important role in emission free mobility and energy storage. The DELFIN project (2018 – 2022) was set up with the goal of developing improved COPVs that are lighter, cheaper and more durable. A key aspect of this project was to conduct full-scale impact tests with different gas pressure levels that were used to evaluate the vessels’ crash performance and to verify numerical impact simulations. These tests were followed by controlled pressure experiments until the burst pressure was reached. The procedure was monitored with acoustic emission testing (AT) and subsequent computer tomography (CT). The residual COPV stability and the AT results are compared to different scenarios regarding the impact energies and impact angles. The event localization from AT shows a clear correlation of the emitted energy with the damaged areas. We classify the recorded signals into groups that can be related to the failure mechanism and compare those to the pressure evolution before failure of the COPV. All tests indicate that large impact energies lead to a significant reduction of the burst pressure of COPVs, whereas a higher internal pressure can have a stabilizing effect that reduces the damaging effect.

Assurance of Iintegrity of Composite Pressure Vessels by AE Testing Using Remaining Life Indicator

Composite overpressure vessels (COPVs) are utilized in fuel cell vehicles (FCVs). The remaining life of COPVs decreases with repeated fillings. To indicate this decrease in remaining life, a remaining life indicator is embedded in the vessels. When the remaining life decreases, the indicator fractures before the structural components do. This allows for early detection, signalling the critical life of the vessel. Specifically, the indicator is designed to fracture before the carbon fiber, ensuring the vessel's strength. This fracture is then detected by AE (Acoustic Emission) testing, enabling us to determine the vessel's remaining life. In this study, we embedded the indicator in coupon specimens and conducted a preliminary study to assess the feasibility of our proposed method. As the indicator, we used a carbon fiber with a slightly smaller fracture stress compared to the carbon fiber comprising the vessels. Three types of coupon specimens with different amounts of indicator were prepared, and tensile tests were conducted. As a result, the fracture stress was not affected by the incorporation of the indicator, and the indicator's failure did not induce the fracture of the original CFRP (Carbon Fiber Reinforced Plastic). These results indicate that the integrity of COPVs can be ensured by incorporating the indicator and monitoring the fracture of these materials using AE testing.

Feasibility study of carbon-fiber reinforced polymer linerless pressure vessel tank

Composite pressure vessels are used in aerospace engineering for storing fluids such as propellants, nitrogen, and oxygen. They are also used in life-support systems, High-performance pressure suits for astronauts, Helium Tanks for Balloons and Airships. Among many types of composites, Carbon fiber composites uses have been increasing due to its high strength to weight ratio, high thermal expansion, corrosion, fatigue and impact resistance and design flexibility. In order to improve the volume of the pressure vessel, the liner-less concept is tried. This increased volume efficiency is crucial in aerospace applications where space is at a premium and maximizing storage capacity within limited dimensions is important. Not only the volume efficiency, but also the Reduced Permeability Concerns, Enhanced Durability and Longevity, better thermal continuity and simplified manufacturing process make this research significant in the area of pressure vessel. This research paper deals with the fabrication and development of a cylinder without a lining. The test sample was subjected to several tests: tensile test, impact, shear test (3P Bending), leak test and Pressure test. The test sample was capable of withstanding 20 Bars without failure. The numerical results were also performed and compared with the experimental results. The difference was only 3%. Unsymmetrical dimethyl hydrazine (UDMH) AND red-fuming nitric acid can both be stored in this cylinder (RFNA). Unlike traditional composite overwrapped pressure vessels, the liner-less composite tanks rely completely on the composite shell to act as a permeation barrier as well as handling all pressure and environmental loads. The absence of a liner eliminates the potential for delamination or failure at the interface between the liner and the composite material.

Deep learning-driven predictive tools for damage prediction and optimization in composite hydrogen storage tanks

This research presents a comprehensive framework for predicting the damage in lightweight composite high-pressure hydrogen storage tanks and optimizes their design to prevent failure. By integrating advanced analytical methods, numerical analysis, and deep learning techniques, we introduced a novel approach to enhance design optimization and damage prediction. The framework employs the 3D elasticity anisotropy theory to predict mechanical performance, incorporating failure criteria for accurate damage analysis. A parametric study was conducted to examine the effects of thickness, pressure, and diameter on the behavior of the tank. The analytical results were compared against finite element analysis using the WoundSim software, underscoring the significance of the modeling assumptions. Furthermore, we developed a new framework that combines deep neural networks with differential evolution optimization (DNN-DEO) to predict stress and damage in composite pressure vessels while identifying the optimal design parameters (pressure, radius, and thickness) to minimize failure risks and maintain high performance. A graphical user interface (GUI) was also designed to automate calculations and predictions, providing an intuitive tool for users. This integrated approach offers a powerful solution for optimizing the design and operation of lightweight composite hydrogen storage tanks, ensuring the reliability and efficiency of hydrogen storage systems.

Impact of stacking sequence on burst pressure in glass/epoxy Type IV composite overwrapped pressure vessels for CNG storage

The shift from metallic to composite pressure vessels for storing compressed natural gas (CNG) is driven by the goal of reducing environmental impact by using lighter higher-performing structures. This work focuses on enhancing the internal pressure strength of a type IV composite overwrapped pressure vessel (COPV) by optimising the stacking sequence of the overwrapping composite layers. Parametric finite element (FE) models are developed to reveal symmetry effects. In these models, both the thickness build-up and fibre angle variation at the turnaround zones are accurately modelled. Subsequently, the stacking sequence is optimised with the objective function of maximising burst strength. The parametric modelling demonstrates that representing the COPV as an axisymmetric continuum reduces computational costs in 5400× while yielding results comparable to full 3D continuum models. Experimental burst tests are carried out to validate the numerical predictions, and the difference in pressure between them is 12.6 %.

Design and material optimization of carbon fiber composite winding reinforcement layer for vehicle Type-IV hydrogen storage vessels

Due to the safety, reliability, and high hydrogen storage density of vehicle Type-IV composite overwrapped pressure vessels (COPVs), the Type-IV COPVs are currently the preferred choice for vehicle hydrogen storage vessels. The reinforcement layer bears 80 % to 90 % of the internal pressure load, and it accounts for a significant proportion of the total cost and weight of Type-IV COPVs. Thus, the reinforcement layer is the key problem in the design and optimization of the vehicle Type-IV COPVs. Firstly, this paper proposed a design method for vehicle Type-IV COPVs considering the strength and stiffness of reinforcement layer, and created the hydrogen storage vessel scheme. Then, the stress and strain of vehicle Type-IV COPVs under working and blasting internal pressure were analyzed by finite element simulation. Finally, the genetic algorithm was used to find the best carbon fiber for vehicle Type-IV COPVs. The results show that the scheme designed by the method in this paper can meet the requirements of vehicle use; The carbon fiber modulus most suitable for car hydrogen storage bottle winding is 288.8 GPa, and the weight of the reinforcement layer is reduced by 32 % compared to the T700S carbon fiber composite wound vessel.

Advancement in the Modeling and Design of Composite Pressure Vessels for Hydrogen Storage: A Comprehensive Review

The industrial and technological sectors are pushing the boundaries to develop a new class of high-pressure vessels for hydrogen storage that aim to improve durability and and endure harsh operating conditions. This review serves as a strategic foundation for the integration of hydrogen tanks into transport applications while also proposing innovative approaches to designing high-performance composite tanks. The goal is to offer optimized, safe, and cost-effective solutions for the next generation of high-pressure vessels, contributing significantly to energy security through technological advancements. Additionally, the review deepens our understanding of the relationship between microscopic failure mechanisms and the initial failure of reinforced composites. The investigation will focus on the behavior and damaging processes of composite overwrapped pressure vessels (COPVs). Moreover, the review summarizes relevant simulation models in conjunction with experimental work to predict the burst pressure and to continuously monitor the degree of structural weakening and fatigue lifetime of COPVs. Simultaneously, understanding the adverse effects of in-service applications is vital for maintaining structural health during the operational life cycle.

Mechanical Properties of Clay-Reinforced Polyamide 6 Nanocomposite Liner Materials of Type IV Hydrogen Storage Vessels.

This study focuses on polyamide 6/organo-modified montmorillonite (PA6/OMMT) nanocomposites as potential liner materials, given the growing interest in enhancing the performance of type IV composite overwrapped hydrogen storage pressure vessels. The mechanical properties of PA6/OMMT composites with varying filler concentrations were investigated across a temperature range relevant to hydrogen storage conditions (-40 °C to +85 °C). Liner collapse, a critical issue caused by rapid gas discharge, was analyzed using an Ishikawa diagram to identify external and internal factors. Mechanical testing revealed that higher OMMT content generally increased stiffness, especially at elevated temperatures. The Young's modulus and first yield strength exhibited non-linear temperature dependencies, with 1 wt. per cent OMMT content enhancing yield strength at all tested temperatures. Dynamic mechanical analysis (DMA) indicated that OMMT improves the storage modulus, suggesting effective filler dispersion, but it also reduces the toughness and heat resistance, as evidenced by lower glass transition temperatures. This study underscores the importance of optimizing OMMT content to balance mechanical performance and thermal stability for the practical application of PA6/OMMT nanocomposites in hydrogen storage pressure vessels.

Design and Optimization of a Double-Layer Composite Pressure Vessel Structure

Design and Optimization of a Double-Layer Composite Pressure Vessel Structure

Review of Implosion Design Considerations for Underwater Composite Pressure Vessels

The implosion of underwater composite structures is a critical and complex engineering problem, necessitating high-strength, lightweight, and corrosion-resistant materials for deep-sea applications. This manuscript reviews the intricate failure mechanisms of composite structures, focusing on cylindrical structures under extreme underwater conditions. The recent Titan submersible implosion serves as a case study, highlighting the significance of rigorous design considerations. Key topics include material degradation, buckling instability, and material failure, with a detailed analysis of composite layup optimization and manufacturing processes such as filament winding and roll wrapping. The manuscript underscores the need for comprehensive testing, advanced simulation techniques, and monitoring system integration to ensure the safety and effectiveness of composite pressure hulls. Future research should focus on developing more accurate failure models, optimizing manufacturing processes, and enhancing material properties through innovations in composite science to realize the full potential of composite materials in deep-sea applications.

Suppressing burst risk of dome section in composite pressure vessels by contour-driven collaborative design

Composite pressure vessels are highly promising components of solid rocket motor casing, yet it has long been plagued by burst risk of dome section. Although current advances via the addition of composite layers can enhance dome strength, the weight redundancy still restricts the lightweight implementation. To this end, this paper presents an innovative contour-driven collaborative design for dome section, which helps suppress burst risk and avoid redundant weight due to composite layer thickening. Numerical burst assessment reveals that the pole size engenders a failure competition between pole and equator, indicating that rational utilization of this competition paves a feasible way for dome reinforcement. Besides, the burst risk is further suppressed by collaborative design between polar opening radius, polar boss size, and aspect ratio of ellipsoidal dome. Notably, it is concluded that greater polar boss size effectively reduces the stress concentration near pole, and rational manipulation of dome aspect ratio ensures compatible deformation near equator. More interestingly, we offer a collaborative design methodology to reinforce dome with various polar opening radii without thickening composite layers. This unique contour-driven collaborative design opens new avenues for simultaneous implementation of burst risk suppression and lightweight construction of composite pressure vessels.

Fibre misalignments in the split-disk test represented by random fields

Fibre misalignment is a major type of manufacturing defect in fibre-reinforced composite materials which has an adverse effect on the mechanical performance of composites. The present paper utilises stochastic models based on the random fields of fibre misalignment in the finite element analysis (FEA) of the split-disk test for filament wound composites. Local fibre misalignment characteristics are determined experimentally using X-ray micro-computed tomography (μ-CT) and then used to generate spatially correlated anisotropic random fields further mapped to finite element mechanical properties. The model predicts pronounced stress and strain non-homogeneity, an expected reduction in the overall modulus and pre-mature damage initiation. This leads to the evaluation of effect-of-defects and allowable for manufacturing tolerances in hoop layers of composite pressure vessels.

Deep transfer learning for efficient and accurate prediction of composite pressure vessel behaviors

Composite pressure vessels are manufactured by winding carbon fiber-reinforced plastic, while its performance is determined by fabrication conditions. To properly design composite pressure vessels, it is essential to analyze their behavior according to the design parameters. However, analytical or numerical methods have limitations in terms of accuracy or cost-effectiveness. In this study, a method is proposed to accurately and efficiently predict the behavior of composite pressure vessels through deep transfer learning. A prediction model is built by pre-training on a sufficient amount of analytical data, and then fine-tuning on a limited amount of numerical data. The performance of the deep transfer learning-based prediction model was evaluated through various error assessments. Its computational cost was also compared with that of finite element analysis. Furthermore, the deep transfer learning-based prediction model was used to analyze the impact of design parameters on the behavior of composite pressure vessels and for design optimization.

Effect of hollow glass microspheres on transverse properties of carbon fiber reinforced epoxy composites

AbstractHollow glass microsphere (HGM)—based composites are gaining popularity in materials research due to their ability in altering material characteristics drastically. The current study investigates HGMs filled carbon fiber reinforced epoxy (CE) composites on transverse properties, aiming for aerospace and defense applications mainly in composite pressure vessels. Unidirectional laminates of Carbon/Epoxy with varying HGM percentages (0.2, 0.4, 0.6, 0.8, 1.0 wt. %) were wounded onto a flat‐plate mandrel using a 4‐axis filament winder, along with a baseline sample without HGM for comparison. The glass transition temperature (Tg) and thermal stability were analyzed by carrying out dynamic mechanical analysis and thermogravimetric analysis. The fracture mechanism of the samples loaded under tension was investigated using FESEM. Experimental results indicate reduction in density with increase in HGM content, up to 0.4% HGM there is increase in transverse tensile strength of 25% compared to baseline and further increase in HGM content, decrease trend is observed. 30% decrease in transverse compressive strength is observed compared from baseline to 1.0 wt. % of HGM. No significant change was noticed in the thermal stability and Tg on introduction of HGM. Microscopy images of fractured samples revealed effective physical interaction and dispersion of the HGM within the matrix.Highlights Transverse mechanical properties are tested to know the influence of HGM filler on filament wound composites. Density of the composite decreases with increase in HGM content. Thermal stability and Tg shows less change on introduction of HGM in composites.

Composite Pressure Vessel Failure Simulation Considering Spatial Variability

Carbon fiber-reinforced polymers offer lightweight solutions for demanding applications, but material imperfections affect structural reliability. In this study, an efficient uncertainty propagation framework is applied to predict composite behavior. The framework accounts for spatial variability of fiber misalignment, uneven fiber distribution, and single-fiber strength. Spatial variability is represented at both the micro- and mesoscale. Macroscale simulations incorporate this spatial variability indirectly using homogenized material properties. The framework was applied to composite pressure vessels, whose stochastic burst pressure was predicted. The predictions were validated by experimental measurements. These measurements show that the actual burst pressure was underpredicted by an average of 5.8%. Several hypotheses were investigated to explain this discrepancy.