Analysis of Fiber Glass/Vinyl Ester Composite Subjected to Internal Pressure Loading for Compressed Natural Gas (CNG) Tube Type IV Application

Natural gas in the form of compressed natural gas (CNG) has a pressure of 20 MPa. Glass fiber/vinyl ester composite has potential to be formed into a CNG tube. This study uses a numerical analysis method and tubular approching to assess composite ability to accept internal pressure loading, refered to failure criteria Tsai-Hill. The number of layers and fiber direction are chosen as independent variable. Configuration angle (+70, +25) provided a more optimal result than using a single angle. Composites are in a safe condition on 180th layer. Thus, the glass fiber composite material / vinyl ester is not recommended to apply in the CNG tube manufacture.

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Analysis of a Fiber Composite Cylinder Laminated with an Elastic-Plastic Aluminum Liner under Internal Pressure Loading

Journal of Thermoplastic Composite Materials ◽

10.1177/089270579801100506 ◽

1998 ◽

Vol 11 (5) ◽

pp. 466-477

Author(s):

Stephen R. Swanson ◽

Matt Offolter

Keyword(s):

Internal Pressure ◽

Fiber Composite ◽

Composite Cylinder ◽

Pressure Loading ◽

Elastic Plastic

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Interlaminar/interfiber failure of unidirectional glass fiber reinforced composites used for wind turbine blades

Journal of Composite Materials ◽

10.1177/0021998312440132 ◽

2012 ◽

Vol 47 (3) ◽

pp. 353-368 ◽

Cited By ~ 11

Author(s):

Martin Leong ◽

Lars CT Overgaard ◽

Isaac M Daniel ◽

Erik Lund ◽

Ole T Thomsen

Keyword(s):

Glass Fiber ◽

Turbine Blades ◽

Axial Loading ◽

Strain Curve ◽

Failure Criteria ◽

Image Correlation ◽

Fiber Direction ◽

Stress Strain ◽

Failure Initiation ◽

Unidirectional Glass

A unidirectional glass fiber/epoxy composite was characterized under multi-axial loading by testing off-axis specimens under uniaxial tension and compression at various angles relative to the fiber direction. Iosipescu shear tests were performed with both symmetric and asymmetric specimens. Tests were performed on both 1-2 and 1-3 material coordinate planes. Strain gauges and Digital Image Correlation were used to record the stress–strain responses. A new approach was used to define a ‘failure initiation strength’ by analyzing the recorded stress–strain curves. The experimentally determined failure stresses were compared with the predictions of the maximum stress, Tsai-Wu and Northwestern University failure criteria. It was found that using the approach of analyzing the stress–strain curve to define a point of material failure initiation, it was possible to obtain good correlation between the experimental data and predictions by both the Tsai-Wu and the NU failure criteria.

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Structural Design and Stress Analysis of a Fully-Wrapped Composite CNG Gas Cylinder With Nominal Working Pressure of 30 MPa

Volume 3: Design and Analysis ◽

10.1115/pvp2020-21521 ◽

2020 ◽

Author(s):

Xiaoqiang Qin ◽

Lin Liang ◽

Xiaobing Zhang ◽

Guide Deng ◽

Haifeng Liang

Keyword(s):

Natural Gas ◽

Stress Analysis ◽

Structural Design ◽

Fiber Composite ◽

Working Pressure ◽

Compressed Natural Gas ◽

Gas Cylinder ◽

Helical Winding ◽

Steel Liner ◽

Autofrettage Pressure

Abstract China is the world’s largest user of compressed natural gas vehicles, with a total of nearly 6 million compressed natural gas (CNG) vehicles. The nominal working pressure of the cylinders used in the CNG vehicles in China is 20 MPa, as a result, CNG vehicles have a short range. In order to improve the range of CNG vehicles, the development of CNG vehicles with higher pressure is promoted by the CNG vehicle industry in China nowadays. In this paper, structural design of a fully-wrapped composite CNG gas cylinder with nominal working pressure of 30 MPa are carried out. The steel liner is made of 4130X seamless steel with design wall thickness of 5.9 mm, and the outer surface of steel liner is wrapped with resin based glass fiber composite material. The fully-wrapped composite adopts mixed fiber winding mode: low-angle helical winding, high-angle helical winding and hoop winding. Stress analysis and autofrettage pressure optimization of the designed composite gas cylinder are carried out with finite element method. The results show that the designed composite gas cylinder meets the requirements of ISO 11439-2013, and the best autofrettage pressure of the gas cylinder is 52 MPa after optimizing the autofrettage pressure.

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