Research on Defect Detection of Fully-Wrapped Carbon Fiber Reinforced Hydrogen Storage Cylinder With an Aluminum Liner by Industrial Computed Tomography

Abstract

Currently, on-board storage cylinders of compressed hydrogen for land vehicles primarily use fully-wrapped carbon fiber reinforced cylinders with an aluminum liner. Due to the multi-layer structure of the hydrogen storage cylinder, nondestructive testing of the cylinder is facing great challenges and the nondestructive testing methods given in the standard are mainly internal and external surface testing by using visual inspection or an endoscope, causing that many internal defects cannot be identified. Industrial computed tomography is able to intuitively display three-dimensional information of the examined object, and thus this technology is expected to detect internal defects of the cylinders. In this study, the loading system of the cylinder, including limit plates, support blocks and support columns, was designed and manufactured. The industrial computed tomography test method with the use of a filter was established, and the delamination defects at the cylinder neck, shoulder, and cylindrical shell were systematically researched. It was found that the delamination defect width at the neck was the largest, followed by the defect width at the shoulder, and the defect width at the cylindrical shell was the smallest. In addition, the whole cylinder was detected by using spiral scan, demonstrating that this test method had the potential to be a common tool to monitor the cylinder defects.

Research on defect detection and wall thickness analysis of fully-wrapped carbon fiber reinforced hydrogen storage cylinder for unmanned aerial vehicles by industrial computed tomography

“…Using industrial CT analysis software (VGSTUDIO MAX), the wall thickness of the Al liner and carbon fiber layer were measured to be approximately 1.5 mm and 4.5 mm, respectively. Comparing hydrogen storage cylinders for land vehicles and UAVs [9], it was found that the wall thickness of Al liner and carbon fiber layer of UAVs was much smaller than that of land vehicles, where the average wall thickness of Al liner and carbon fiber layer at the cylindrical shell with 35 MPa working pressure was about 5.5 mm and 21.0 mm, respectively. The thin-walled thickness of Al liner and carbon fiber layer put forward higher requirements for the dimensional processing accuracy of UAV hydrogen storage cylinders.…”

“…Industrial computed tomography (CT) technology can provide information on the distribution of the linear attenuation coefficient inside the tested object, enabling intuitive defect detection and size measurement [ 4 , 5 ]. This testing technology has been applied in the aerospace and transportation fields, such as wall thickness measurement of engine hollow blades and defect detection of fully-wrapped carbon fiber reinforced hydrogen storage cylinder for land vehicles [6][7][8][9]. Wang et al studied the wall thickness measurement method of aero-engine hollow turbine blades by using industrial CT [7], indicating that the industrial CT technique could be employed to measure the wall thickness of aerospace engine turbine blades.…”

“…Nebe et al found delamination defects in the high strain area of the hydrogen storage cylinder with plastic liner [8], which was concluded to further contributed to preliminary failure. Shi et al conducted industrial CT tests on hydrogen storage cylinder with Aluminum (Al) liner for land vehicles and systematically research the delamination defects at the cylinder neck, shoulder, and cylindrical shell [9]. The above literature analysis indicated that the industrial CT technology was expected to be a useful tool for defect detection and wall thickness analysis of hydrogen storage cylinders for UAVs.…”

A Dilated Residual Network for Turbine Blade ICT Image Artifact Removal

“…ICT (Industrial Computed Tomography) has been widely used in defect detection [ 1 , 2 , 3 , 4 , 5 ], dimensional measurements [ 6 , 7 ], and geometric analysis [ 8 , 9 ], including in the aerospace field [ 5 , 10 ], vehicle manufacturing [ 11 , 12 ], additive manufacturing [ 3 , 5 , 8 ], etc. However, due to the influence of beam hardening and scattering during CT scanning and imaging, there are artifacts on the obtained cross-section images, as illustrated in Figure 1 .…”

Study on creep cavity morphology of P91 power plant steel by industrial computed tomography

“…Creep cavities appear in the initial creep stage, so the residual creep life can be analyzed according to the size and distribution of creep cavities [9]. Industrial computed tomography (CT) is an effective means of nondestructive testing, widely used in aerospace, transportation, electron materials and other fields [10]. Compared with other nondestructive testing methods, such as radiographic and ultrasonic testing, industrial CT can directly reconstruct the three-dimensional internal structure of the measured object, and obtain two-dimensional images of defects with high dimensional measurement accuracy.…”