Failure Fraction Calculation of the TRISO-Coated Particle Using X-Ray Computed Tomography

The geometrical shape of the TRISO-coated particle is closely related to its performance and safety. In this paper, models were set up to study the failure fraction of TRISO particle, considering the real asphericity induced by manufacturing uncertainties. TRISO is simplified as a pressure vessel model, and micro X-ray CT was employed to detect the real geometrical shape. Key geometrical parameters, thickness and volume of the real particle, were then obtained with the 3D measurement method and input into PANAMA code (a German code for fuel performance simulation). Release fraction of fission gas and failure fraction of the TRISO-coated particle were revised with the aforementioned parameters with more accuracy and compared with those of the spherical particle. Obvious increment of failure fraction of the particle is found, which may contribute to the release of fission products.

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Geometry and respiratory displacement of human ribs

Journal of Applied Physiology ◽

10.1152/jappl.1987.62.5.1872 ◽

1987 ◽

Vol 62 (5) ◽

pp. 1872-1877 ◽

Cited By ~ 47

Author(s):

T. A. Wilson ◽

K. Rehder ◽

S. Krayer ◽

E. A. Hoffman ◽

C. G. Whitney ◽

...

Keyword(s):

Three Dimensional ◽

Geometrical Parameters ◽

Small Component ◽

X Ray ◽

Lung Capacity ◽

Circular Arcs ◽

Residual Capacity ◽

X Ray Computed ◽

Best Fit ◽

Bucket Handle

The three-dimensional coordinates of points in the ribs of two supine relaxed males, holding their breath at functional residual capacity (FRC) and with their glottis closed at total lung capacity (TLC), were obtained from volumetric X-ray computed tomographical images. The orientation of planes that best fit the data for each rib at each lung volume and the circular arcs that fit the points in the planes of the ribs were determined, and average values of these geometrical parameters for ribs 3–7 are reported. The planes of the ribs at TLC can be described as displaced from the planes at FRC by a rotation about an axis that passes near the spine. The pump handle and bucket handle components of rotation are 11 and 13 degrees, respectively, for rib 3 and both decrease with increasing rib number to 7 and 10 degrees at rib 7. The angles between the axes of rotation and the midplane are approximately 35 degrees for all 5 ribs. The radii of the circular arcs fit to the data at TLC are slightly larger than those at FRC, and this suggests that there is a small component of rotation normal to the plane of the rib.

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Very Low-Intensity Throughput X-Ray Computed Tomography of a Cast FeMnAl Steel Alloy

Journal of Nondestructive Evaluation Diagnostics and Prognostics of Engineering Systems ◽

10.1115/1.4047065 ◽

2020 ◽

Vol 3 (4) ◽

Author(s):

William H. Green ◽

Bryan A. Cheeseman ◽

Daniel Field ◽

Krista R. Limmer

Keyword(s):

Computed Tomography ◽

Detector Response ◽

Steel Alloy ◽

Material Technology ◽

X Ray ◽

Low Intensity ◽

Combat Vehicle ◽

X Ray Computed ◽

Set Up ◽

Iron Manganese

Abstract The X-ray computed tomography (XCT) technique is a widely applicable and powerful non-destructive inspection modality for evaluation and analysis of geometrical and physical characteristics of materials, especially internal structures and features. XCT is applicable to metals, ceramics, plastics, and polymer and mixed composites, as well as components and materiel. The Army Research Laboratory (ARL) and its partners are currently investigating the use of cast iron-manganese-aluminum (FeMnAl) steel alloy material in support of weight reduction initiatives in Army Development Programs. Steel alloy FeMnAl has been identified as a key enabling material technology to reduce the weight in ground combat vehicle systems. A set of FeMnAl blocks each approximately 50.8 mm (2 in.) thick by 76.2 mm (3 in.) wide by 76.2 mm (3 in.) long, which had been sectioned from an industrially cast ingot (∼12,000 lbs.), were individually scanned by XCT using a conventional 450 kV X-ray source and a solid-state flat panel detector. Mainly due to the thickness of the blocks, as well as a desire to keep geometric unsharpness relatively small which affected overall scan geometry (set up), the scans had a very low response at the detector through the FeMnAl blocks. With the calibrated detector response through air (i.e., around a block) at 85–90% the response through the block was only 5–10%. The XCT scanning parameters and overall protocol used to mitigate the very low-intensity throughput and achieve acceptable scan image results will be discussed. Image processing (IP) methods used to segment porosity features in the FeMnAl blocks will also be discussed.

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A Method to Evaluate Fission Gas Release During Irradiation Testing of Spherical Fuel

Fourth International Topical Meeting on High Temperature Reactor Technology, Volume 1 ◽

10.1115/htr2008-58184 ◽

2008 ◽

Author(s):

Hanno van der Merwe ◽

Johan Venter

Keyword(s):

Fission Products ◽

Gas Release ◽

Fuel Performance ◽

Coated Particle ◽

Fission Gas ◽

Online Measurements ◽

Materials Used ◽

Fission Gas Release

The evaluation of fission gas release from spherical fuel during irradiation testing is critical to understand expected fuel performance under real reactor conditions. Online measurements of Krypton and Xenon fission products explain coated particle performance and contributions from graphitic matrix materials used in fuel manufacture and irradiation rig materials. Methods that are being developed to accurately evaluate fission gas release are described here together with examples of evaluations performed on irradiation tests HFR-K5, -K6 and EU1bis.

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First ptychographic X-ray computed tomography experiment on the NanoMAX beamline

Journal of Applied Crystallography ◽

10.1107/s160057672001211x ◽

2020 ◽

Vol 53 (6) ◽

pp. 1444-1451

Author(s):

Maik Kahnt ◽

Simone Sala ◽

Ulf Johansson ◽

Alexander Björling ◽

Zhimin Jiang ◽

...

Keyword(s):

Computed Tomography ◽

Imaging Technique ◽

Three Dimensional ◽

Scanning Speed ◽

Fourth Generation ◽

X Ray ◽

Radiation Sources ◽

X Ray Computed ◽

Synchrotron Light ◽

Set Up

Ptychographic X-ray computed tomography is a quantitative three-dimensional imaging technique offered to users of multiple synchrotron radiation sources. Its dependence on the coherent fraction of the available X-ray beam makes it perfectly suited to diffraction-limited storage rings. Although MAX IV is the first, and so far only, operating fourth-generation synchrotron light source, none of its experimental stations is currently set up to offer this technique to its users. The first ptychographic X-ray computed tomography experiment has therefore been performed on the NanoMAX beamline. From the results, information was gained about the current limitations of the experimental setup and where attention should be focused for improvement. The extracted parameters in terms of scanning speed, size of the imaged volume and achieved resolutions should provide a baseline for future users designing nano-tomography experiments on the NanoMAX beamline.

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A Method to Evaluate Fission Gas Release During Irradiation Testing of Spherical Fuel

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3097131 ◽

2009 ◽

Vol 131 (5) ◽

Cited By ~ 1

Author(s):

Hanno van der Merwe ◽

Johan Venter

Keyword(s):

Fission Products ◽

Gas Release ◽

Fuel Performance ◽

Coated Particle ◽

Fission Gas ◽

Online Measurements ◽

Materials Used ◽

Fission Gas Release

The evaluation of fission gas release from spherical fuel during irradiation testing is critical to understand expected fuel performance under real reactor conditions. Online measurements of krypton and xenon fission products explain coated particle performance and contributions from graphitic matrix materials used in fuel manufacture and irradiation rig materials. Methods that are being developed to accurately evaluate fission gas release are described here together with examples of evaluations performed on irradiation tests HFR-K5, -K6, and EU1bis.

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Reducing metal artifacts by restricting negative pixels

Visual Computing for Industry Biomedicine and Art ◽

10.1186/s42492-021-00083-z ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Gengsheng L. Zeng ◽

Megan Zeng

Keyword(s):

Computed Tomography ◽

Objective Function ◽

Ct Scans ◽

Filtered Backprojection ◽

Beam Hardening ◽

Metal Artifacts ◽

X Ray ◽

X Ray Computed ◽

Set Up ◽

True Values

AbstractWhen the object contains metals, its x-ray computed tomography (CT) images are normally affected by streaking artifacts. These artifacts are mainly caused by the x-ray beam hardening effects, which deviate the measurements from their true values. One interesting observation of the metal artifacts is that certain regions of the metal artifacts often appear as negative pixel values. Our novel idea in this paper is to set up an objective function that restricts the negative pixel values in the image. We must point out that the naïve idea of setting the negative pixel values in the reconstructed image to zero does not give the same result. This paper proposes an iterative algorithm to optimize this objective function, and the unknowns are the metal affected projections. Once the metal affected projections are estimated, the filtered backprojection algorithm is used to reconstruct the final image. This paper applies the proposed algorithm to some airport bag CT scans. The bags all contain unknown metallic objects. The metal artifacts are effectively reduced by the proposed algorithm.

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Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079176 ◽

1977 ◽

Vol 35 ◽

pp. 330-333

Author(s):

T. Gulik-Krzywicki ◽

M.J. Costello

Keyword(s):

Biological Materials ◽

Molecular Organization ◽

X Ray Diffraction ◽

Glass Capillary ◽

X Ray ◽

Rate Dependent ◽

Before And After ◽

Freeze Etching ◽

Diffraction Patterns ◽

Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

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