scholarly journals Proposal for a Fusion Prototype Neutron Source at the Los Alamos Neutron Science Center

2019 ◽  
Author(s):  
Eric John Pitcher ◽  
Yuri Konstantinovich Batygin ◽  
Stuart Andrew Maloy
2017 ◽  
Author(s):  
Karen Elizabeth Kippen
Keyword(s):  

2021 ◽  
Vol 5 (2) ◽  
pp. 12
Author(s):  
Matthew M. Schmitt ◽  
Daniel J. Savage ◽  
James J. Wall ◽  
John D. Yeager ◽  
Chanho Lee ◽  
...  

The US code of Federal Regulations mandates regular inspection of centrifugally cast austenitic stainless steel pipe, commonly used in primary cooling loops in light-water nuclear power plants. These pipes typically have a wall thickness of ~8 cm. Unfortunately, inspection using conventional ultrasonic techniques is not reliable as the microstructure strongly attenuates ultrasonic waves. Work is ongoing to simulate the behavior of acoustic waves in this microstructure and ultimately develop an acoustic inspection method for reactor inspections. In order to account for elastic anisotropy in the material, the texture in the steel was measured as a function of radial distance though the pipe wall. Experiments were conducted on two 10 × 12.7 × 80 mm radial sections of a cast pipe using neutron diffraction scans of 2 mm slices using the HIPPO time-of-flight neutron diffractometer at the Los Alamos Neutron Science Center (LANSCE, Los Alamos, NM, USA). Strong textures dominated by a small number of austenite grains with their (100) direction aligned in the radial direction of the pipe were observed. ODF analysis indicated that up to 70% of the probed volume was occupied by just three single-grain orientations, consistent with grain sizes of almost 1 cm. Texture and phase fraction of both ferrite and austenite phases were measured along the length of the samples. These results will inform the development of a more robust diagnostic tool for regular inspection of this material.


2013 ◽  
Vol 62 ◽  
pp. 05002 ◽  
Author(s):  
Fredrik Tovesson ◽  
Charles Arnold ◽  
Rick Blakeley ◽  
Adam Hecht ◽  
Alexander Laptev ◽  
...  

2017 ◽  
Vol 146 ◽  
pp. 04010 ◽  
Author(s):  
Fredrik Tovesson ◽  
Dmitriy Mayorov ◽  
Dana Duke ◽  
Brett Manning ◽  
Verena Geppert-Kleinrath

2020 ◽  
Vol 239 ◽  
pp. 01004
Author(s):  
Yaron Danon ◽  
Ezekiel Blain ◽  
Kumar Mohindroo ◽  
Matt Devlin ◽  
Keegan J.Kelly ◽  
...  

A neutron induced neutron emission experiment was conducted as the Los Alamos Neutron Science Center (LANSCE) facility at Los Alamos National Laboratory (LANL). In this experiment, a sample was placed in a well collimated neutron beam and was surrounded by an array of 28 fast neutron detectors (EJ-309). The experiment was performed with a neutron flight path of 21.5 m from the source to the sample, and 1 m from the sample to the detectors. The neutron emission from the sample was measured as a function of neutron time of flight covering an incident energy range from 0.7- 20 MeV. The samples included U-235, Pu-239, carbon (graphite), and blanks that matched the encapsulation of the sample. The measured samples were constantly cycled in and out of the neutron beam. This type of experiment measures neutron emission from all reactions occurring in the sample such as fission and elastic and inelastic scattering. Similar to the methodology previously developed at RPI [1], the measurements were compared with detailed simulations of the experiment using different cross section evaluations for the sample. The observed differences can be attributed to the evaluated neutron cross section and angular distributions. The carbon sample was used as a reference to validate both the experiment and simulation methodology and showed good agreement between experiments and simulations. A review of the experimental setup, analysis methods, and some of the results will be presented.


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