The Effects of Fluid Structure Interactions on the Dynamic Characteristics of the Reactor Internals Structure of SMART

The Korea Atomic Energy Research Institutes has been developing the SMART (System integrated Modular Advanced ReacTor), an environment-friendly nuclear reactor, for the generation of electricity, and to perform desalination. SMART reactors can be exposed to various external and internal loads caused by seismic and coolant flows. Reactor structures need to be maintained for the reactor’s safety and integrity against these loads during the operational time of the SMART. This paper presents two FE-models, 3-D solid models of the reactor internals in the air and in the coolant, and then compares the results of the dynamic characteristic for the two FE-models using a commercial Finite Element tool, ANSYS V12. A solver was selected by the Block Lanczos method. These FE-models are looking forward to being executed in various researches concerning the SMART in further studies.

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Ultrasound and Nonlinear Resonant Testing of Nuclear Reactor Internals Bolts

ASME 2011 Pressure Vessels and Piping Conference: Volume 5 ◽

10.1115/pvp2011-57077 ◽

2011 ◽

Cited By ~ 1

Author(s):

S. W. Glass ◽

B. Thigpen ◽

J. Renshaw

Keyword(s):

Phased Array ◽

Nuclear Reactor ◽

Structural Integrity ◽

Cost Effective ◽

Life Extension ◽

Safe Operation ◽

Plant Life ◽

Nuclear Plants ◽

Bolt Failure ◽

Reactor Internals

As many nuclear plants approach the end of their initial 40 year license period, inspection or replacement of their reactor internals bolts must be considered. This is consistent with the Materials Reliability Program (MRP 227/228) guideline for plant life extension [1,2]. Assurance of the internals structural integrity is essential for continued safe operation of these plants. If there is no suspicion or indication of bolt failure, simple inspection is normally more cost-effective than replacement. Inspection vendors have inspected thousands of internals bolts with conventional and Phased Array UT but different head configurations and bolt capture mechanisms mandate specific qualifications for each bolt type. In some cases, complex bolt and head geometries coupled with counter-bore and locking bar interferences render classical UT inspections difficult or impossible. A range of solutions to inspect reactor internals including these difficult-to-inspect-by-conventional-UT baffle bolts has been developed by several vendors [3]. This presentation references developments to make bolt inspection a relatively quick and easy task through adaptations to the SUSI submarine inspection platform, the extensive UT qualification work suitable for conventional UT plus more recent advanced nonlinear resonant techniques to distinguish between flawed or loose, vs. acceptable bolts where conventional UT cannot be applied. Initial evaluations show that these advanced techniques may have the ability to reliably detect smaller flaws than previously possible with conventional techniques as well as provide information on bolt tightness.

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A Block Lanczos Method for the CDT Subproblem

Journal of Computational Mathematics ◽

10.4208/jcm.1712-m2017-0064 ◽

2019 ◽

Vol 37 (2) ◽

pp. 240-260

Author(s):

Liqiang Song and Weihong Yang

Keyword(s):

Lanczos Method ◽

Block Lanczos ◽

Block Lanczos Method

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An Out-of-Core Eigen-Solver with OpenMP Parallel Scheme for Large Spare Damped System

International Journal of Computational Methods ◽

10.1142/s0219876219500385 ◽

2019 ◽

Vol 16 (07) ◽

pp. 1950038 ◽

Cited By ~ 1

Author(s):

S. H. Ju ◽

H. H. Hsu

Keyword(s):

Large Scale ◽

Block Size ◽

Lanczos Method ◽

Preconditioned Conjugate Gradient ◽

Damped System ◽

Parallel Scheme ◽

Complex Eigenvalues ◽

Lanczos Iteration ◽

Block Lanczos ◽

Block Lanczos Method

An out-of-core block Lanczos method with the OpenMP parallel scheme was developed to solve large spare damped eigenproblems. The symmetric generalized eigenproblem is first solved using the block Lanczos method with the preconditioned conjugate gradient (PCG) method, and the condensed damped eigenproblem is then solved to obtain the complex eigenvalues. Since the PCG solvers and out-of-core schemes are used, a large-scale eigenproblem can be solved using minimal computer memory. The out-of-core arrays only need to be read once in each Lanczos iteration, so the proposed method requires little extra CPU time. In addition, the second-level OpenMP parallel computation in the PCG solver is suggested to avoid using a large block size that often increases the number of iterations needed to achieve convergence.

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Dynamic Characteristics of a New Space Beam String Structure with Outer Truss Torus

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.1960 ◽

2012 ◽

Vol 588-589 ◽

pp. 1960-1963

Author(s):

Yun Long Yao ◽

Guang Ying Ma ◽

Shi Lin Dong

Keyword(s):

Dynamic Characteristics ◽

Lanczos Method ◽

Load Level ◽

Structure System ◽

System A ◽

Wind Vibration ◽

String Structure ◽

New Type ◽

New Space ◽

Block Lanczos Method

The large-span space beam string-structure system is a kind of economic and larger spanning spatial structure system. A new type of space beam-string-structure with outer truss torus is introduced. Sunflower-patterned space beam-string-structure was taken as an example and its dynamic characteristics under full-span load and half-span load were analyzed by block Lanczos method. The efect of prestress level and load level on dynamic behavior of the structure was studied. The results are valuable for the dynamic response research on the earthquakes and wind vibration and will provide a reference for a further design and project application of such structure.

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Essential and trace elements status in the indigenous Ethiopian tuber crops

Radiochimica Acta ◽

10.1515/ract-2018-3072 ◽

2019 ◽

Vol 108 (1) ◽

pp. 51-56

Author(s):

Tamene Hailu Melkegna ◽

Ashok Kumar Chaubey ◽

Sunday Adesunloye Jonah ◽

Yusuf Aminu Ahmed ◽

Nuruddeen Abubakar

Keyword(s):

Trace Elements ◽

International Organizations ◽

Nuclear Reactor ◽

Daily Intake ◽

Energy Research ◽

The Status ◽

Constituent Elements ◽

Essential And Trace Elements ◽

And Training ◽

Tuber Crops

Abstract The objective of the study is multi elemental analysis of four indigenous Ethiopian tuber crops using instrumental neutron activation analysis (INAA) technique in order to get scientific evidences about the status of essential, trace and non-essential elemental compositions. The samples were collected from Southern and South-western parts of Ethiopia. The irradiation and measurement were performed by using irradiation and counting facilities of the Nigeria Nuclear Reactor-1 (NIRR-1) and a HPGe detector setup at the Centre for Energy Research and Training (CERT), Ahmadu Bello University (ABU), Zaria, Nigeria. A total of 17 elements were determined at various concentration levels. The highest concentrations of K, Mg, Mn and Zn were found in Colocasia esculenta (L.) Schott, whereas; the concentrations of essential and trace elements; Ca, K, Mg, Na, Cl, Mn, and Zn were found to be high in the native Coccinia abyssinica (Lam.) Cogn tuber. The estimated daily intake values of the constituent elements from the consumption of these crops are below upper tolerable limits set by international organizations such as WHO and FAO.

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