A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients

Trahan, Travis John

doi:10.1016/j.anucene.2018.11.055

Title: A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients

Full Record
Other Related Research

Abstract

A pseudo-time-dependent Monte Carlo algorithm suitable for simulating thermal reactor transients with timescales on the order of seconds is presented. An initial experimental implementation has been written into the Monte Carlo Application ToolKit (MCATK) developed at Los Alamos National Laboratory. The algorithm is essentially a combination of the fully time-dependent Monte Carlo algorithm, including the explicit simulation of delayed neutron precursors, and a quasi-static algorithm that does not use the point-kinetics equations. The fully time-dependent calculation is performed for some number of inactive and active micro time steps. The dynamic reactor time constant and delayed neutron precursor production rates are calculated directly from the active cycles, rather than from point-kinetics parameters. These quantities are then used to advance the neutron population and delayed neutron precursors forward in time across a macro time step. As a result, the method is applied to the C5G7-TD benchmark operating in steady state and in transient mode.

Authors:

Trahan, Travis John ^[1]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: 2018-12-19

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1494480

Report Number(s):: LA-UR-18-28351
Journal ID: ISSN 0306-4549

Grant/Contract Number:: 89233218CNA000001

Resource Type:: Accepted Manuscript

Journal Name:: Annals of Nuclear Energy (Oxford)

Additional Journal Information:: Journal Name: Annals of Nuclear Energy (Oxford); Journal Volume: 127; Journal Issue: C; Journal ID: ISSN 0306-4549

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; Monte Carlo Time-dependent Quasi-static Reactor transient Delayed neutrons

Citation Formats


                    Trahan, Travis John. A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients.  United States: N. p., 2018. 
        Web.  doi:10.1016/j.anucene.2018.11.055.

Copy to clipboard


                    Trahan, Travis John. A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients.  United States.  doi:https://doi.org/10.1016/j.anucene.2018.11.055

Copy to clipboard


                    Trahan, Travis John. Wed .  
        "A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients".  United States.  doi:https://doi.org/10.1016/j.anucene.2018.11.055.  https://www.osti.gov/servlets/purl/1494480.

Copy to clipboard


                    
@article{osti_1494480,

  title        = {A quasi-static Monte Carlo algorithm for the simulation of sub-prompt critical transients},

  author       = {Trahan, Travis John},

  abstractNote = {A pseudo-time-dependent Monte Carlo algorithm suitable for simulating thermal reactor transients with timescales on the order of seconds is presented. An initial experimental implementation has been written into the Monte Carlo Application ToolKit (MCATK) developed at Los Alamos National Laboratory. The algorithm is essentially a combination of the fully time-dependent Monte Carlo algorithm, including the explicit simulation of delayed neutron precursors, and a quasi-static algorithm that does not use the point-kinetics equations. The fully time-dependent calculation is performed for some number of inactive and active micro time steps. The dynamic reactor time constant and delayed neutron precursor production rates are calculated directly from the active cycles, rather than from point-kinetics parameters. These quantities are then used to advance the neutron population and delayed neutron precursors forward in time across a macro time step. As a result, the method is applied to the C5G7-TD benchmark operating in steady state and in transient mode.},

  doi          = {10.1016/j.anucene.2018.11.055},

  journal      = {Annals of Nuclear Energy (Oxford)},

  number       = C,

  volume       = 127,

  place        = {United States},

  year         = {2018},

  month        = {12}

}

Copy to clipboard

Journal Article:

Free Publicly Available Full Text

Accepted Manuscript (DOE)

Publisher's Version of Record

DOI: https://doi.org/10.1016/j.anucene.2018.11.055

Other availability

Search WorldCat to find libraries that may hold this journal

Save / Share:

Export Metadata

Save to My Library

Similar Records in DOE PAGES and OSTI.GOV collections:

Nuclear reactor transient analysis via a quasi-static kinetics Monte Carlo method

Journal Article Jo, YuGwon ; Cho, Bumhee ; Cho, Nam Zin, E-mail: nzcho@kaist.ac.kr - AIP Conference Proceedings

The predictor-corrector quasi-static (PCQS) method is applied to the Monte Carlo (MC) calculation for reactor transient analysis. To solve the transient fixed-source problem of the PCQS method, fission source iteration is used and a linear approximation of fission source distributions during a macro-time step is introduced to provide delayed neutron source. The conventional particle-tracking procedure is modified to solve the transient fixed-source problem via MC calculation. The PCQS method with MC calculation is compared with the direct time-dependent method of characteristics (MOC) on a TWIGL two-group problem for verification of the computer code. Then, the results on a continuous-energy problemmore » are presented.« less
DOI: https://doi.org/10.1063/1.4938774
Burst wait time simulation of CALIBAN reactor at delayed super-critical state

Conference Humbert, P. ; Authier, N. ; Richard, B. ; ...

In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present themore »« less
Development of Transient Capabilities for the NEAMS Neutronics Code PROTEUS

Technical Report Yang, Won Sik ; Downar, Thomas ; Hsieh, Albert ; ...

Transient calculation capabilities for the NEAMS three-dimensional (3-D) transport neutronics code PROTEUS have been developed to expand its applicability to a wider range of analyses for different types of reactors. The precursor integration technique was used to convert the time-dependent transport equation to a fixed source problem and two general categories of transient solvers were implemented to solve the transient fixed source problem (TFSP). The first method solves the TFSP iteratively using the 3-D transport solver in PROTEUS and the second method factorizes the time-dependent angular flux into a slowly changing shape function and a more rapidly changing amplitude function.more »« less
DOI: https://doi.org/10.2172/1581446

Full Text Available
Collision of Physics and Software in the Monte Carlo Application Toolkit (MCATK)

Technical Report Sweezy, Jeremy Ed

The topic is presented in a series of slides organized as follows: MCATK overview, development strategy, available algorithms, problem modeling (sources, geometry, data, tallies), parallelism, miscellaneous tools/features, example MCATK application, recent areas of research, and summary and future work. MCATK is a C++ component-based Monte Carlo neutron-gamma transport software library with continuous energy neutron and photon transport. Designed to build specialized applications and to provide new functionality in existing general-purpose Monte Carlo codes like MCNP, it reads ACE formatted nuclear data generated by NJOY. The motivation behind MCATK was to reduce costs. MCATK physics involves continuous energy neutron & gammamore »« less
DOI: https://doi.org/10.2172/1237224

Full Text Available
Analytical applications for delayed neutrons

Conference Eccleston, G W

Analytical formulations that describe the time dependence of neutron populations in nuclear materials contain delayed-neutron dependent terms. These terms are important because the delayed neutrons, even though their yields in fission are small, permit control of the fission chain reaction process. Analytical applications that use delayed neutrons range from simple problems that can be solved with the point reactor kinetics equations to complex problems that can only be solved with large codes that couple fluid calculations with the neutron dynamics. Reactor safety codes, such as SIMMER, model transients of the entire reactor core using coupled space-time neutronics and comprehensive thermal-fluidmore »« less
Full Text Available

Similar Records