Reactor physics verification of the MCNP6 unstructured mesh capability by Burke, T. P. (Department of Nuclear Engineering and Radiological Sciences, University
of Michigan, 2355 Bonisteel Boulevard, Ann Arbor, MI 48109 (United States)); Kiedrowski,
B. C.; Martz, R. L. (X-Computational Physics Division, Monte Carlo Codes Group, Los
Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States));
Martin, W. R. (Department of Nuclear Engineering and Radiological Sciences, University
of Michigan, 2355 Bonisteel Boulevard, Ann Arbor, MI 48109 (United States)) fromProceedings of the 2013 International Conference on Mathematics and Computational
Methods Applied to Nuclear Science and Engineering - M and C 2013 Read MoreCollapse
[en]
The Monte Carlo software package MCNP6 has the ability to transport particles on unstructured
meshes generated from the Computed-Aided Engineering software Abaqus. Verification
is performed using benchmarks with features relevant to reactor physics - Big Ten
and the C5G7 computational benchmark. Various meshing strategies are tested and results
are compared to reference solutions. Computational performance results are also given.
The conclusions show MCNP6 is capable of producing accurate calculations for reactor
physics geometries and the computational requirements for small lattice benchmarks
are reasonable on modern computing platforms. (authors)$$$$
A method for reducing the largest relative errors in Monte Carlo iterated-fission-source
calculations by Hunter, J. L. (Department of Nuclear Science and Engineering, Massachusetts Institute
of Technology, 77 Massachusetts Ave., 24-107, Cambridge, MA 02139 (United States));
Sutton, T. M. (Knolls Atomic Power Laboratory, Bechtel Marine Propulsion Corporation,
P. O. Box 1072, Schenectady, NY 12301-1072 (United States)) fromProceedings of the 2013 International Conference on Mathematics and Computational
Methods Applied to Nuclear Science and Engineering - M and C 2013 Read MoreCollapse
[en]
In Monte Carlo iterated-fission-source calculations relative uncertainties on local
tallies tend to be larger in lower-power regions and smaller in higher-power regions.
Reducing the largest uncertainties to an acceptable level simply by running a larger
number of neutron histories is often prohibitively expensive. The uniform fission
site method has been developed to yield a more spatially-uniform distribution of relative
uncertainties. This is accomplished by biasing the density of fission neutron source
sites while not biasing the solution. The method is integrated into the source iteration
process, and does not require any auxiliary forward or adjoint calculations. For a
given amount of computational effort, the use of the method results in a reduction
of the largest uncertainties relative to the standard algorithm. Two variants of the
method have been implemented and tested. Both have been shown to be effective. (authors)$$$$
The mathematical formulation of numerous physical problems a results in differential
equations actually partial or ordinary differential equations.In our study we are
interested in solutions of partial differential equations.The aim of this work is
to calculate the concentrations of the pollution, by solving the atmospheric diffusion
equation(ADE) using different mathematical methods of solution. It is difficult to
solve the general form of ADE analytically, so we use some assumptions to get its
solution.The solutions of it depend on the eddy diffusivity profiles(k) and the wind
speed u. We use some physical assumptions to simplify its formula and solve it. In
the present work, we solve the ADE analytically in three dimensions using Green's
function method, Laplace transform method, normal mode method and these separation
of variables method. Also, we use ADM as a numerical method. Finally, comparisons
are made with the results predicted by the previous methods and the observed data.$$$$
The objective of this procedure is to help the user to prepare an COMPSIS report on
an event so that important lessons learned are most efficiently transferred to the
database. This procedure focuses on the content of the information to be provided
in the report rather than on its format. The established procedure follows to large
extend the procedure chosen by the IRS incident reporting system. However this database
is built for I and C equipment with the purpose of the event report database to collect
and disseminate information on events of significance involving Computer-Based Systems
important to safety in nuclear power plants, and feedback conclusions and lessons
learnt from such events. For events where human performance is dominant to draw lessons,
more detailed guidance on the specific information that should be supplied is spelled
out in the present procedure. This guidance differs somewhat from that for the provision
of technical information, and takes into account that the engineering world is usually
less familiar with human behavioural analysis than with technical analysis. The events
to be reported to the COMPSIS database should be based on the national reporting criteria
in the participating member countries. The aim is that all reports including computer
based systems that meet each country reporting criteria should be reported. The database
should give a broad picture of events/incidents occurring in operation with computer
control systems. As soon as an event has been identified, the insights and lessons
learnt to be conveyed to the international nuclear community shall be clearly identified.
On the basis of the description of the event, the event shall be analyzed in detail
under the aspect of direct and potential impact to plant safety functions. The first
part should show the common involvement of operation and safety systems and the second
part should show the special aspects of I and C functions, hardware and software$$$$
Reports are on: - Measurement of Cross-Sections for Neutron Induced Reactions at 14
MeV. - Level Schemes and Gamma Ray Angular Distribution Measurements in ^{28}Si,
^{46}Ti, and ^{53}Mn. - A Study of Neutron-Induced Reaction ''1''2C
(n.n')3α at E_{n} =17.4 MeV. - A Study on Nuclear Evaporation in Nuclear Emulsion
Exposed to 3.0 GeV/c Mesons. - Spectroscopy of ^{64}Cu using the (^{3}He,p)
Reaction at 18 MeV.$$$$
Prognosis data on the production and consumption of electricity in Ukraine were used
to development of nuclear generation for Ukraine after 2030. The calculation was performed
using the MESSAGE computer code provided within Ukrainian activities in the IAEA INPRO
project, Assessments were carried out for the period till 2100 and for the open nuclear
fuel cycle (NFC) with advanced light-water reactors, partially closed NFC with CANDU
reactors and closed NFC with fast reactor$$$$
The mathematical and computer modeling of required operation modes of multipurpose
isochronous cyclotrons is presented. The considered procedure is based on the calculation
of currents in trim coils of correction of the main magnetic field (I_{i},
i = 1, 2...z) at a certain level of current in the main coil (I_{main}). A
series of numerical and physical experiments on modeling of the main operation mode
of the mutipurpose isochronous cyclotron AIC144 (INP PAS, Krakow): accelerated particles
are protons (p), extracted proton energy is E_{out} ∼ 60.3/60.7 MeV, RF-generator
frequency is F_{rf} = 26.155/26.25 MHz, confirmed both the necessity of including
the evaluation of solution stability into the calculation, and the possibility of
successful accelerating of the protons in the whole range of working radii with the
allowable phase losses of accelerated protons in the isochronization range of required
magnetic field (with decreasing beam current less than 50%) without stopping the cyclotron
for performing the additional magnetic measurements$$$$
Russian 2012 p. 48 Ukraine Stets, MV Pop, OM Maslyuk, VT Institut ehlektronnoj
fiziki NAN UKrainy, Uzhgorod (Ukraine ...$$$$ Orig. TitleRazrabotka algoritma pooucheniya soglasovannykh znachenij yadernykh konstant v raschetakh
tsepej radioaktivnogo raspada s povyshennoj tochnost'yu SubjectMATHEMATICAL METHODS AND COMPUTING (S97) Source/ReportNatsional'naya Akademiya Nauk Ukrainy, Kyiv (Ukraine); Natsional'nyj Nauchnyj Tsentr Khar'kovskij Fiziko-Tekhnicheskij Institut , Khar'kov
(Ukraine); Institut Fiziki Vysokikh Ehnergij i Yadernoj Fiziki, Khar'kov (Ukraine); 113 p; 2012; p. 48; 10. Conference on High Energy Physics, Nuclear Physics and Accelerators; Tezisy dokladov 10-j konferentsii po fizike vysokikh ehnergij, yadernoj fizike i uskoritelyam; Kharkov (Ukraine); 27 Feb - 2 Mar 2012; INIS-UA--189; Available from Ukrainian INIS Centre Record TypeMiscellaneous Country/Org.Ukraine DECCROSS SECTIONS, DECAY, MATHEMATICAL LOGIC, PARTICLE DECAY DEIALGORITHMS, CALCULATION METHODS, GROUP CONSTANTS, NUCLEAR DATA COLLECTIONS, RADIATIVE DECAY LanguageRussian Ref. Number45058773 Rel. Record45058714 Publ. Year2012 INIS Volume45 INIS Issue22
Multi-moment advection scheme in three dimension for Vlasov simulations of magnetized
plasma http://dx.doi.org/10.1016/j.jcp.2012.11.024 by Minoshima, Takashi (Institute for Research on Earth Evolution, Japan Agency for Marine-Earth
Science and Technology, 3173-25, Syowa-machi, Kanazawaku, Yokohama 236-0001 (Japan));
Matsumoto, Yosuke (Department of Physics, Chiba University, 1-33, Yayoi-cho, Inage-ku,
Chiba 263-8522 (Japan)); Amano, Takanobu (Department of Earth and Planetary Science,
University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)), E-mail: minoshim@jamstec.go.jp Read MoreCollapse
[en]
We present an extension of the multi-moment advection scheme [T. Minoshima, Y. Matsumoto,
T. Amano, Multi-moment advection scheme for Vlasov simulations, Journal of Computational
Physics 230 (2011) 6800–6823] to the three-dimensional case, for full electromagnetic
Vlasov simulations of magnetized plasma. The scheme treats not only point values of
a profile but also its zeroth to second order piecewise moments as dependent variables,
and advances them on the basis of their governing equations. Similar to the two-dimensional
scheme, the three-dimensional scheme can accurately solve the solid body rotation
problem of a gaussian profile with little numerical dispersion or diffusion. This
is a very important property for Vlasov simulations of magnetized plasma. We apply
the scheme to electromagnetic Vlasov simulations. Propagation of linear waves and
nonlinear evolution of the electron temperature anisotropy instability are successfully
simulated with a good accuracy of the energy conservation$$$$
In this letter, we present exact solutions of the Dirac equation with the mixed scalar-vector-pseudoscalar
spatially dependent mass Coulomb potential under spin and pseudospin (p-spin) symmetry
limits in 1+1 dimensions. (author)$$$$