Jaakko Leppänen

20062019
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Research Output 2006 2019

2019
1 Citation (Scopus)
Spatial distribution
Monte Carlo simulation
43 Downloads (Pure)

A Review of District Heating Reactor Technology

Leppänen, J., 10 Jan 2019, VTT Technical Research Centre of Finland. 14 p. (Lappeenranta University of Technology: Department of Information Technology. Research report; No. VTT-R-06895-18).

Research output: Book/ReportReportProfessional

Open Access
File
District heating
Heating
Biofuels
Nuclear reactors
Fossil fuels

New energy deposition treatment in the Serpent 2 Monte Carlo transport code

Tuominen, R., Valtavirta, V. & Leppänen, J., 2019, In : Annals of Nuclear Energy. 129, p. 224-232 9 p.

Research output: Contribution to journalArticleScientificpeer-review

Neutrons
Photons
Detectors

Response Matrix Method–Based Importance Solver and Variance Reduction Scheme in the Serpent 2 Monte Carlo Code

Leppänen, J., 30 Apr 2019, In : Nuclear Technology. 18 p.

Research output: Contribution to journalArticleScientificpeer-review

Photons
mesh
Neutron sources
Subroutines
matrices

Serpent/SCF pin-level multiphysics solutions for the VERA Fuel Assembly benchmark

Ferraro, D., Garcia, M., Imke, U., Valtavirta, V., Leppänen, J. & Sanchez-Espinoza, V., 9 Jan 2019, In : Annals of Nuclear Energy. 128, p. 102-114 13 p.

Research output: Contribution to journalArticleScientificpeer-review

Nuclear industry
Nuclear reactors
Coolants
Physics
Innovation
2018
3 Citations (Scopus)

Advancement of functional expansion capabilities: Implementation and optimization in Serpent 2

Wendt, B., Kerby, L., Tumulak, A. & Leppänen, J., 1 Aug 2018, In : Nuclear Engineering and Design. 334, p. 138-153 16 p.

Research output: Contribution to journalArticleScientificpeer-review

optimization
Astronomical Netherlands Satellite
expansion
evaluation
mesh

Application of the Serpent–OpenFOAM Coupled Code System to the SEALER Reactor Core

Tuominen, R., Valtavirta, V. & Leppänen, J., 2018, Proceedings of PHYSOR 2018.

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsProfessional

reactor cores
charge flow devices
physics
liquid metals
files

Applications of Serpent 2 Monte Carlo Code to ITER Neutronics Analysis

Turner, A., Burns, A., Colling, B. & Leppänen, J., 17 Nov 2018, In : Fusion Science and Technology. 74, 4, p. 315-320 6 p.

Research output: Contribution to journalArticleScientificpeer-review

Geometry
blankets
geometry
requirements
vessels

Assessment of Serpent Cross Sections of the Second Generation Fuel of TVEL for Loviisa NPP

Kuopanportti, J., Leppänen, J. & Saarinen, S., 2018, (Accepted/In press) Proceedings of the PHYSOR 2018, Cancun, Mexico. American Nuclear Society ANS

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

2 Citations (Scopus)

Calculation chain for the analysis of spent nuclear fuel in long-term interim dry storage

Arkoma, A., Huhtanen, R., Leppänen, J., Peltola, J. & Pättikangas, T., 22 Apr 2018, In : Annals of Nuclear Energy. 119, p. 129–138 10 p.

Research output: Contribution to journalArticleScientificpeer-review

Spent fuels
Nuclear fuels
Computational fluid dynamics
Physics
Unloading

Collision-history based sensitivity/perturbation calculation capabilities in Serpent 2.1.30

Valtavirta, V., Aufiero, M. & Leppänen, J., 2018. 12 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Maintainability

Development of a spatial domain decomposition scheme for Monte Carlo neutron transport

García, M., Ferraro, D., Sanchez-Espinoza, V. H., Mercatali, L., Leppänen, J. & Valtavirta, V., Nov 2018, 26th International Conference on Nuclear Engineering: Nuclear Fuel and Material, Reactor Physics, and Transport Theory. American Society of Mechanical Engineers ASME, Vol. 3. 7 p. ICONE26-82144

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Neutrons
Decomposition
Data storage equipment
Scalability
Geometry

Effects of fuel temperature history approximations on neutronics properties of a BWR assembly

Valtavirta, V. & Leppänen, J., 2018, (Accepted/In press) Proceedings of the PHYSOR 2018, Cancun, Mexico. American Nuclear Society ANS, p. 2215-2226 12 p.

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Boiling water reactors
Actinides
Temperature
Gadolinium
Isotopes
1 Citation (Scopus)

Foreseen capabilities, bottlenecks identification and potential limitations of serpent MC transport code in large-scale full 3-D burnup calculations

Ferraro, D., Garcia, M., Mercatali, L., Sanchez Espinoza, V. H., Leppänen, J. & Valtavirta, V., Nov 2018, 26th International Conference on Nuclear Engineering: Nuclear Fuel and Material, Reactor Physics, and Transport Theory. American Society of Mechanical Engineers ASME, Vol. 3. 9 p. ICONE26-82305

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Nuclear reactors
Nuclear industry
Parallel architectures
Reactor cores
Screening

New stochastic substep based burnup scheme for Serpent 2

Valtavirta, V. & Leppänen, J., 2018, (Accepted/In press) Proceedings of PHYSOR 2018, Cancun, Mexico. American Nuclear Society ANS, p. 523-534

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Gadolinium
Feedback
1 Citation (Scopus)

SERPENT validation and optimization with mesh adaptive search on stereolithography geometry models

Talamo, A., Gohar, Y. & Leppänen, J., 1 May 2018, In : Annals of Nuclear Energy. 115, p. 619-632 14 p.

Research output: Contribution to journalArticleScientificpeer-review

Stereolithography
Geometry
3D printers
Research reactors
Computer programming languages
2017
1 Citation (Scopus)

Advancement of functional expansion tallies capabilities in serpent 2

Wendt, B. L., Kerby, L. M., Tumulak, A. G., Leppänen, J. I. & Dehart, M. D., 1 Jan 2017, In : Transactions of the American Nuclear Society. 116, p. 552-555 4 p.

Research output: Contribution to journalArticle in a proceedings journalScientificpeer-review

Open Access

Coupled burnup calculations with the serpent 2 Monte Carlo code

Valtavirta, V. & Leppänen, J., 2017. 12 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
Temperature distribution
Isotopes
Paramagnetic resonance
Feedback
Temperature
5 Citations (Scopus)

Coupled neutronics-fuel behavior calculations in steady state using the Serpent 2 Monte Carlo code

Valtavirta, V., Leppänen, J. & Viitanen, T., 2017, In : Annals of Nuclear Energy. 100, Part 2, p. 50-64 15 p.

Research output: Contribution to journalArticleScientificpeer-review

Physics
Temperature distribution
Feedback
Temperature
Geometry

Development of a coupled neutron / photon transport mode in the serpent 2 Monte Carlo code

Leppänen, J., Kaltiaisenaho, T., Valtavirta, V. & Metsälä, M., 2017. 6 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
neutrons
photons
methodology
radiation shielding
heating

Development of a Monte Carlo based calculation sequence for reactor core safety analyses (MONSOON)

Leppänen, J., 2017, SAFIR2018 - The Finnish Research Programme on Nuclear Power Plant Safety 2015-2018: Interim Report. VTT Technical Research Centre of Finland, p. 175-185 (VTT Technology, Vol. 294).

Research output: Chapter in Book/Report/Conference proceedingChapter or book articleProfessional

Open Access

Development of a variance reduction scheme in the serpent 2 Monte Carlo code

Leppänen, J., Viitanen, T. & Hyvönen, O., 2017. 7 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
Radiation shielding
Spent fuels
Dosimetry
Neutrons
Fusion reactions

Estimating the effects of homogenized fuel temperature in group constant generation using Serpent 2

Valtavirta, V. & Leppänen, J., 1 Jul 2017, In : Annals of Nuclear Energy. 105, p. 79-94 16 p.

Research output: Contribution to journalArticleScientificpeer-review

Isotopes
Paramagnetic resonance
Physics
Temperature
Gadolinium

Implementation of weighted delta-tracking with scattering in the serpent 2 monte carlo code

Rehak, J. S., Kerby, L. M., Dehart, M. D., Slaybaugh, R. N. & Leppänen, J., 1 Jan 2017, 2017 Annual Meeting. American Nuclear Society ANS, Vol. 116. p. 548-551 4 p. (Transactions of the American Nuclear Society, Vol. 116).

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Open Access

MCNP6 and SERPENT2 performances with unstructured mesh geometry

Talamo, A., Gohar, Y. A. & Leppänen, J., 1 Jan 2017, In : Transactions of the American Nuclear Society. 116, 2, p. 1111-1113 3 p.

Research output: Contribution to journalArticle in a proceedings journalScientificpeer-review

Open Access

New approaches and applications for Monte Carlo perturbation theory

Aufiero, M., Bidaud, A., Kotlyar, D., Leppänen, J., Palmiotti, G., Salvatores, M., Sen, S., Shwageraus, E. & Fratoni, M., 2017. 8 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
perturbation theory
methodology
perturbation
energy

Nuclear criticality and safety analyses preparedness at VTT (KATVE)

Juutilainen, P., Dorval, E., Huhtanen, R., Leppänen, J., Räty, A., Häkkinen, S., Kaltiaisenaho, T., Kotiluoto, P., Peltola, J., Rantamäki, K., Valtavirta, V., Tuominen, R. & Viitanen, T., 2017, SAFIR2018 - The Finnish Research Programme on Nuclear Power Plant Safety 2015-2018: Interim Report. VTT Technical Research Centre of Finland, p. 162-174 (VTT Technology, Vol. 294).

Research output: Chapter in Book/Report/Conference proceedingChapter or book articleProfessional

Open Access
3 Citations (Scopus)

On the use of delta-tracking and the collision flux estimator in the Serpent 2 Monte Carlo particle transport code

Leppänen, J., 1 Jul 2017, In : Annals of Nuclear Energy. 105, p. 161-167 7 p.

Research output: Contribution to journalArticleScientificpeer-review

Fluxes
Physics
Reaction rates
Fusion reactions
Radiation

Preliminary serpent-MOOSE coupling and implementation of functional expansion tallies in serpent

Kerby, L., Tumulak, A., Leppänen, J. & Valtavirta, V., 2017. 4 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
Bins
Nuclear reactors
Hydraulics
Data storage equipment
Hot Temperature

SERPENT performance with hybrid combinatorial and stereolithographic geometry

Talamo, A., Gohar, Y. & Leppänen, J., 2017. 7 p.

Research output: Contribution to conferenceConference articleScientificpeer-review

Open Access
Geometry
Stereolithography

The precursor-based delayed neutrons emission model applied to a water level transient

Talamo, A., Gohar, Y., Leppänen, J. & Valtavirta, V., 2017, In : Transactions of the American Nuclear Society. 117, p. 1290-1291 3 p.

Research output: Contribution to journalArticle in a proceedings journalScientificpeer-review

2016

Calculating neutron dosimeter activation in VVER-440 surveillance chains with Serpent

Viitanen, T. & Leppänen, J., 2016, 26th Symposium of AER on VVER Reactor Physics and Reactor Safety : Book of Abstracts. p. 181-188

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

surveillance
dosimeters
pressure vessels
activation
reactors
5 Citations (Scopus)

Coupling Serpent and OpenFOAM for neutronics - CFD multi-physics calculations

Tuominen, R., Valtavirta, V., Peltola, J. & Leppänen, J., 2016, PHYSOR 2016: Unifying Theory and Experiments in the 21st Century. American Nuclear Society ANS, p. 255-269

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Open Access
charge flow devices
boiling
physics
density distribution
temperature distribution
5 Citations (Scopus)

Expanding the Use of Serpent 2 to Fusion Applications: Shut-down Dose Rate Calculations

Leppänen, J. & Kaltiaisenaho, T., 2016, Proceedings of PHYSOR 2016. American Nuclear Society ANS

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

5 Citations (Scopus)

Expanding the use of Serpent 2 to Fusion Applications: Development of a Plasma Neutron Source

Sirén, P. & Leppänen, J., 2016, PHYSOR 2016: Unifying Theory and Experiments in the 21st Century. American Nuclear Society ANS

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Mesh Adaptive Search Optimization in SERPENT2 Stereolithography Geometry

Talamo, A., Gohar, Y. A. & Leppänen, J., 2016, In : Transactions of the American Nuclear Society. 115, p. 1127-1129

Research output: Contribution to journalArticle in a proceedings journalScientificpeer-review

Multiphysics simulation of fast transients with the FINIX fuel behaviour module

Ikonen, T., Syrjälahti, E., Valtavirta, V., Loukusa, H., Leppänen, J. & Tulkki, V., 8 Sep 2016, In : EPJ Nuclear Sciences & Technologies. 2, 8 p., 37.

Research output: Contribution to journalArticleScientificpeer-review

Open Access
Physics
Control rods
Accidents
Hydraulics
Feedback

Neutronic Assessment of TRISO Particle Fuels in a Small Fluoride Salt-cooled High-temperature Reactor

Mohamed, H., Lindley, B., Parks, G. & Leppänen, J., 2016, Proceedings of PHYSOR 2016. American Nuclear Society ANS

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

5 Citations (Scopus)

New Interpolation Capabilities for Thermal Scattering Data in Serpent 2

Viitanen, T. & Leppänen, J., 2016, PHYSOR 2016: Unifying Theory and Experiments in the 21st Century. cd-rom ed. American Nuclear Society ANS

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

28 Citations (Scopus)

Overview of methodology for spatial homogenization in the Serpent 2 Monte Carlo code

Leppänen, J., Pusa, M. & Fridman, E., 2016, In : Annals of Nuclear Energy. 96, p. 126-136

Research output: Contribution to journalArticleScientificpeer-review

Parameterization
Neutrons
Simulators
Scattering
Defects

Serpent Monte Carlo -reaktorifysiikkakoodin kehitys

Leppänen, J., 2016, In : ATS Ydintekniikka. 45, 3, p. 65-69

Research output: Contribution to journalArticleProfessional

1 Citation (Scopus)

Validating the Serpent Model of FiR 1 Triga Mk-II Reactor by Means of Reactor Dosimetry

Viitanen, T. & Leppänen, J., 2016, In : EPJ Web of Conferences. p. 8

Research output: Contribution to journalArticleScientificpeer-review

Open Access
estimators
dosimeters
reactors
reaction kinetics
reactor physics
10 Citations (Scopus)

Validation of the Serpent-ARES code sequence using the MIT BEAVRS benchmark: HFP conditions and fuel cycle 1 simulations

Leppänen, J. & Mattila, R., 2016, In : Annals of Nuclear Energy. 96, p. 324-331

Research output: Contribution to journalArticleScientificpeer-review

Monte Carlo methods
Simulators
Specifications
2015
51 Citations (Scopus)

A collision history-based approach to sensitivity/perturbation calculations in the continuous energy Monte Carlo code SERPENT

Aufiero, M., Bidaud, A., Hursin, M., Leppänen, J., Palmiotti, G., Pelloni, S. & Rubiolo, P., 2015, In : Annals of Nuclear Energy. 85, p. 245-258

Research output: Contribution to journalArticleScientificpeer-review

Kinetic parameters
Reaction rates
Scattering

Analyzing the statistics of group constants generated by Serpent 2 Monte Carlo code

Kaltiaisenaho, T. & Leppänen, J., 2015, Proceedings of the International Conference on the Physics of Reactors: PHYSOR 2014. Vol. JAEA-Conf 2014-003. 9 p. 1106126

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Open Access
5 Citations (Scopus)

CAD-based geometry type in serpent 2-application in fusion neutronics

Leppänen, J., 2015, Mathematics and Computations, Supercomputing in Nuclear Applications and Monte Carlo International Conference . Curran Associates Inc., p. 1635-1646

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Computer aided design
Fusion reactions
Geometry
Fusion reactors
Demonstrations

Development of an unstructured mesh based geometry model in the Serpent 2 Monte Carlo code

Leppänen, J. & Aufiero, M., 2015, Proceedings of the international conference on physics of reactors: PHYSOR2014. Vol. JAEA-Conf 2014-003. p. 10 1101586

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Open Access
1 Citation (Scopus)

Effect of the Target Motion Sampling temperature treatment method on the statistics and performance

Viitanen, T. & Leppänen, J., 2015, In : Annals of Nuclear Energy. 82, p. 217-225

Research output: Contribution to journalArticleScientificpeer-review

Statistics
Sampling
Reaction rates
Temperature
Program processors
8 Citations (Scopus)

Modeling of realistic pebble bed reactor geometries using the Serpent Monte Carlo code

Rintala, V., Suikkanen, H., Leppänen, J. & Kyrki-Rajamäki, R., 2015, In : Annals of Nuclear Energy. 77, p. 223-230

Research output: Contribution to journalArticleScientificpeer-review

Pebble bed reactors
Geometry
Finite difference method
Neutrons
High temperature reactors
6 Citations (Scopus)

Module for thermomechanical modeling of LWR fuel in multiphysics simulations

Ikonen, T., Loukusa, H., Syrjälahti, E., Valtavirta, V., Leppänen, J. & Tulkki, V., 2015, In : Annals of Nuclear Energy. 84, p. 111-121

Research output: Contribution to journalArticleScientificpeer-review

Hydraulics
Steam piping systems
Coolants
Heat flux
Temperature distribution