Foto: Programm Nukleare Entsorgung und Sicherheit ©Copyright: BengsSafety Research for Nuclear Reactors

Energy > Nuclear Waste Management and Safety as well as Radiation Research - All Topics

Foto: Flows in a nuclear reactor ©Copyright: HZDR/Oliver KilligAlthough Germany decided to shut down all nuclear reactors for energy production until 2022, own reactor safety research is needed in future. The preservation of competence in nuclear engineering is essential for the safety assessment of nuclear power plants and nuclear projects in Germany and abroad. Only in that way Germany is able to influence international safety standards and to participate in international research projects.

Based on this background the work within the topic “Reactor Safety” is concentrated on the research on safety aspects of currently operating nuclear reactors and new reactor types being under development in the neighboring countries. It covers the development of methods for analyses of transients and postulated accidents, the investigation of ageing phenomena in materials and integrity of components, and the safety related aspects connected with the thermal fluid dynamics of cooling water or liquid metal flows. Especially after the Fukushima accident in 2011, the efforts on the investigation of accident management measures in nuclear reactors have been increased.


  • Development and validation of neutron kinetic and thermal hydraulic methods for the analysis of design basis and severe accidents for nuclear reactors.
  • Development and qualification of predictive Computational Fluid Dynamics (CFD) models for two-phase flows
  • Conduction of industry-grade experiments for code validation using innovative measuring techniques (TOPFLOW facility)
  • Exploration of the mechanisms of irradiation effects in reactor pressure vessel steels and Gen-IV candidate materials by means of nanostructural characterization, atomistic modelling and mechanical testing

Press Releases

Involved HZDR institutes




  • Davies, S.; Rohde, U.; Litskevich, D. et al.
    CTF and FLOCAL Thermal Hydraulics Validations and Verifications within a Multiscale and Multiphysics Software Development
    Energies 14(2021), 1220 (10.3390/en14051220)
  • Rzehak, R.; Liao, Y.; Meller, R. et al.
    Radial pressure forces in Euler-Euler simulations of turbulent bubbly pipe flows
    Nuclear Engineering and Design 374(2021), 111079 (10.1016/j.nucengdes.2021.111079)
  • Hieckmann, E.; Mühle, U.; Chekhonin, P. et al.
    Investigations of internal stresses in high-voltage devices with deep trenches
    Journal of Vacuum Science & Technology B 38(2020), 064004 (10.1116/6.0000515)
  • Prasser, H.-M.; Hampel, U.; Schütz, P.
    TOPFLOW Pressure Chamber – versatile techniques to simplify design and instrumentation of thermal fluid dynamic experiments at high pressure
    Nuclear Engineering and Design 372(2021), 110971 (10.1016/j.nucengdes.2020.110971)
  • Colombo, M.; Rzehak, R.; Fairweather, M. et al.
    Benchmarking of computational fluid dynamic models for bubbly flows
    Nuclear Engineering and Design 375(2021), 111075 (10.1016/j.nucengdes.2021.111075)
  • Di Nora, V. A.; Fridman, E.; Nikitin, E. et al.
    Optimization of multi-group energy structures for diffusion analyses of sodium-cooled fast reactors assisted by simulated annealing – Part I: methodology demonstration
    Annals of Nuclear Energy 155(2021), 108183 (10.1016/j.anucene.2021.108183)
  • Sprinzl, D.; Krysl, V.; Mikolas, P. et al.
    "Full-Core" VVER-1000 calculation benchmark
    Kerntechnik 85(2020)4, 231-244 (10.3139/124.200023)
  • Meza, A.; Macía, E.; García-Junceda, A. et al.
    Development of New 14 Cr ODS Steels by Using New Oxides Formers and B as an Inhibitor of the Grain Growth
    Metals 10(2020)10, 1344 (10.3390/met10101344)
  • Shah, V.; van Dommelen, J. A. W.; Altstadt, E. et al.
    Brittle-ductile transition temperature of recrystallized tungsten following exposure to fusion relevant cyclic high heat load
    Journal of Nuclear Materials 541(2020), 152416 (10.1016/j.jnucmat.2020.152416)
  • Wasserbäch, W.; Skrotzki, W.; Chekhonin, P.
    Strengthening of ods silver wires
    Materialia 12(2020), 100818 (10.1016/j.mtla.2020.100818)
  • Konstantinovic, M. J.; Ulbricht, A.; Brodziansky, T. et al.
    Vacancy-solute clustering in Fe-Cr alloys after neutron irradiation
    Journal of Nuclear Materials 540(2020), 152341 (10.1016/j.jnucmat.2020.152341)
  • Altstadt, E.; Bergner, F.; Houska, M.
    Use of the small punch test for the estimation of ductile-to-brittle transition temperature shift of irradiated steels
    Nuclear Materials and Energy 26(2021), 100918 (10.1016/j.nme.2021.100918)
  • Kästner, W.; Alt, S.; Seeliger, A. et al.
    Modelling thermal-hydraulic effects of zinc borate deposits in the PWR core after LOCA - Experimental strategies and test facilities
    atw - International Journal for Nuclear Power 65(2020)6/7, 341-345
  • Vivas, J.; De-Castro, D.; Altstadt, E. et al.
    Design and high temperature behavior of novel heat resistant steels strengthened by high density of stable nanoprecipitates
    Materials Science and Engineering A 739(2020), 139799 (10.1016/j.msea.2020.139799)
  • Das, A.; Chekhonin, P.; Altstadt, E. et al.
    Microstructure and fracture toughness characterization of three 9Cr ODS EUROFER steels with different thermo-mechanical treatments
    Journal of Nuclear Materials 542(2020), 152464 (10.1016/j.jnucmat.2020.152464)
  • Fridman, E.; Álvarez-Velarde, F.; Romojaro-Otero, P. et al.
    Neutronic analysis of the European Sodium Fast Reactor: Part II - burnup results
    Journal of Nuclear Engineering and Radiation Science (2021) (10.1115/1.4048765)
  • Fridman, E.; Álvarez-Velarde, F.; Romojaro-Otero, P. et al.
    Neutronic analysis of the European Sodium Fast Reactor: Part I - fresh core results
    Journal of Nuclear Engineering and Radiation Science (2021) (10.1115/1.4048905)
  • Fridman, E.; Huo, X.
    Dynamic simulation of the CEFR control rod drop experiments with the Monte Carlo code Serpent
    Annals of Nuclear Energy 148(2020), 107707 (10.1016/j.anucene.2020.107707)
  • Höhne, T.; Kliem, S.
    Detailed Simulation of the Nominal Flow and Temperature Conditions in a Pre-Konvoi PWR Using Coupled CFD and Neutron Kinetics
    Fluids 5(2020)3, 161 (10.3390/fluids5030161)
  • Hampel, U.; Barthel, F.; Bieberle, A. et al.
    Tomographic imaging of two-phase flow
    International Journal of Advanced Nuclear Reactor Design and Technology 2(2020), 86-92 (10.1016/j.jandt.2020.08.002)
  • Ruiz-Moreno, A.; Hähner, P.; Kurpaska, L. et al.
    Round robin into best practices for the determination of indentation size effects
    Nanomaterials 10(2020)1, 130 (10.3390/nano10010130)
  • Tas-Köhler, S.; Lecrivain, G.; Krepper, E. et al.
    Numerical investigation on the effect of transversal fluid field deformation on heat transfer in a rod bundle with mixing vanes
    Nuclear Engineering and Design 361(2020), 110575 (10.1016/j.nucengdes.2020.110575)
  • Gu, B.; Chekhonin, P.; Schaarschuch, R. et al.
    Microstructure, texture and hardness of a metastable β-titanium alloy after bar-rolling and annealing
    Journal of Alloys and Compounds 825(2020), 154082 (10.1016/j.jallcom.2020.154082)
  • Vogel, K.; Heintze, C.; Chekhonin, P. et al.
    Relationships between depth-resolved primary radiation damage, irradiation-induced nanostructure and nanoindentation response of ion-irradiated Fe-Cr and ODS Fe-Cr alloys
    Nuclear Materials and Energy 24(2020), 100759 (10.1016/j.nme.2020.100759)
  • Neumann-Kipping, M.; Bieberle, A.; Hampel, U.
    Investigations on bubbly two-phase flow in a constricted vertical pipe
    International Journal of Multiphase Flow 130(2020), 103340 (10.1016/j.ijmultiphaseflow.2020.103340)
  • Wagner, M.; Reinicke, S.; Kratzsch, A. et al.
    An analysis for detecting potential relocation of the inventory of dry storage containers during prolonged interim storage via changes in the wall temperature fields
    Nuclear Engineering and Design 366(2020), 110749 (10.1016/j.nucengdes.2020.110749)
  • Bergner, F.; Hernandez-Mayoral, M.; Heintze, C. et al.
    TEM observation of loops decorating dislocations and resulting source hardening of neutron-irradiated Fe-Cr alloys
    Metals 10(2020), 147 (10.3390/met10010147)
  • Höhne, T.
    Simulation of coolant mixing in a BWR spent fuel storage pool and flood chamber
    Nuclear Engineering and Design 359(2020), 110468 (10.1016/j.nucengdes.2019.110468)
  • Diaz Pescador, E.; Grahn, A.; Kliem, S. et al.
    Advanced modelling of complex boron dilution transients in PWRs – Validation of ATHLET 3D-Module against the experiment ROCOM E2.3
    Nuclear Engineering and Design 367(2020), 110776 (10.1016/j.nucengdes.2020.110776)
  • Bilodid, Y.; Fridman, E.; Lötsch, T.
    X2 VVER-1000 benchmark revision: fresh HZP core state and the reference Monte Carlo solution
    Annals of Nuclear Energy 144(2020), 107558 (10.1016/j.anucene.2020.107558)
  • Das, A.; Chekhonin, P.; Altstadt, E. et al.
    Microstructural characterization of inhomogeneity in 9Cr ODS EUROFER steel
    Journal of Nuclear Materials 533(2020), 152083 (10.1016/j.jnucmat.2020.152083)
  • Rydlewicz, W.; Fridman, Emil; Shwageraus, E.
    Modelling ASTRID-Like Sodium-Cooled Fast Reactor with Serpent DYN3D Code Sequence
    European Physical Journal Web of Conferences 247(2021) (10.1051/epjconf/202124702028)
  • Davies, U.; Margulis, M.; Shwageraus, E. et al.
    Evaluation of the ESFR End of Cycle State and Detailed Spatial Distributions of Reactivity Coefficients
    European Physical Journal Web of Conferences 247(2021), 02001 (10.1051/epjconf/202124702001)
  • Garcia, M.; Tuominen, R.; Gommlich, A. et al.
    A SERPENT2-SUBCHANFLOW-TRANSURANUS coupling for pin-by-pin depletion calculations in Light Water Reactors
    Annals of Nuclear Energy 139(2020), 107213 (10.1016/j.anucene.2019.107213)
  • Kozmenkov, Y.; Jobst, M.; Kliem, S. et al.
    The efficiency of sequential accident management measures for a German PWR under prolonged SBO conditions
    Nuclear Engineering and Design 363(2020), 110663 (10.1016/j.nucengdes.2020.110663)
  • Rachamin, R.; Hampel, U.
    Feasibility assessment of using external neutron and gamma radiation measurements for monitoring the state of fuel assemblies in dry storage casks
    Annals of Nuclear Energy 135(2020), 106975 (10.1016/j.anucene.2019.106975)
  • Schäfer, T.; Neumann-Kipping, M.; Bieberle, A. et al.
    Ultrafast X-ray CT imaging for hydrodynamic investigations of gas-liquid two-phase flow in centrifugal pumps
    Journal of Fluids Engineering - Transactions of the ASME 142(2020)4, 041502 (10.1115/1.4045497)
  • Moonesi Shabestary, A.; Bieberle, A.; von der Cron, D. et al.
    Flow morphology and heat transfer analysis for high-pressure steam condensation in an inclined tube part II: Numerical investigations
    Nuclear Engineering and Design 362(2020), 110580 (10.1016/j.nucengdes.2020.110580)
  • Bieberle, A.; Moonesi Shabestary, A.; Geißler, T. et al.
    Flow morphology and heat transfer analysis during high-pressure steam condensation in an inclined tube part I: Experimental investigations
    Nuclear Engineering and Design 361(2020), 110553 (10.1016/j.nucengdes.2020.110553)
  • Manthey, R.; Viereckl, F.; Moonesi Shabestary, A. et al.
    Modeling of passive heat removal systems: A review with reference to the Framatome BWR reactor KERENA : Part II
    Energies 13(2020)1, 109 (10.3390/en13010109)
  • Moonesi Shabestary, A.; Viereckl, F.; Zhang, Y. et al.
    Modelling of passive heat removal systems: A review with reference to the Framatome BWR reactor KERENA :Part I
    Energies 13(2020)1, 35 (10.3390/en13010035)
  • Lucas, D.; Krepper, E.; Liao, Y. et al.
    General guideline for closure model development for gas-liquid flows in the multi-fluid framework
    Nuclear Engineering and Design 357(2020), 110396 (10.1016/j.nucengdes.2019.110396)
  • Unger, S.; Krepper, E.; Beyer, M. et al.
    Numerical optimization of a finned tube bundle heat exchanger arrangement for passive spent fuel pool cooling to ambient air
    Nuclear Engineering and Design 361(2020), 110549 (10.1016/j.nucengdes.2020.110549)
  • Fridman, E.; Valtavirta, V.; Aufiero, M.
    Nuclear Data Sensitivity and Uncertainty Analysis of Critical VENUS-F Cores with the Serpent Monte Carlo Code
    Annals of Nuclear Energy 138(2020), 107196 (10.1016/J.ANUCENE.2019.107196)
  • Castin, N.; Bonny, G.; Bakaev, A. et al.
    The dominating mechanisms for the formation of solute-rich clusters in steels under irradiation
    Materials Today Energy 17(2020), 100472 (10.1016/j.mtener.2020.100472)
  • Höhne, T.; Lucas, D.
    A multiscale approach simulating generic pool boiling
    Nuclear Science and Engineering 194(2020)10, 859-872 (10.1080/00295639.2020.1764265)
  • Konheiser, J.; Mueller, S. E.; Seidl, M.
    Study of the influence of water gaps between fuel assemblies on the activation of an aeroball measurement system (AMS)
    Annals of Nuclear Energy 136(2020), 107005 (10.1016/j.anucene.2019.107005)
  • Sarotto, M.; Firpo, G.; Kochetkov, A. et al.
    Neutronic analyses of the FREYA experiments in support of the ALFRED LFR core design and licensing
    Journal of Nuclear Engineering and Radiation Science 6(2020)1, 011402 (10.1115/1.4044000)
  • Das, A.; Viehrig, H. W.; Bergner, F. et al.
    Effect of microstructural anisotropy on fracture toughness of hot rolled 13Cr ODS steel – the role of primary and secondary cracking
    Journal of Nuclear Materials 491(2017), 83-93 (10.1016/j.jnucmat.2017.04.059)
  • Liao, Y.; Lucas, D.
    Computational modelling of flashing flows: a literature survey
    International Journal of Heat and Mass Transfer 111(2017), 246-265 (10.1016/j.ijheatmasstransfer.2017.03.121)
  • Grahn, A.; Gommlich, A.; Kliem, S. et al.
    Simulation of an MSLB scenario using the 3D neutron kinetic core model Dyn3D coupled with the CFD software Trio U
    Nuclear Engineering and Design 315(2017), 117-127 (10.1016/j.nucengdes.2017.02.002)
  • Höhne, T.; Gasiunas, S.; Šeporaitis, M.
    Numerical Modelling of a Direct Contact Condensation Experiment using the AIAD Framework
    International Journal of Heat and Mass Transfer 111(2017), 211-222 (10.1016/j.ijheatmasstransfer.2017.03.104)