Research Reactor LVR-15

History

LVR-15 hall

The first research reactor in the Czech lands started its operation in 1957 in the Institute of Nuclear Physics (Czechoslovak Academy of Sciences) in Rez near Prague. The reactor’s thermal power was 2 MW. This reactor was in operation until 1987 and then during 1988 – 1989 the reactor underwent  reconstruction from a VVR-S to an LVR-15 type. The reconstruction project was prepared at the beginning of the 1980s and the goal was a power uprate and an increase in safety. Test operations of the LVR-15 reactor commenced in 1989, and the reactor has been operating on full power since 1995.

Reactor Description

LVR-15 scheme

LVR-15 is a light water tank-type research reactor placed in a stainless steel vessel under a shielding cover. It has forced cooling, IRT-4M fuel and an operational power level of 10 MWt. Reactor operations run in campaigns. Usually the campaign lasts for 3 weeks, followed by an outage lasting for 10-14 days  for maintenance and fuel reloading. There are also other campaigns which can operate for ‘short-time’ experiments. As a moderator and an absorber, demineralised water is used. A reflector is composed of a water, or beryllium block, depending on the operation configuration.

Technical Parameters

Reactor Vessel

Operation Parameters

Fuel

Power control

Reactor Utilization

The research reactor LVR-15 is used for research and production in cases of:

• Material research (e.g. an irradiation of reactor pressure vessel (RPV) materials)
• Corrosion tests of primary circuit and internal structural materials of nuclear power plants) in experimental loops and probes
• Water chemistry experiments for nuclear power plant primary circuits
• Neutron activation analysis (used to determine materials composition)
• Development and production of new radiopharmaceuticals (¹⁵³Sm, ¹⁶¹Tb, ¹⁶⁵Dy, ¹⁶⁶Hop, ¹⁶⁹Er, ⁶⁰Co, ¹⁹²Ir, ¹⁸²Ta, ¹⁹⁸Au)
• Production of silicon through neutron doping for the electronic industry (the phosphorus doping of silicon utilizing neutron irradiation significantly improves specific resistance homogeneity compared to other methods)
• Irradiation services (production of radioisotopes: ⁹⁹Mo-⁹⁹mTc, ¹¹³Sn-¹¹³mIn, ¹⁸⁸W-¹⁸⁸Re)
• Scientific research into horizontal channel material characteristics (neutron physics and solid phase physics)
• Neutron capture therapy (irradiation of patients with glioblastoma-type brain tumours)

Neutron beams exiting the reactor via horizontal channels are used by scientific staff of the Nuclear Physics Institute of the Academy of Sciences of the Czech Republic and the Faculty of Nuclear Sciences and Physical Engineering of the Czech Technical University in Prague for the following experiments:

• Neutron measurement of structures and textures at room and helium temperatures
• Deep neutron profiling and th study of immediate gamma radiation from neutron radiation capture
• Neutron optics and neutron topography
• Measuring textures in semi-crystalline metal materials.
• Study of structural inhomogeneities using the diffraction and the small-angle neutron scattering methods
• Neutron interferometry
• Study of local tension in polycrystalline materials

Irradiation Services at LVR-15 Reactor and Epithermal Neutron Beam

Irradiation services at LVR-15 reactor and epithermal neutron beam provide:

• Proposal of an irradiation workstation involving neutron source, neutron moderation and filtering; geometric arrangement of the volume under specific conditions and shielding by calculating the transport of neutrons and photons
• Irradiation of material samples by the epithermal neutron beam (flux density 7×108 n.cm^-2.s^-1) in terms of experimentally verified conditions with the possibility of heating the samples up to 300 °C
• Sample irradiation in vertical irradiation channels
• Fission neutron irradiation of samples in vertical irradiation channels located in the beryllium and water displacers
• Production of neutron doped silicon – silicon single crystal irradiation facility in “DONA” device
• Handling and technological operations with ionizing radiation sources in hot cells
• Transhipment of ionizing radiation sources from one cask to another
• Visual control of ionizing radiation sources
• Dose rate measurements at a defined distance from the ionizing radiation sources
• Other manipulations with ionizing radiation sources according to specific customer requirements

Material Irradiation Research and Services

Material irradiation research and services provide:

• Irradiation experiments focused on material behaviour research and influence of radiation and chemical parameters
• Study of structural materials’ behaviour in the aquatic environment under chemical parameters and radiation conditions
• Studies on the compatibility and corrosion behaviour of structural materials in various environments (helium, liquid metals and molten salts)
• Experiments in the experimental facilities of the research reactor LVR-15, including continuous monitoring of experimental conditions (thermohydraulic, chemical and radiological)
• Evaluation of corrosion behaviour of structural materials in steam circuits and liquid metals
• Evaluation of local and surface damage mechanism and the nature of corrosion attack in operational conditions
• Assessment of corrosion damage mechanism under model operational conditions, depending on the level of mechanical stress and composition of the aquatic environment
• Evaluation of corrosion behaviour of fuel cladding materials, including eddy current measurement