NPL instruments at the research reactor LVR-15

The research reactor LVR-15 is a medium power light water research reactor operated by the Research Centre Řež. It is a medium power water reactor providing moderate flux of thermal neutrons at nine horizontal radial channes and vertical irradiation channels. NPL uses this facility as a source of neutrons for neutron scattering experiments and nuclear analytical methods. Five neutron scattering instruments are installed at four horizontal thermal neutron channels (HK4 HK6, HK8 and HK9) and serve primarily to resarch in the fields of material science and solid state physics. In addition, one horizontal channel (HK3) hosts special beamline for neutron depth profiling and prompt gamma activation analyses.

Research Reactor LVR - 15

The research reactor LVR-15 at the Research Centre Řež, Ltd. is a light water swimming pool type reactor with force cooling. The maximum reactor power is 10 MW thermal power. Fuel and control elements are of IRT-2M type enriched to 80% or 36% in 235U. Combined water-beryllium reflector is used. The reactor core grid has 80 cells, in the basic operation configuration 28-34 cells contain fuel elements. 2 - 4 of the fuel cells are dedicated to channels for experimental probes and 3 - 6 cells in the reflector and core periphery to vertical irradiation channels. Further 3 cells are dedicated to shut-down rod, 8 cells to compensation rods and 1 cell to fine control rod. The reactor core is situated in the reactor vessel (outer diameter 230 cm, total height of the vessel 623 cm), which is made of steel, the internal parts of the reactor are made of aluminum alloy. The reactor has a forced circulation of the coolant (light demineralised water). The basic operation ON/OFF schedule is 3/1 week.

The reactor serves as a radiation source for:

material testing experiments of the reactor pressure vessel at water loops, where the temperature, pressure, dosis and water chemistry conditions similar to that existing in reactors of nuclear power stations are simulated
material testing at irradiation rigs
activation analysis with the pneumatic rabbit system
experiments at beam tubes in the field of basic and applied research
irradiation of iridium for medical purposes, irradiation for radio-pharmaceutical production
irradiation of silicon single crystals
experiments at the thermal column in the field of neutron capture therapy

Main Reactor Characteristics ^*

Maximum reactor power	10 MW
Maximum thermal neutron flux in the core	1·10¹⁸ n·m^-2·s^-1
Maximum fast neutrons flux in the core	3·10¹⁸ n·m^-2·s^-1
Maximum thermal flux in reflector (mix of Be + H₂O)	5·10¹⁷ n·m^-2·s^-1
*Irradiation facilities*	Thermal neutron flux density (n·cm^-2·s^-1)
Horizontal channels (100/60 mm)	1·10⁸
Maximum thermal neutron flux in the tubes	1·10¹²
Graphite thermal column	1·10¹¹
Irradiation channels	1·10¹⁴in fuel 7·10¹³at core periphery 3-5·10¹³in reflector
Doped silicon facility	1·10¹³
High pressure water loop	5·10¹³