Development of a research reactor power measurement system using cherenkov radiation

Nuclear research reactors are often found in open pools, allowing visibility of the core and the bluish luminosity of the Cherenkov radiation. In general, the thermal energy released in these reactors is monitored by chambers that measure neutron flux, because this is proportional to the power. There are other methods used to measure the power, including measure of the fuel rod central temperature and the energy balance in the heat exchanger. The brightness of Cherenkov radiation is caused by the emission of visible electromagnetic radiation (in the blue band) by charged particles that pass through an insulating medium (water in nuclear research reactors) at a speed greater than that of light in this medium. This effect was characterized by Pavel Cherenkov, earning him the Nobel Prize in physics in 1958. The objective of the present project is to develop an innovative and alternative method to monitor the power of nuclear research reactors. This will be done by analyzing and monitoring the intensity of luminosity generated by the Cherenkov radiation in the reactor core. This method will be valid for powers up to 250 kW, because above this value the brightness is saturated, as determined by previous studies. The reactor that will be used to test the method is the IPR R1 Triga, located at the Nuclear Technology Development Center (CDTN), currently with a maximum operating power of 250 kW. This project complies with the recommendations of the International Atomic Energy Agency (IAEA) on the safety of reactors. It will provide more redundancy and diversification in this measurement and will not interfere with the operation of the reactor.