ON DEVELOPMENT OF HEAT PIPES FOR NUCLEAR POWER PLANTS

The article discusses the designs of two nuclear reactors cooled by heat pipes with liquid metal coolants. Both designs were developed at IPPE JSC. The first design is a research reactor with a capacity of 1.2 MW. Evaporating sodium is used as a coolant in the core. The evaporating eutectic sodium-potassium alloy is used as a coolant in the secondary loop. The third loop contains gas as working fluid of the Stirling or Brighton cycle. The report presents the results of thermo-hydraulic experiments that confirmed the main design parameters. The second design called RIFMA is an innovative super small NPP with direct conversion of thermal energy into electricity and is supposed, in particular, to be used in the Arctic region. Thermal power is 100 kW, efficiency is not less than 10 %. Molybdenum heat pipes filled with lithium are used to transfer heat from the core. To convert energy, thermophotovoltaic converters are proposed. They are cooled by low-temperature heat pipes that remove residual heat and transfer it to air radiators. A nuclear power plant concept and three versions of the core are presented.