METHOD FOR DETERMINING HEAT FLOW AND TEMPERATURE FIELDS IN NUCLEAR REACTOR FUEL ASSEMBLY Russian patent published in 1999 - IPC

FIELD: nuclear power engineering. SUBSTANCE: in calculating heat flow fields, specified values of temperature response are found. Then energy release density distribution similar to real one is created in actual fuel element, fuel element surface is isolated everywhere except for some small portion where heat sink is provided, and position of this heat sink is varied each time measuring surface temperature of fuel element. Then experimental model of fuel assembly is made of fuel element simulators whose internal heat conductance is much lower than that of coolant; after that, constant heat flow between coolant and surfaces of simulators is provided at coolant flowrates and temperatures approaching operating conditions of real fuel assembly and temperatures of simulator cans as well as local heat conductivities are found for all possible positions of simulator and throughout its entire length. Then relevant sets of equations are solved for each layer of fuel assembly (for each channel and for each fuel element) to find actual heat flow fields. EFFECT: improved accuracy of temperature measurements. 2 dwg