Method for scaling reactor absolute power by fission detection sheet

Abstract

The invention discloses a method for scaling reactor absolute power by fission detection sheets, and the method comprises the following steps: irradiating packaged fission detection sheets with known enrichment in a reactor core for a period of T, after the irradiation, cooling the fission detection sheets for a period of Tw, after cooling, measuring a count C under a photoelectric peak of gamma ray with energy of 293 KeV emitted by a fission product 143 Ce by a high-purity germanium gamma spectrometer, wherein the measuring time is Tm, and finally calculating the absolute nuclear power of the whole reactor. The method of the invention is a new method for scaling reactor absolute nuclear power; with the method, absolute nuclear power of a reactor can be scaled under low power for either a thermal reactor or a fast reactor; and the problem of complicated data processing process for current measuring methods is solved.

Description

technical field [0001] The invention relates to a method for calibrating the absolute power of a nuclear reactor, in particular to a method for calibrating the absolute power of a nuclear reactor using a fission detection chip. Background technique [0002] Absolute power calibration is a work that must be done before the reactor is put into operation. However, in the low power stage, due to the small temperature difference between the inlet and outlet of the core, it is not suitable to use thermal engineering to calibrate the power. At this time, the reactor power can only be calibrated by measuring the fission rate. [0003] The absolute measurement of neutron flux is generally used to determine the fission rate of the reactor, because 235 The energy of one fission of the U nucleus is known, and the power of the entire reactor is easy to determine: [0004] P = E f Σ ‾ ...

AI Technical Summary

Problems solved by technology

[0023] Although the absolute power of the reactor can be calculated more conveniently through this formula, the influence caused by the self-shielding factor of the fission detection piece is not considered in the calculation formula of this formula, and the accuracy of the measurement result is not enough

In addition, in this formula are used separately 235 Correction factor for uneven fission rate and 238 Correction factor for uneven fission rate The fission inhomogeneity of the whole core is not comprehensively considered, and the two correction factors calculated separately by calculation cannot fully represent the inhomogeneity of the core fission rate, and the calculation results will introduce certain errors

In an actual reactor, the fission caused by 238U in the core conversion zone will also affect the measurement of absolute power, and this factor is not considered in the calculation formula

Therefore, the above formula does not guarantee the accuracy of the calculation

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