Abstract
In reactor physics tests, it is important to monitor sub-criticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor. This technique is successfully applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected. For operation at low power levels or in the sub-critical domain, the increase in the fluctuation of the neutron signal may cause difficulties in the evaluation of reactivity and the effect of direct emission from the external neutron source may not be neglected. Therefore, contribution of the neutron source must be taken into account and this implies knowledge of a quantity proportional to the source strength, which calls the source term and then it should be determined. The research work has been conducted to measure reactivity with source term using a dedicated reactivity measurement system by the Least Square Inverse Kinetics Method (LSIKM). Application to a simulator of HANARO research reactor, Korea Atomic Energy Research Institute (KAERI), with known source strength and reactivity worth has showed consistent and satisfactory agreement.
Highlights
The inverse kinetics (IK) is widely used for reactivity measurement during nuclear reactor operation
Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor
This technique is successfully applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected
Summary
The inverse kinetics (IK) is widely used for reactivity measurement during nuclear reactor operation. Since reactor is been operated in a steady-state condition, the reactivity can be determined using the point kinetics equations and the source term can be neglected in this case. The first step is to construct the program which is able to calculate the reactivity neglecting source term using the signal from reactor core For this purpose a dedicated on-line reactivity measurement system has been developed that can acquire instantaneous neutron flux signal from reactor instrumentation channel and calculate reactivity. Using this reactivity without source and the signal value, the external source term is to be determined by least square inverse kinetic method. The value of the reactivity determined by the reactivity meter for HANARO research reactor has discussed in the related section
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
