Authors & Affiliations

Golub E.V., Arnoldov M.N., Kurbatov I.M.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia

Golub E.V. – Researcher, A.I. Leypunsky Institute for Physics and Power Engineering. Contacts: 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7(484) 396-99-47; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Arnoldov M.N. – Chief Researcher, Dr. Sci. (Tech.), A.I. Leypunsky Institute for Physics and Power Engineering.
Kurbatov I.M. – Senior Researcher, Dr. Sci. (Tech.), A.I. Leypunsky Institute for Physics and Power Engineering.

Abstract

Normal NPP operation involves transient dynamic modes (unit start-up, shutdown, power change, loop shutdown, implementation of equipment during unit operation etc.) that make it necessary to control the temperature of core elements in these conditions. Dynamic conditions of the environment impact the error of its temperature measurement. Thermal inertia is a characteristic dynamic property of core element temperature measurement channels.

Similarly to the conventional approach, the complex having time dimension is assumed as the time constant τi of the temperature measurement channel: cTTfT, where: fT - thermal detector heat exchange surface; cT – thermal detector total specific heat; αT – heat transfer coefficient to the thermal detector.

A method of determination of time constants of temperature measurement channels without dismantling is described. The method is based on the temperature signal lag after the power change of reactor unit. An example of method application is given. Additionally, the velocity of coolant in the controlled heat exchange channels is determined. The result accuracy estimation is performed. The presented algorithm of determination of time constants of temperature measurement channels under reactor operating conditions can be useful for temperature control reliability assurance in dynamic modes.

Keywords
reactor core channels, flow area, deviations, coolant velocity, correlation, thermal heat capacity, thermal inertia

Article Text (PDF, in Russian)

References

UDC 621.039.51

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants", 2017, issue 2, 2:13