Authors & Affiliations

Shlepkin A.S., Morozov A.V., Sakhipgareev A.R., Kalaykin D.S.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia

Shlepkin A.S.– Junior Researcher. Contacts: 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7 (484) 399-81-19; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Morozov A.V. – Leading Researcher, Dr. Sci. (Techn.).
Sakhipgareev A.R. – Junior Researcher.
Kalaykin D.S. – Deputy Head of Laboratory, Cand. Sci. (Techn.).


The article presents the results of experimental studies of the thermophysical (density, viscosity) and physicochemical (degree of acidity – pH) properties of water solutions of boric acid. A review of the available literature data on the effect of the properties of boric acid solutions on heat removal from the reactor core is presented. It has been established that the available information is very general and does not cover the entire range of parameters (temperature, pressure, acid concentration) characteristic of a possible emergency at a nuclear power plant with a VVER reactor. Methods and facilities for conducting experimental studies are described. The results of experimental studies are presented. The density of aqueous solutions of boric acid with a concentration of 2.5–450 g/kg Н2О at a temperature of 25–130 °C was determined. The dependence of the investigated characteristic on temperature and concentration was also obtained. The results of an experimental study of the kinematic viscosity of water solutions of boric acid with a concentration of 2.5–200 g/kg H2O at a temperature of 25–90 °C were obtained. The total error in measuring the viscosity of aqueous solutions of boric acid did not exceed 2 %. The pH values of water solutions of boric acid in the temperature range 25–50 and concentrations of 2.5–450 g/kg H2O were determined. The dependence for calculating the degree of acidity of boric acid is obtained. Experimental data on the thermophysical and physicochemical properties of water solutions of boric acid can be used to refine the results of calculations of emergency heat removal processes in a reactor facility, carried out using both one-dimensional calculation programs and three-dimensional CFD codes.

VVER, passive safety systems, core, boric acid, crystallization, viscosity, dencity, pH

Article Text (PDF, in Russian)


UDC 621.039.524:536.24

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2021, issue 2, 2:18