Authors & Affiliations

Delnov V.N.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia

Delnov V.N. – Head of Intellectual Property Department, Dr. Sci. (Tech.), Associate Professor, A.I. Leypunsky Institute for Physics and Power Engineering. Contacts: 1, pl. Bondarenko, Obninsk, Kaluga region, Russia, 249033. Tel.: +7(484) 399-85-68; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

Abstract

The document gives consideration to distributing header systems (DHS). DHS are diverse, complex in their design and constitute a characteristic element of nuclear power unit (NPU) flow parts. The pur-pose of this work is to validate the similarity of flow part hydrodynamics in axially symmetric DHS with various arrangement of liquid inlet into the header. The work also compares the hydrodynamics of flow parts in cylindrical and flat DHS with central liquid inlet and lateral outlet, as well as in cylindrical and flat DHS with lateral liquid inlet and central outlet. A previously unknown hydrodynamics property of the flow parts in axially symmetric DHS with back turn of liquid is identified. It lies in the identity of hydrodynamics of the flow parts in axially symmetric flat and cylindrical DHS in cases of different locations of liquid inlet to the header. This property is based on the presence of jet-eddy flow in the flow parts of above-mentioned DHS, on the generality of liquid properties typical of this type of flow, on the identity of the mechanisms of conversion between jet types, and on the impact of outlet element and header local hydraulic resistance coefficient ratio on the distribution of mass flow rate at the header outlet. This property is induced by expansion of free and semi-submerged jets and, consequently, decrease of average velocity of the fluid in them due to their slowdown, by conversion of submerged jets into semi-submerged ones and vice versa, by the change of maximum velocity location in the jet cross-section on turns and further along the path of the liquid, by movement of some semi-submerged jets along the perforated paths of the outlet elements with flow rate distribution along the path, which are located outside of the meeting point of the jet and outlet element, by the coincidence of locations of maximum liquid flow rate in the jet feeding the outlet element and mass flow rate of the liquid at its outlet, by the direct proportion between average velocity of the jet feeding the outlet element and maximum mass flow rate of the liquid at its outlet, and by the inverse sedate between the maximum mass flow rate of the liquid at the header outlet and the ration between the coefficients of the outlet element and header local hydraulic resistance.

Keywords
hydrodynamics similarity property, flow part, flat and cylindrical distributing header systems, jeteddy flow

Article Text (PDF, in Russian)

References

UDC 621.039.534

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2018, issue 5, 5:22