Investigation of the Hydrodynamic Structure of Throttled Fluid Flow

Improvement of Coolant Flow Controllers

“…The intensification of throttling in flow controllers was validated, including by means of visualization [6][7][8][9]. As the power and coolant pressure increase (to 8 MPa in VVER, 13 MPa in BN-1200, and 20 MPa in BREST), it becomes necessary to develop highly reliable flow controllers with a wide regulation range, long service life and linear and stable flow characteristics.…”

“…The following were studied in the experimental part of this work: 1) hydrodynamic structures of throttled flow (stream flows, stagnant zone, depending on the geometric forms) [9]; 2) rotating and detached vortices with a small opening; 3) effect of the shape and arrangement of the flow section on the formation and expansion of streams at a small opening; 4) effect of the geometric parameters, Reynolds number and the cavitation numbers on the hydraulic resistance coefficient of compact throttles; and 5) effect of throttling intensification methods on the vibration characteristics. The compression of a stream is ε = 0.58-0.65 for a centered opening and ε = 0.67-0.7 for an opening at a wall [9].…”

“…The compression of a stream is ε = 0.58-0.65 for a centered opening and ε = 0.67-0.7 for an opening at a wall [9]. If the tabulated hydraulic resistance coefficients are ζ = 2.5-2.8 with large narrowing are referred not to a narrow geometric section but rather to the narrowest section of the stream, then they become 1-1.2, i.e., for flow through a smooth opening the pressure of the medium decreases only by the size of the dynamic head of the stream ρw 2 /2.…”