EXPERIMENTAL INVESTIGATION OF CAVITATION IN THE CIRCULATION PUMPS WITH LEAD AND LEAD-BISMUTH COOLANTS

摘要

The purpose of this paper is optimization of methods for calculating of flow parts of impeller pumps for high-temperature lead coolant, taking into account specific cavitation performance of the lead coolant [1]. The article presents the studies of cavitation performance of the high-temperature coolant. The studies were conducted in the lead coolant medium at 450 - 550 °C, flow rate up to 25-30 m/s and lead flow pressure from 0 to 5.0 kgf/cm~2 (atm), at oxygen content in lead from 10~(-5)- 10~(-4) up to saturation, as well as in the presence of solid phase of lead oxides in the flow and in the experimental loop with such coolant. With a view to improving the representativeness of the research results, conditions of occurrence and characteristics of gaseous cavitation in the lead coolant flow were determined using three independent methods [2, 3]. The research showed that gas cavitation can take place in lead flows in the vane-type pumps and other components of circulation loops followed by apertures of lead flow discontinuity (bubbles, caverns, etc.), filled up with diluted gas with subsequent disappearance of these apertures of flow discontinuity. Traditional cavitation with formation and subsequent collapse of lead vapors in reactor loops with lead and lead-bismuth coolant is not possible.