关键词: 圆管, 盐析, 流动特性, 多普勒粒子分析仪

Abstract: A phase Doppler particle analyzer was used to measure salt precipitation turbulent flow of sodium carbonate solution under salt precipitation in a round pipe. Experimental results indicate that the relative count density and average diameter of particle phase show a climbing trend with temperature falling. And average diameter of particle phase increases from 40 mm to above 60 mm with the temperature from 30℃ to 15℃. The crystallized particles from salt precipitation are separated out and grow up continually when the supersaturation increases. The fluctuating intensity of liquid phase is lower than that of particle phase at the same temperature and falls down close to the wall surface, but that of particle phase becomes higher. The turbulence is obviously anisotropic during the course of salt precipitation flow. The average velocities of liquid and particle phases are symmetric basically along the horizontal direction at different temperatures. And the average velocity of liquid phase is slightly bigger than that of particle phase, the difference of average velocity between two phases is about 3% of mainstream velocity. Meanwhile, the average velocity of particle phase decreases with the temperature falling down.

Key words: round pipe, salt precipitation, flow features, phase Doppler particle analyzer