关键词: 螺旋管, 流动沸腾, 两相流, 换热系数, 非均匀受热

Abstract: At present,researches on coiled tube,about internal flow and heat transfer characteristics,are only limited under the condition of uniformly heated,at the same time,non-uniform heating are rarely reported. But in practice,spiral tube is heated non-uniformly most of the time. To solve the problem,flow boiling heat transfer characteristics in horizontal helically coiled tube with circumferentially non-uniform heating,under the range of system pressure 0.7—1.0MPa,mass flux 181—364kg/(m²·s) and mass quality 0.07—0.69,were experimentally studied in this paper. The in-tube flow boiling heat transfer coefficient variations with surface heat flux,fluid mass flux,and mass quality were examined under two different non-uniform heating modes and also compared with the data of circumferentially uniform heating condition. Results showed that the in-tube flow boiling heat transfer coefficient was the highest under the condition of the inner half wall heated and outer half wall adiabatic,while it was the lowest with the inner wall heated and outer wall adiabatic.

Key words: helically coiled tube, flow boiling, two-phase flow, heat transfer coefficient, non-uniform heating