本文阐述国产大型电站直流锅炉采用的φ2×5.5mm碳钢四头内螺纹管和φ18×3mm1 Cr18Ni9Ti不锈钢光管在亚临界及近临界压力区汽水两相流沸腾传热特性的试验研究结果.内螺纹管的试验参数范围为压力P=19.6～22.6MPa、质量流速G=650～1750kg/m~2s,内壁热负荷q=200～610kw/m~2.光管的试验参数范围为P=17.2～22.6MPa,G=800～2000kg/m~2s,q=240～630kW/m~2.通过试验得出了在上述参数范围内的壁温变化特性,确定了发生传热恶化的规律及内螺纹管抑制传热恶化的效果,并对几种结构相近的内螺纹管的传热特性进行了比较和评价. This paper describes the results of experimental studies on the boiling heat transfer characteristics of two-phase flow of soda and flue gas in the subcritical and near-critical pressure zones of the φ2 × 5.5mm carbon steel four-tube female pipe and the φ18 × 3mm1 Cr18Ni9Ti stainless steel light pipe used in the domestic large- The test parameters range of the threaded pipe is P = 19.6 ~ 22.6MPa, mass flow rate G = 650 ~ 1750kg / m ~ 2s, inner wall thermal load q = 200 ~ 610kw / m ~ 2. The experimental parameters of the light pipe are P = 17.2 ~ 22.6MPa, G = 800 ~ 2000kg / m ~ 2s, q = 240 ~ 630kW / m ~ 2. The variation of wall temperature in the range of the above parameters was obtained by experiment and the law of heat transfer deterioration The effect of the thread tube to suppress the deterioration of heat transfer was also compared. The heat transfer characteristics of several internally threaded tubes with similar structures were compared and evaluated.