对高质量流速下立式螺旋管内高压汽液两相流沸腾传热特性进行了试验研究,参数范围为:系统压力8.0-15.0MPa;质量流速2500-4000kg/m^2s;壁面热流密度200-1000kW/m^2;实验段为Ф14×2mm的不锈钢管弯制而成的螺旋管直径比为D/d=30.1的管圈,总长为2.335m,考察了热流密度和质量流速对两相传热的影响,分析核态沸腾和两相强制对流沸腾机理在螺旋管内两相传热中所起的作用,得到了局部传热系数的分布特性和平均传热系数计算关联式,首次发现高质量流速区域内螺旋管内汽液两相传热效果亦趋近于相同条件下直管内的换热系数,并对已有的结论进行了分类比较分析。
Experiments were conducted to further understand the heat transfer in two-phase flow in vertical helically-coiled tubes. The experiments covered a wide range of pressure 8.0-15.0 MPa, mass flow rate 2500-4000 kg/(m^2s), heat flux 200-800 kW/m^2. The experimental segment is 2.335 meter long and made by Ф14×2 mm steel tube .The diameter ratio D/d is 30.1. Through analyzing the influence of heat flux, mass velocity on average heat transfer coefficient, we acknowledge the activities of nucleate boiling and forced convection two mechanism on steam-water two-phase heat transfer in helical coils tubes at high mass flow rate. The average and local heat transfer coefficient correlations were obtained. At high mass flow rate conditions, the effect of heat transfer in the steam-water two- phase flow in helically coils is inclined to that of straight tube at same conditions and the results are compared.