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采用热块骤冷实验技术、非稳态一维数值分析方法和多元回归分析技术对竖直圆形元件管内下降流过渡沸腾传热特性进行了研究，建立了一组以ＣＨＦ点和最小膜态沸腾点（ＭＩＮ）为基础的过渡沸腾传热特性两点模型，和可以反映压力、流量和入口过冷度对过渡沸腾曲线影响的多变量数据分析模型。采用一维非稳态数值分析方法建立热块及试验管的精细温场分布，推导管内壁温度和热流密度，采用本文的模型和多元回归分析技术整理实验数据，得到一组过渡沸腾传热特性的半经验关系式，其适用于：Ｇ＝７０－２２５６ｋｇ／ｍ２·ｓ；Ｐ＝０．３－１６ＭＰａ；ΔＴｓｕｂ＝６℃－７５℃；预测结果与实验数据吻合较好。对主要流动参数对过渡沸腾传热特性的影响作了趋势分析和机理浅析。
In this paper, the heat transfer characteristics of the transitional boiling heat transfer in vertical tube flow were studied by using the thermal block quenching technique, the unsteady one-dimensional numerical analysis method and the multiple regression analysis technique. Boiling point (MIN) -based transient boiling heat transfer characteristics and a multivariate data analysis model that can reflect the effects of pressure, flow and inlet undercooling on the transition boiling curve. The one-dimensional unsteady numerical analysis method was used to establish the fine temperature field distribution of the thermal block and the test tube. The temperature and heat flux of the inner wall of the tube were deduced. The experimental data were obtained by the model and multivariate regression analysis. Of the empirical relationship, which applies to: G = 70-2256kg / m2 · s; P = 0.3-1 6MPa; ΔTsub = 6 ℃ -75 ℃; forecast results and experimental data agree well. The influence of the main flow parameters on the transition boiling heat transfer characteristics was analyzed and the mechanism was analyzed.