ABSTRACT

Heat transfer experiment on water flow boiling was carried out in the upward direction under atmospheric pressure through a narrow rectangular channel heated on one-side by vapor having a gap of 2.75 mm, a width of 250 mm, and length of 1400 mm. The heat transfer coefficient and thermal hydraulic thresholds of the flow boiling in forced convective flow, such as the onset of nucleate boiling (ONB) and onset of fully developed nucleate boiling (OFDB) were investigated. The experiment was performed over a wide range of inlet temperature (75–95°C), mass flow rate (2–9 g/m), and heat fluxes (5–16 kW/m²). The effects of the parameters on the heat transfer coefficients have been discussed in detail. A series of ONB, FDB and heat transfer correlations were evaluated using the experimental data, and most of the correlations did not adequately fit the experimental results. A modified Hong et al. correlation and modified Zhu et al. correlation were used to predict the wall superheat at ONB and FDB respectively. The average errors (AEs) of the two correlations were 2.36% and −0.68%, and the root mean square errors (RMSEs) of them were both 14.00%. A modified Li and Wu correlation was used to predict heat transfer coefficients with the average error (AE) of 1.46% and the root mean square errors (RMSE) of 11.88%.

摘要

水流沸腾传热实验是在大气压下通过一侧被蒸汽加热的狭窄矩形通道进行，该通道的间隙为2.75mm，宽度为250mm，长度为1400mm。研究了强制对流流动中流动沸腾的传热系数和热水力阈值，例如核态沸腾的开始（ONB）和完全发展的核态沸腾的开始（OFDB）。该实验在较宽的入口温度 (75–95°C)、质量流量 (2–9 g/m) 和热通量 (5–16 kW/m ²）。详细讨论了参数对传热系数的影响。利用实验数据评估了一系列ONB、FDB和传热相关式，大多数相关式与实验结果不充分吻合。修改后的 Hong 等人。相关性和修改朱等人。相关性分别用于预测 ONB 和 FDB 处的壁过热度。两个相关性的平均误差（AE）分别为2.36%和-0.68%，均方根误差（RMSE）均为14.00%。使用修正的 Li 和 Wu 相关性来预测传热系数，平均误差 (AE) 为 1.46%，均方根误差 (RMSE) 为 11.88%。