煤油在内螺纹管中流动沸腾强化传热特性

针对石油化工过程中沸腾传热设备技术改造的需要 ,在 3× 1 0 5Pa (绝对压力 )的条件下 ,对煤油在垂直内螺纹管中的上升流动沸腾传热进行了实验研究 ,将实验结果同煤油在光管中的实验结果进行了比较 .实验结果表明 ,内螺纹管中的沸腾换热系数是光管的 1 6～ 2倍 ,并且可在小温差条件下实现流动沸腾传热 .提出了煤油在内螺纹管中的流动沸腾换热系数的关联式 ,并对煤油在内螺纹管中的流动沸腾特性和强化传热机理进行了分析 .

CHARACTERISTICS OF ENHANCEMENT OF FLOW BOILING HEAT TRANSFER WITH KEROSENE INSIDE INTERNALLY RIBBED TUBE

To meet the need of modifying the boiling equipment used in petrol chemical industry, flow boiling heat transfer experiments with kerosene in smooth tube and internally ribbed tube are conducted respectively under the condition of 3×10 5 Pa(absolute atmosphere pressure). The experimental results are compared with each other. It shows that the flow boiling heat transfer coefficients in the internally ribbed tube are 1 6—2 times that in the smooth tube and flow boiling heat transfer under the condition of smaller temperature difference can be achieved in the internally ribbed tube. On the basis of the experimental results, a correlation of flow boiling heat transfer coefficient of kerosene in the internally ribbed tube is proposed. Finally the characteristics of flow boiling heat transfer with kerosene and mechanism of enhanced heat transfer in internally ribbed tube are analyzed.