摇摆运动对过冷沸腾传热特性影响的机理分析

Mechanism Analysis of Heat Transferring Characteristic in Sub-Cooled Boiling Under Rolling Motion

通过建立静止及摇摆状态下窄矩形通道内的强迫循环过冷沸腾汽泡动力学效应数学模型,分析摇摆状态下过冷沸腾中的滑移汽泡受力行为,讨论摇摆状态下附加惯性力场对汽泡行为影响的规律。基于分相流模型,分析不同摇摆运动参数对过冷沸腾液相流动传热特性及汽泡运动的影响程度,并对理论研究结论进行试验验证。研究结果表明:当摇摆运动不足以导致强迫循环质量流量发生明显变化时,由摇摆运动引入的附加惯性力及由流道空间位置改变引起的浮力变化均不足以改变汽泡运动的规律,因此,摇摆运动对过冷沸腾传热特性的影响可以忽略,获得的结论可为船用换热器性能评价提供参考。

To study the effect of the rolling motion on the sub-cooled boiling heat transferring characteristics in a vertical narrow channel, a bubble dynamic mathematical model is established in this paper, and the effect of the force variation on the sliding bubble under both static and rolling motion conditions is correspondingly investigated. In addition, based on the separation flowing model, the degree to which the rolling motion affects the sub-cooled boiling fluid thermal-hydraulic characteristic and bubble dynamics is studied theoretically and experimentally. The results show that when the mass flux does not pulsate evident- ly with the rolling motion, the additional force induced by the rolling and the variation caused by the buoy- ancy force can not lead to prominent change of bubble motion, either. Therefore, the influence of the rolling motion on the sub-cooled boiling heat transferring characteristic can be treated as negligible, and the obtained results can be treat as reference for ship-based heat exchanger capability evaluation.