固体颗粒强化液体沸腾换热和抗垢特性的研究

Investigation on boiling heat transfer enhancement and anti-scaling process by using solid particles

在加热面上添加一定量的固体颗粒 ,可以使沸腾换热强化 .本文在毫米级和纳米级颗粒直径范围内 ,对添加固体颗粒后的液体泡状沸腾换热和抗垢特性进行了系统的实验研究 ,对其强化换热机理进行了理论分析 .实验结果表明 ,沸腾换热强化效果与固体颗粒直径 ,初始颗粒层高度以及沸腾热流密度有关 .流化颗粒具有较好的抗垢作用 .根据“类汽泡运动”所建立的流化颗粒强化沸腾换热的容积对流模型 ,可以较好地反映流化颗粒强化沸腾换热的物理机制 .

Boiling heat transfer can be enhanced by adding solid particles into liquid. An experimental investigation on the effects of solid particles on boiling heat transfer enhancement and scaling process are performed. The size of particles ranges from millimeter to nanometer. The experimental results show that the boiling heat transfer enhancement is closely related to the particle size, the initial bed depth and the heat flux applied. The results also show that the fully fluidized particles can reduce the scaling process on the heating surface. Based on the experimental results the volume convection mechanism of boiling heat transfer enhancement is proposed. The calculated results from the model suggested in this paper agree well with the experimental values.