Visualization and prediction model on shape of liquid bridge

doi:10.11949/j.issn.0438-1157.20151707

Abstract

Abstract:

Water bridge can affect the performance of fin-and-tube heat exchanger working under dehumidifying. In order to know the influence of water bridge on heat exchanger, the shape of water bridge needs to be studied. In this research, a visual experiment was used to develop the prediction model of water bridge shape. Based on the visual experiment, the contact line and the contact angles of water bridge were measured, covering various water volumes, solid plate separations and five different solid materials. The prediction model of contact line via correlated aspect ratio was developed, and the prediction model of contact angles via the correlated maximum and minimum contact angles was proposed. The mean deviation of aspect ratio of contact line was 3.4% and that of contact angles was 7.9%.

Key words: water bridge shape, contact angle, prediction, model, experimental validation

摘要：

了解析湿工况下液桥对管翅式换热器性能的影响,需要对液桥形状进行实验研究并建立描述液桥形状的方法。通过搭建可视化实验台观察了液桥在竖直平板间的形状,并测量了液桥的接触线和接触角。实验研究了不同体积、不同平板间距、不同平板材料间形成的液桥,并通过实验数据开发了能够描述液桥形状的关联式,包括接触线伸长比和接触角分别与Bond数的关联式。还根据关联式建立了描述液桥形状的方法并将结果与实验数据进行对比,对比结果显示接触线的描述方法平均误差为3.4%,接触角的描述方法平均误差为7.9%。

关键词: 液桥形状, 接触角, 预测, 模型, 实验验证

CLC Number:

TK124

ZHUANG Dawei, YANG Yifei, HU Haitao, DING Guoliang. Visualization and prediction model on shape of liquid bridge[J]. CIESC Journal, 2016, 67(6): 2224-2229.

庄大伟, 杨艺菲, 胡海涛, 丁国良. 竖直平板间液桥形状的观测与预测模型开发[J]. 化工学报, 2016, 67(6): 2224-2229.

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