Enhancement of Heat and Mass Transfer through Falling Liquid Film by Surface Wave Control

表面波控制通过下降液膜增强传热传质

• 批准号: 13650232
• 负责人: MIYARA Akio
• 金额: $ 2.3万
• 依托单位: Saga University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650232/
• 关键词: Wavy falling film; Absorption; Numerical simulation; LiBr aqueous solution; Heat and mass transfer; Enhancement mechanism; 臭化リチウム水溶液; 表面波; 水蒸気吸収; 熱伝達; 物質伝達; ガス吸収

From experimental measurement of oxygen absorption into falling water film imposed periodic disturbances, it has been clarified that an optimum wave exists for absorption enhancement. Numerical simulations have been carried out for wave evolution on falling liquid film and for steam absorption by wavy falling film of LiBr aqueous solution, where developments of the waves, absorption at the interface, and heat and mass transfer in the film are solved simultaneously. Small disturbance waves given at the inflow boundary, grow into developed waves. Wave evolution is classified into three categories, according to wave frequency. Streamlines, concentration and temperature fields in the wavy film are shown. Recirculation which appears in a large wave involves low, concentration solution near the interface and discharges it at the wave rear. Absorption rate is very high in the area of capillary waves accompanies with the large wave and it is minute in the region between the front and crest of the large wave. Velocity field around wave trough in front of large wave becomes complicated and back flow is generated.

通过对周期性扰动下降水膜吸氧量的实验测量，阐明了降水膜吸氧量存在一个最佳吸收波。对溴化锂水溶液下降液膜上的波动演化和波状下降膜吸收水蒸气的过程进行了数值模拟，同时求解了波动的发展、界面的吸收和膜内的传热传质。在入流边界处产生的小扰动波发展成为发展波。根据波的频率，波的演变分为三类。给出了波纹膜中的流线、浓度场和温度场。在大浪中出现的再循环，涉及界面附近的低浓度溶液，并在浪后排出。在伴随大浪的毛细波区域，吸收率很高，而在大浪的前沿和波峰之间的区域，吸收率很小。大浪前波谷附近的速度场变得复杂，并产生回流。

项目成果

T.Nosoko, A.Miyara: "The evolution and subsequent dynamics of waves on a vertically falling liquid film"Physics of Fluids. 16-4. 1118-1126 (2004)

T.Nosoko、A.Miyara：“垂直下落液膜上波的演化和随后的动力学”流体物理学。

宮良明男: "鉛直面を流下するLiBr水溶液による水蒸気吸収の数値シミュレーション"第40回日本伝熱シンポジウム講演論文集. 2003年5月(発売予定).

Akio Miyara：“LiBr 水​​溶液沿垂直面流动的水蒸气吸收的数值模拟”第 40 届日本传热研讨会论文集，2003 年 5 月（计划发布）。

A.Miyara: "Numerical Simulation of Heat and Mass Transfer of Wavy Falling Films"2nd International Berlin Workshop on Transport Phenomena with Moving Boundaries. (2003)

A.Miyara：“波状下落薄膜传热传质的数值模拟”第二届柏林移动边界传输现象国际研讨会。

Akio Miyara, Tomoki Yamamoto, Toru Iemura, Takashi Shimada: "Gass absorption by wavy falling liquid film formed on inner surface of vertical tubes"Proc. 6th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows. 46

Akio Miyara、Tomoki Yamamoto、Toru Iemura、Takashi Shimada：“垂直管内表面形成的波状下降液膜的气体吸收”Proc。

宮良 明男: "鉛直面を流下するLiBr水溶液による水蒸気吸収の数値シミュレーション"第40回日本電熱シンポジウム講演論文集. 1. 341-342 (2003)

Akio Miyara：“垂直平面下流动的溴化锂水溶液吸收水蒸气的数值模拟”第 40 届日本电热研讨会论文集 1. 341-342 (2003)。