汽-气层流凝结气液膜内物理量分布的研究

Research on Distributions of Physical Quantities in the Gas-Liquid Films of Vapor-gas Laminar Condensation

在汽-气凝结过程中,不凝结气的存在使凝结换热恶化,影响换热效率。为深入认识其影响机理和为强化汽-气凝结换热提供指导,建立了水平管外汽-气层流凝结气膜内不凝结气浓度、温度和速度及液膜内温度、速度分布的数学模型。以水蒸汽-空气为例,计算得到了气膜内不凝结气浓度、温度和速度及液膜内温度、速度的分布规律。

Non-condensable gases make condensation heat transfer deteriorate and affect heat transfer efficiency in the vapor-gas condensation heat transfer processes. In order to guide to enhance vapor-gas condensation heat transfer, this investigation established a mathematical model of non-condensable gas concentration, temperature and velocity in the gas film and temperature and velocity in the liquid film about vapor-gas laminar condensation outside a horizontal tube. Take steam-air mixture as an example, one obtained distributions of non-condensable gas concen- tration, temperature and velocity in the gas film and temperature and velocity in the liquid film.