矩形微槽蒸发薄液膜新边界条件的设定  

New Boundary Settings of the Evaporating Thin Film in a Rectangular Groove

作　　者：杜世元[1] 赵耀华[1] 

机构地区：[1]北京工业大学建筑工程学院,北京100124

出　　处：《工程热物理学报》2011年第7期1203-1207,共5页Journal of Engineering Thermophysics

基　　金：北京工业大学人才强教深化计划-创新人才项目-赵耀华(No.00400054R4001)

摘　　要：采用了一种新的边界条件来求解微槽内蒸发薄液膜的控制方程。这种新的边界条件保证在毛细微槽中,本征弯液面区域的液面弯曲中心位于微槽的中心线上,从而消除了传统微槽薄液膜计算模型中产生的物理矛盾。计算结果显示随着过热度的增加,本征弯液面部分的曲率半径不是恒定的,而是逐渐增加的,这导致了本征区域毛细吸力的降低。计算结果同时表明在本征区域的较薄位置,存在一个狭窄的热流密度相当大的子区域。在数值研究中,如果将此子区域用恒定半径的区域来替代,从理论上来讲是不合理的。New boundary settings are developed for the evaporating thin film governing equation. The new settings emphasize the center of the intrinsic meniscus be on the axis of the micro channel. These settings eliminate the physical conflicts caused by the classical evaporating thin film models. The calculation results indicate that the intrinsic meniscus radius is not kept unchanged during evaporating process.Instead,it increases with the superheat of the substrate,which means a reduction of the capillary suction.It is also found at the thinner end of the intrinsic region,a narrow but high heat flux sub-region exists.In numerical study substitute this sub-region with a constant radius region will cause theoretical mismatch.

关 键 词：边界条件 蒸发薄液膜 本征区域半径 

分 类 号：TK124[动力工程及工程热物理—工程热物理]