کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
659018 | 1458099 | 2012 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Temperature dependent viscosity and surface tension effects on deformations of non-isothermal falling liquid film Temperature dependent viscosity and surface tension effects on deformations of non-isothermal falling liquid film](/preview/png/659018.png)
Theoretical and numerical investigations of the heat transfer and hydrodynamics in a liquid film flowing along an inclined substrate under the action of gravity with a local heat source have been performed. A two-dimensional model, based on the thin layer approximation, has been developed describing deformations of the film interface. Equation of a non-isothermal thin-film flow with linear dependence of viscosity and surface tension on temperature is derived. A generalized analytical formula for the film thickness as a function of liquid flow-rate is obtained. Marangoni flow, due to local temperature changes, opposes the gravitationally driven film flow and forms a horizontal bump near the upper edge of the heater. Attention is paid to the viscosity effect on the shape of the bump and the film thinning on the local heaters. A second order deformation of the free surface before the bump up to flow may exist. The criterion for the appearance of this deformation is found analytically.
Journal: International Journal of Heat and Mass Transfer - Volume 55, Issue 4, 31 January 2012, Pages 1271–1278