کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
594874 1453991 2011 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Evaporation of sessile drops under combined diffusion and natural convection
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی شیمی کلوئیدی و سطحی
پیش نمایش صفحه اول مقاله
Evaporation of sessile drops under combined diffusion and natural convection
چکیده انگلیسی

Experiments were conducted to investigate the range of applicability of a commonly used assumption for evaporation models of sessile drops, that the transport mechanism that controls the evaporation is vapor diffusion. The evaporation rates of sessile drops of 3-methylpentane, hexane, cyclohexane, and heptane were measured. The radius of the drop contact line was constant during the measurements and drops of radius from 1 mm to 22 mm were studied. It was found that a diffusion-controlled evaporation model underpredicts the evaporation rate from 36% to 80% depending on the drop size. The increase in the evaporation rate was attributed to a second transport mechanism, natural convection of the vapors, and an empirical model was developed for conditions of combined diffusive and convective transport. Over the broad range of volatilities and drop sizes studied, the evaporation rates computed using the combined transport model agree with the measured values with less than 6% root mean square error.

Figure optionsDownload as PowerPoint slideHighlights
► Evaporation rates of sessile hydrocarbon drops were measured.
► The diffusion-controlled evaporation model was investigated.
► Measured rates are faster than diffusion-controlled evaporation.
► The faster evaporation rate is attributed to natural convection.
► An empirical model for combined diffusion and convection was developed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Colloids and Surfaces A: Physicochemical and Engineering Aspects - Volume 381, Issues 1–3, 20 May 2011, Pages 31–36
نویسندگان
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