کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4908868 1427085 2018 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of shape change and initial geometry on water diffusivity estimation during drying of gel model systems
ترجمه فارسی عنوان
اثر تغییر شکل و هندسه اولیه بر برآورد نفوذ آب در طی خشک کردن سیستم های مدل ژل
کلمات کلیدی
سیستم مدل ژل، تجزیه و تحلیل تصویر، فاکتور شکل، نفوذ آب، شبیه سازی،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی


- Drying of cylinder sections and square prisms made from gel was studied.
- Image analysis was used to characterize shrinkage and deformation of samples.
- A new algorithm was used to create a mesh matching the real product shape.
- Shape change and moisture profiles during drying were simulated.
- The effect of geometry and deformation on water diffusivity was appraised.

The mathematical modeling of simultaneous shrinkage and shape change (deformation) during drying of gel model systems (GMS) was investigated. Developed theory was applied to estimate water diffusivities during drying of GMS (70 °C, air velocity of 2 m/s) shaped as square prisms (9.53 mm × 9.53 mm × 80 mm) and longitudinal sections (quarters and halves) of cylinders (12.7 mm diameter × 140 mm length) by considering the product shrinkage with and without deformation. The contours of transversal product slices, obtained from digital images, were averaged to extract relevant characteristics of the dried samples, whereas compactness and roundness were used to evaluate product deformation. Experimental shape patterns were used to estimate the initial and final mesh matching the real product geometry during simulation via a new algorithm. The obtained results demonstrate that although shrinkage occurs from the beginning of drying, changes in product shape are noticeable only after the free moisture fraction is below 0.3. Water diffusivities estimated considering the shape change of product were in the narrow range of 3.37-3.58 × 10−10 m2/s for studied geometries, and are overestimated in about 6-12% when this phenomenon is not included in drying model. No significant differences were observed in water diffusivity values between studied geometries (p > 0.05).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Food Engineering - Volume 216, January 2018, Pages 52-64
نویسندگان
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