نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مکانیک بیوسیستم، دانشکده کشاورزی، دانشگاه شیراز، شیراز، ایران

2 گروه مهندسی مکانیک بیوسیستم دانشگاه جهرم، جهرم، ایران

چکیده

در تحقیق حاضر، تأثیر توان مایکروویو و ضخامت نمونه‌ها بر ضریب­های انتقال جرم ورقه‌های سیب‌زمینی بررسی شده­است. داده‌های تجربی از خشک کردن ورقه‌های سیب‌زمینی با ضخامت‌های 3.5، 5، 7 و 9 میلی‌متر با چهار سطح توان مایکروویو 200، 400، 600 و 800 وات به دست آمد. از مدل تحلیل دینسر و داست برای مدل‌سازی فرآیند خشک کردن و تخمین ضریب­های انتقال جرم در نمونه‌ها استفاده شد. عدد بایوت در محدود 1.299 تا 4.096 به دست آمد و با افزایش توان مایکروویو و کاهش ضخامت نمونه‌ها بهبود یافت. ضریب­های انتشار رطوبت و انتقال جرم سطحی ورقه‌های سیب‌زمینی به ترتیب از 8-10*2.389 تا 8-10*14.681 متر مربع بر ثانیه و از 5-10*2.246 تا 5-10*7.116 متر بر ثانیه متغیر و به‌طور معنی‌داری (در سطح احتمال 5 درصد) با افزایش توان مایکروویو و ضخامت نمونه‌ها افزایش یافتند. انرژی‌های فعال‌سازی انتشار رطوبت و تبخیر رطوبت سطحی به ترتیب در محدوده‌های 1.451-1.746 وات بر گرم و 0.712-1.323 وات بر گرم به دست آمدند.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Modeling the Drying of Potato Slices in a Microwave Dryer and Determining the Mass Transfer Parameters

چکیده [English]

In the present work, the influences of microwave power and samples thickness on the mass transfer parameters of potato slices were studied using the analytical model suggested by Dincer and Dost. Four microwave powers of 200, 400, 600 and 800 W were practiced to dry mono layer of the slices with thicknesses of 3.5, 5, 7 and 9 mm. The Biot number was obtained to be in the range of 1.299–4.096; where decreased following the increment in microwave power and increased with increasing samples thickness. The moisture diffusivity and convective mass transfer coefficient were found to be significantly (P < 0.05) increased with increasing microwave power and the slices thickness, and varied in the ranges of 2.389×10-8–14.681×10-8 m2 s-1 and 2.246×10-5–7.116×10-5 m s-1, respectively. The activation energies for moisture diffusion and surface mass evaporation were determined to be in the ranges of 1.452–1.746 W g-1 and 0.712–1.323 W g-1, respectively.

کلیدواژه‌ها [English]

  • Analytical model
  • Biot number
  • Moisture diffusivity
  • Surface mass transfer
  • Activation energy
Akhondi, E., Kazemi, A. and Maghsoodi, V. 2011. Determination of a suitable thin layer drying curve model for saffron (Crocus sativus L) stigmas in an infrared dryer. Scientia Iranica. 18(6): 1397–1401.
Akpinar, E.K. and Dincer, I. 2005. Moisture transfer models for slabs drying. International Journal of Heat and Mass Transfer. 32(1-2): 80–93.
Amiri Chayjan, R., Kaveh, M. and Khayati, S. 2015. Modeling drying characteristics of hawthorn fruit under microwave-convective conditions. Journal of Food Processing and Preservation. 39(3): 239–253.
Beigi, M. 2016. Influence of drying air parameters on mass transfer characteristics of apple slices. Heat and Mass Transfer. 52(10): 2213–2221.
Beigi, M, 2017. Mass transfer parameters of celeriac slices during vacuum drying. Heat and Mass Transfer. 53(4): 1327–1334.
Dadali, G., Apar, D.K. and Özbek, B. 2007. Microwave drying kinetics of okra. Drying Technology. 25(5): 917–924.
Darvishi, H., Mohammadi, P., Azadbakht, M. and Farhudi, Z. 2018. Effect of different drying conditions on the mass transfer characteristics of kiwi slices. Journal of Agricultural Science and Technology. 20(2): 249–264.
Demiray, E. and Tulek, Y. 2012. Thin-layer drying of tomato (Lycopersicum esculentum Mill. cv. Rio Grande) slices in a convective hot air dryer. Heat and Mass Transfer. 48(5): 841–847.
Dincer, I. and Dost, S. 1995. An analytical model for moisture diffusion in solid objects during drying. Drying Technology. 13(1–2): 425–435.
Dincer, I. and Dost, S. 1996. A modelling study for moisture diffusivities and moisture transfer coefficients in drying of solid objects. International Journal of Energy Research. 20(6): 531–539.
Evin, D. 2011. Microwave drying and moisture diffusivity of white mulberry: experimental and mathematical modelling. Journal of Mechanical Science and Technology. 25: 2711–2718.
Ghanbarian, D., Baraani Dastjerdi, M. and Torki-Harchegani, M. 2016. Mass transfer characteristics of bisporus mushroom (Agaricus bisporus) slices during convective hot air drying. Heat and Mass Transfer. 52(5): 1081–1088.
Jahedi Rad, S., Kaveh, M., Rasooli Sharabiani, V. and Taghinezhad, E. 2018. Fuzzy logic, artificial neural network and mathematical model for prediction of white mulberry drying kinetics. Heat and Mass Transfer. 54(11): 3361–3374.
Kaya, A., Aydın, O. and Dincer, I. 2008. Experimental and numerical investigation of heat and mass transfer during drying of Hayward kiwi fruits (Actinidia Deliciosa Planch). Journal of Food Engineering. 88(3), 323–330.
Kaya, A., Aydin, O. and Dincer, I. 2010. Comparison of experimental data with results of some drying models for regularly shaped products. Heat and Mass Transfer. 46(5): 555–562.
Markowski, M., Bondaruk, J. and Błaszczak, W. 2009. Rehydration behavior of vacuum-microwave-dried potato cubes. Drying Technology. 27:296–305.
McMinn, W.A.M. 2004. Prediction of moisture transfer parameters for microwave drying of lactose powder using Bi-G drying correlation. Journal of Food Engineering. 37(10): 1041–1047.
Mrkić, V., Ukrainczyk, M. and Tripalo, B. 2007. Applicability of moisture transfer Bi-Di correlation for convective drying of broccoli. Journal of Food Engineering. 79(2): 640–646.
Nguyen, M.H. and Price, W.E. 2007. Air-drying of banana: Influence of experimental parameters, slab thickness, banana maturity and harvesting season. Journal of Food Engineering. 79(1): 200–207.
Sadeghi, M., Mirzabeigi Kesbi, O. and Mireei, S.A. 2013. Mass transfer characteristics during convective, microwave and combined microwave-convective drying of lemon slices. Journal of the Science of Food and Agriculture. 93(3): 471–478.
Srikiatden, J. and Roberts, J.S. 2006. Measuring moisture diffusivity of potato and carrot (core and cortex) during convective hot air and isothermal drying. Journal of Food Engineeering 74:143–152.
Süfer, Ö., Sezar, S. and Demir, H. 2017. Thin layer mathematical modeling of convective, vacuum and microwave drying of intact and brined onion slices. Journal of Food processing and Preservation. 41(6): https://doi.org/10.1111/jfpp.13239
Tiwari, A. 2016. A review on solar drying of agricultural produce. Journal of Food Processing and Technology. 7(9): 1–12.
Torki-Harchegani, M., Ghanbarian, D., Ghasemi-Pibalouti, A. and Sadeghi, M. 2016. Dehydration behaviour, mathematical modelling, energy efficiency and essential oil yield of peppermint leaves undergoing microwave and hot air treatments. Renewable and Sustainable Energy Reviews. 58: 407–418.
Torki-Harchegani, M., Ghanbarian, D. and Sadeghi, M. 2015. Estimation of whole lemon mass transfer parameters during hot air drying using different modelling methods. Heat and Mass Transfer. 51(8): 1121–1129.
Wang, J. and Xi, Y.S. 2005. Drying characteristics and drying quality of carrot using a two-stage microwave process. Journal of Food Engineering. 68(4): 505–511.
Yao, Y., Zhang, W., Yang, K., Liu, S. and He, B. 2012. Theoretical model on the heat and mass transfer in silica gel packed beds during the regeneration assisted by high-intensity ultrasound. International Journal of Heat and Mass Transfer. 55(23–24): 7133–7143.