Drying mathematical modeling and the effect of different atmospheric conditions on the efficiency of the hybrid-solar dryer

Document Type : Original Article

Authors

1 Department of Mechanical Engineering of Biosystems, Razi University, Kermanshah, Iran

2 Young Researchers and Elite Club, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran

3 Department of Mechanical Enginnering of Biosystems, Razi University, Kermanshah, Iran

Abstract

This paper presents the thin layer drying behavior of Dill by a solar hybrid dryer. Experiments were carried out at the air temperatures of 40ºC, 50ºC, 60ºC, 70ºC and air velocity of 1m/s, 1.5 and 2 m/s. 5 different thin layer drying models were fitted to experimental data. The high values of coefficient of determination and the low values of reduced chi-square and root mean square error indicated that the Aghbashlo et al. model could satisfactorily describe the drying curve of Dill. According to resultsThe drying rate increased with an increase in the drying air temperature and drying air velocity. Also the effect of the air velocity on the drying time at a low temperature is greater than that at a high temperature. Based on the results, the mean values of increasing in air temperatures by solar radiation for cloudy, partly cloudy and sunny conditions were 11.76, 15.89 and 19.11ºC, respectively.

Keywords


[3] M. Aghbashlo, M.H. Kianmehr, S. Khani, and M. Ghasemi, Mathematical modelling of thin-layer drying of carrot. International Agrophysic, 23 (4), 313-317, 2009.
[4] P.T. Patak,  Thin layer drying model for rapeseed. Transactions of The ASABE. l34 (6), 2505-2508, 1991.
[5] Sun, D.W., and Woods, J.L. 1994. Low temperature moisture transfer characteristics of wheat in thin layers. Transactions of the ASABE, l37 (6), 1919-1928.
[6] H. Karami, M. Rasekh, Y. Darvishi, and R. Khaledi, Effect of Drying Temperature and Air Velocity on the Essential OilContent of Mentha aquatica L. J. Essen Oil Bear Plant., 20(4): 1131-1136, 2017.
[7] V. Demir, T. Gunhan, and A.k. Yagcioglu, Mathematical modeling of  convection drying of green table olives. Biosystems Engineering, 98, 47-53, 2007.
[8] I. Doymaz, The kinetics of forced convective air-drying of pumpkin slices. Journal of Food Engineering, 79, 243–248, 2007.
[9] K.E. Akpinar, Y. Bicar, and C. Yildiz,  Thin layer drying of red pepper. Journal of Food Engineering, 59, 99-104, 2004.
[10] H. Karami, M. Rasekh, and Y. Darvishi, Effect of temperature and air velocity on drying kinetics and organo essential oil extraction efficiency in a hybrid dryer. J. Innovative Food Technologies., 5(1): 65-75, 2017.
 [12] AOAC, Official Methods ­­of Analysis. Association of Official Analytical Chemists Press.  Washington , DC, 1984.
[13] E.  Mirzaee, S. Rafiee, A. Keyhani, Evaluation and selection of thin-layer models for drying kinetics of apricot (cv. NASIRY).  CIGR Journal, 12, No.2, 2010.
[14] M. Aghbashlo, M. Kianmehr, and H. Samimi-Akhijahani, Evaluation of thin-layer drying models for describing drying kinetikc of barberries (barberries vulgaris). Journal of  Food Process Engineering, 32(2), 278-293, 2009.
[15] V.T. Karathanos, Determination of water content of dried fruits by drying kinetics. Journal of Food Engineering, 39, 337-344, 1999.
[16] O. Yaldız, C. Ertekin, and H. I. Uzun, Mathematical modeling of thin layer solar drying of Sultana grapes. Energy, 26(5), 457– 464, 2001.