Empirical correlations for drying kinetics of some fruits and vegetables

被引:65
作者
El-Sebaii, AA [1 ]
Aboul-Enein, S [1 ]
Ramadan, MRI [1 ]
El-Gohary, HG [1 ]
机构
[1] Tanta Univ, Fac Sci, Dept Phys, Tanta, Egypt
关键词
D O I
10.1016/S0360-5442(02)00021-X
中图分类号
O414.1 [热力学];
学科分类号
摘要
An indirect type natural convection locally made solar dryer, consisting of a flat-plate solar air heater connected to a drying chamber, has been investigated experimentally and theoretically. The system is used for drying fruits and vegetables such as seedless grapes, figs, green peas, tomatoes and onions. The experimental data are used to calculate the drying constants k for the selected products. The obtained values of k are then correlated with the drying product temperature T-dp. Linear correlations between k and T-dp are found to satisfactorily describe the drying curves of the materials under study. Furthermore, the characteristics constants c and n of Henderson's equation are determined for the selected crops using the experimentally measured relative humidity of the drying air. A simple mathematical model is presented for the drying chamber based on the energy and mass balance equations and employing the proposed correlations for k as well as the values of the constants c and n. Numerical calculations are performed on typical summer and winter days in Tanta. Comparisons between experimental and theoretical results showed that good agreement has been achieved. The effect of the mass of the drying product m(dp) on the dryer performance is also investigated by computer simulation. (C) 2002 Elsevier Science Ltd. All rights reserved.
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收藏
页码:845 / 859
页数:15
相关论文
共 27 条
[1]   Parametric study of a solar air heater with and without thermal storage for solar drying applications [J].
Aboul-Enein, S ;
El-Sebaii, AA ;
Ramadan, MRI ;
El-Gohary, HG .
RENEWABLE ENERGY, 2000, 21 (3-4) :505-522
[2]  
ADARA E, 2000, INT J ENERG RES, V24, P32
[3]   SIMULATION OF THE INDIRECT NATURAL-CONVECTION SOLAR DRYING OF ROUGH RICE [J].
BALA, BK ;
WOODS, JL .
SOLAR ENERGY, 1994, 53 (03) :259-266
[4]   Thin layer drying rate and loss of viability modelling for rapeseed (Canola) [J].
Corrêa, PC ;
Martins, JH ;
Christ, D .
JOURNAL OF AGRICULTURAL ENGINEERING RESEARCH, 1999, 74 (01) :33-39
[5]   MATHEMATICAL-MODELING OF THE THIN-LAYER SOLAR DRYING OF SWEET-POTATO SLICES [J].
DIAMANTE, LM ;
MUNRO, PA .
SOLAR ENERGY, 1993, 51 (04) :271-276
[6]  
EKECHUKWU OV, 1990, ENERGY CONSERV MGMT, V40, P593
[7]   MATHEMATICAL-MODELING OF A THIN-LAYER SOLAR KILN [J].
ELSAYED, MM .
JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME, 1990, 112 (03) :196-203
[8]  
ELSEBAII AA, IN PRESS ENERGY CONV
[9]  
Exell R.H.B., 1980, RENEWABLE ENERGY REV, V1, P1
[10]  
Garg HP, 1998, INT J ENERG RES, V22, P1165, DOI 10.1002/(SICI)1099-114X(19981025)22:13<1165::AID-ER442>3.0.CO