Fuzzy and Conventional Modeling of Open Sun Drying Kinetics for Roasted Green Wheat

Figures & data

Table 1  Conventional mathematical models for crop drying given by different authors

Model equation	Name	References
	Geometric	Chandra and Singh[29]
	Lewis	Lui and Bakker-Arkema[30]
	Page	Agarwal and Singh[31]
	Henderson and Pabis	Chhinman[32]
	Wang and Singh	Wang and Singh[33]
	Logistic	Chandra and Singh[29]
	Two-term exponential	Henderson[34]
MR: moisture ratio; k: drying coefficient specific to each model; k 1 and k 2: drying coefficients on two-term exponential equation; t: time; a, a 0, a 1, a 2: coefficients specific to each model; n: exponent specific to each model.

Figure 1 The seven trapezoidal membership functions for fuzzy model. (Color figure available online.)

Figure 2 Variation of ambient temperature with time during the day of experiment and in a typical day in the first week of May. (Color figure available online.)

Figure 3 Variation of moisture ratio with drying time during open sun drying of roasted green wheat. (Color figure available online.)

Figure 4 Variation of drying rate with time for roasted green wheat. (Color figure available online.)

Table 2  Thin-layer model fitting results for roasted green wheat

Model name	Model coefficients	R ^2	RMSE
Geometric	a = 0.63, n = 0.76	0.85	0.110
Lewis	k = 0.41	0.94	0.082
Page	k = 0.24, n = 1.53	0.984	0.038
Henderson and Papis	a = 1.11, k = 0.45	0.958	0.070
Wang and Singh	a 1 = −0.29, a 2 = 0.019	0.981	0.047
Logistic	a 0 = 1.34, a = 0.31, k = −0.84	0.987	0.039
Two-term exponential	a = 2.07, k = 0.66	0.988	0.038

Figure 5 Comparison between experimental and predicted moisture ratio for roasted green wheat sun drying using two–terms exponential model. (Color figure available online.)

Figure 6 Comparison between experimental and predicted moisture ratio for roasted green wheat sun drying using fuzzy modeling. (Color figure available online.)

Table 3  Comparison of moisture diffusivity of roasted green wheat with wheat and other grains

Crop	M.C.*(% w.b.)	Deff ** (m^2/s)	Reference
Roasted green wheat	43	1.7 × 10^−11	This study
Wheat	5–17	1.7 × 10^−10	Jaros et al.[23]
Wheat	—	5.1 × 10^−11	Gastón et al.[10]
White beans	11–38	1.1 × 10^−11	Adu and Otten[25]
Rough rice	—	2.3 × 10^−11	Zuritz and Singh[26]
Sorghum	—	2.8 × 10^−11	Suarez et al.[27]
Soybean	—	8.7 × 10^−11	Kitic and Viollaz[28]
*Wet based moisture content.
**Effective diffusivity.

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