Experimental study and simulation of a solar dryer for spearmint leaves (Mentha spicata)

Benaouda Nour-Eddine, Zeghmati Belkacem, Khellaf Abdellah
2013 International Journal of Ambient Energy  
An indirect forced convection solar dryer consisting of an air flat plate collector and a drying cabined was designed and fabricated to investigate its performance under the climate of Algiers. Drying experiments have been performed for spearmint leaves at different air flow rate in order to determine the drying velocity, the characteristic drying curve, the effective diffusion coefficient and the activation energy. A mathematical model based on thermal and mass balances over the component of
more » ... e solar collector and the cabinet dryer was developed. Simulations are carried out for meteorological data of Algiers (Algeria). We analyze the effect of air mass flow rate, air temperature, products mass, collector area, air recycling rate on the drying time, the solar fraction and the efficiency of the dryer. Nomenclature Ac: collector area Cp: specific heat (J.kg -1 . K -1 ) CDC: characteristic drying curve D eff : Diffusion coefficient (m 2 . s -1 ) e: thickness (m) f: solar fraction (%) f*: dimensionless drying rate h: heat transfer coefficient (W.m -2 K -1 ) L V : latent heat of evaporation (J.kg -1 ) L: length (m) m: mass (kg) m  : air mass flow rate (kg s -1 ) P 0: porosity P: solar flux density (W.m -2 ) Q: quantity of heat (J) RH: air relative humidity (%) T: temperature (K) t: time (s) T R : air recycling rate (%) v: velocity (m.s -1 ) (1)
doi:10.1080/01430750.2013.820149 fatcat:cgjcl52edfhj5gc3difaaszrvi