Determination of Heat Transfer Coefficient and Effective Moisture Diffusivity of Phlai Drying

Abstract

The purpose of this research was to study the effects of far-infrared intensity on the change of moisture content of Phlai drying. Additionally, the heat transfer coefficient and effective moisture diffusivity of Phlai was investigated under combined heat pump and farinfrared radiation drying. The drying parameters for investigation were far-infrared radiation intensity of 1-4 kW/m2, drying air temperature of 40-60°C and drying air velocity of 0.5 m/s. The results showed that the moisture content of Phlai was reduced from initial moisture content of 420-500% d.b. to final moisture content of 6% d.b. The effective moisture diffusivity of Phlai was rapidly increased in the beginning of drying period and then remained constant with the increase kW/m2°C and 30-280 kW/m2°C for drying air temperature at 40, 50, and 60°C, respectively. The effective moisture diffusivity of Phlai were in a range of 0.11x10-10 - 0.84x10-10 m2/s.