ผลกระทบของห้องอบสองชั้นต่ออุณหภูมิและความชื้นสัมพัทธ์ในกระบวนการอบแห้งกล้วยน้ำว้าด้วยโรงอบแห้งพลังงานแสงอาทิตย์

Abstract

The objective of this research was to find out the outputs of dried product by the solar drying using the single-drying chamber comparing to the double-drying chamber. The bananas (Musa ABB) was used as a sampling in the testing of the natural convection and the forced convection. The initial moisture content was 65-67 % w.b., dried until less than 20 % w.b. The studies showed that the double-drying chambers could internally distribute the temperature well, and consistently similar in all layers. Its thermal efficiency is better than the single-drying chamber.  Its specific energy consumption was less than the one of the single-drying chamber. The specific energy consumption of the double-drying-chamber conditioned by including the infrared heater and compared between turning on and turning off the ventilation fan was 2.52 and 2.19 kWh/kg, respectively. The solar drying with infrared heater and turn of the ventilation fan, it took less than 2 days to dry the bananas which had moisture content to 20 % w.b. The color values of the product dried with the inclusion of the infrared heater were the darkest color, its lighting value decreased and the red value increased, both statistically significant (P ≤ 0.05)