แบบจำลองทางคณิตศาสตร์การอบแห้งข่าด้วยสุญญากาศร่วมกับรังสีอินฟราเรด

Abstract

This research studied to galangal drying using infrared-vacuum technique and to discover the appropriate thin layer equation for predicting the drying kinetic of galangal. To achieve these purposes, experiments were conducted on the following conditions: absolute pressure in drying chamber of 5 and 15 kPa and drying temperature of 45 and 55 ^oC. The effects of drying conditions on moisture ratio, drying rate, specific energy consumption and color of galangal were investigated. Furthermore, color quality of galangal was also explored. Experimental results shown that the drying rate shall be increased but specific energy consumption shall be decreased by reducing absolute pressure or increasing temperature. Moreover, the changing of color shall be affected from drying temperature which higher than boiling point of water. In addition, it was found that thin layer equation of Midilli providing the highest coefficient of determination (R²) by 0.99855 and the lowest of root mean square error (RMSE)      by 0.01201 and ² by 0.00029.