JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, cilt.29, sa.2, ss.433-441, 2014 (SCI-Expanded)
In this study, drying of bay leaves and system analysing were aimed in a closed cycle heat pump dryer. The bay leaf that has a high potential in Turkey, grows in Mediterranean and Aegean regions. Drying air relative humidity, temperature and air velocity which were entered from Programmable Logic Controller (PLC) screen, controlled according to set value. Six different experiments were done in a heat pump dryer at 40 degrees C, 45 degrees C and 50 degrees C drying air temperatures and 1 m/s and 1.5 m/s drying air velocities. Relative humidity of drying air was kept between the 4-11 % during the experiments by using dehumidification unit. The highest coefficient of performances (COPts) of whole system was calculated as 3.02 at 45 degrees C -1 m/s at the end of the experiments. Water activity values of dried bay leaves were measured between the 0.49-0.55.