Design and Simulation of a Fluidized Bed Dryer for Saffron Drying with an Approach to Reducing Energy Consumption

Document Type : Original Article

Authors

1 Doctoral student of Islamic Azad University, Science and Research Branch, Tehran Branch

2 Department of Biosystems Engineering, Science and Research branch, Islamic Azad University, Tehran

3 Department of Agricultural mechanization, Science and Research Branch, Islamic Azad University, Tehran, Iran

10.48308/pae.2025.236532.1085

Abstract

Today, the development of food systems and agricultural goods is often the largest contributor to national economies and plays a key role in achieving sustainable development goals. Meanwhile, food and nutrition are essential to citizens' health, and food preservation specialists are systematically working toward progress in creating a more sustainable system. Saffron is a highly valuable spice extracted from the flower's stigma. Drying is a crucial process in saffron production, as it helps preserve the spice's flavor, aroma, and color. Proper storage helps maintain the quality of saffron over a long period. In this study, the Computational Fluid Dynamics (CFD) method was used to model the saffron experimental Fluidized bed dryer. The behavior of the fluid within the dryer was examined utilizing computational fluid dynamics and the turbulent flow ε-k as a turbulence model using the Fluent software. The device was simulated at three different air temperatures—60, 65, and 70 oC—and three different air speeds: 1.5, 52.5, and 5.3 m/s. Results of analysis of the coefficient of variance of inlet air temperature and dryer air velocity on humidity with Mean square humidity (20.96) demonstrated that better results are attained when the dryer's air speed is lowered and its input air temperature is raised, or vice versa. Thus, if a dryer is manufactured, it needs to be able to change both the speed and the temperature to reach 10% humidity (wetness-based).

Keywords


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