CFD modelling of almond drying in a tray dryer

Abstract

Drying is important in many food processing applications, and particularly so in the dry fruits industry. This work is focused on developing computational models for simulating the drying of almonds in a tray dryer. It is important to quantitatively understand heat and mass transfer within and around a single almond particle as well as the particle‐particle interactions and their implications for dryer design. In this work, we have developed a systematic CFD modelling framework for modelling almond drying in a tray dryer. A single tray filled with almonds (∼2 kg) were dried at three set temperatures viz., 55, 65, and 75 °C. Air relative humidity at the inlet and outlet locations, and the weight of almonds were measured during drying for each experiment. An additional set of experiments were conducted in which almonds were filled only in the half section of the tray, keeping the other half empty. The same amount of almonds were used, to have multiple layers of almonds in the tray, and the set temperature for the experiment was 75 °C. Flow, heat, and mass transfer in the tray dryer were simulated using commercial CFD software Ansys Fluent. The validated computational model was used to simulate various cases including larger and more trays. The developed approach and models will be useful to select the appropriate dryer configuration and optimize its design. The developed models will also be useful to identify suitable operation conditions for the drying of almonds as well as other food products.

A Comprehensive Review of Mathematical Modeling for Drying Processes of Fruits and Vegetables

“…A number of commercial CFD software such as COM-SOL, ANSYS, MATLAB, and FORTRAN, among others, are widely used to simulate the model of drying processes [23,43,53,54]. Employing response surface methodology (RSM), the drying behavior of fruits and vegetables, was optimized and different process factors were studied [55][56][57][58].…”

Effect of Immersion Concentration in Salt Solution, Drying Time and Air Velocity on Drying Wet Noodles Using a Tray Dryer and Solar Assistance

“…Drying can also increase food stability and minimize physical and chemical changes during storage [7,8]. Drying is a complex process involving heat and the transfer of moisture in the product to the surface of the material and then to the surrounding medium [9]. Dry noodles can be produced using a controlled drying process in a room where the parameters of temperature, humidity and ventilation are regulated [10].…”

CFD-response surface methodology to optimize the effective thermal conductivity and homogeneity in tray dryer

“…In addition, increments in air velocity used to solve this problem lead to higher energy costs (Tzempelikos et al 2012). These issues have been reported in convective dryers in both simulations and experimental validations; however, due to their low manufacturing cost, they are still widely used in developing countries (Esparza E. Traditional kinetics models do not account for the influence of flow and transport properties, which are based on the geometrical configurations and operating parameters of tray dryers (Chilka & Ranade, 2018). Therefore, 3D models of dryers have been created in CFD and experimentally validated by several researchers.…”