Numerical Simulation of Heat and Moisture Transfer in Corrugated Walls Dryer

Abstract

The primary goal of the current work is to model heat and mass transfer during mango drying in a wavy airflow dryer. By modifying the dryer walls, we were able to produce the undulating airflow (with V-shaped obstacles). With convective boundary conditions applied to all product surfaces, the explicit finite difference approach was used to study heat and mass exchanges in two dimensions during the drying of mango slices. During drying, the transfer coefficients are thought to fluctuate. Using EasyCFD software, the external flow, temperature, velocity, and pressure fields were then analyzed. This provided the profile of the heat transfer coefficient. These profiles were then utilized to calculate the mass transfer coefficient using the Shilton-Colburn analogy. Moreover, the code created to determine the heat and mass transfer coefficients in the product was used to derive the evolution of temperature and moisture content over time. The results allowed for the discovery of a new air flow in dryers called an undular flow and demonstrated how modifying the drying air stream enhanced heat transfer efficiency. By changing the air flow in the dryer, it was possible to achieve heat transfer coefficients ranging from 47.55 W/m²K to 357.38 W/m²K and mass transfer coefficients of 3.21 x 10-5 to 3.21 x 10-4 m²/s. When the outcomes of this investigation were compared to experimental results from the literature (under identical drying circumstances), a reasonable level of adequacy was discovered.