A conjugate fluid-porous approach to convective heat and mass transfer with application to produce drying

Abstract

A computational model capable of simulating heat and mass transfer in conjugate fluid-porous domains is utilized to simulate forced convective drying. The material to be dried is considered as the porous region, which is coupled through interfaces to the surrounding pure fluid region. The computational model solves transport equations for mass and momentum, energy, and moisture in all regions simultaneously. The model includes non-equilibrium heat and moisture transport in the porous region such that the fluid and solid constituents, and the exchanges between them, are captured. The interfacial moisture transfer condition between phases in the porous region, and between the porous and pure fluid regions, is developed to show the level of detail required for modeling. The study considers the drying of apple flesh to validate the developed drying model against available experimental data. The results show accurate prediction of moisture content as a function of drying time for different airflow velocities, and correctly capture the influences of temperature, relative humidity and initial moisture content on the drying rate. Thus, the model is considered viable for taking steps towards implicit dynamic coupling of the constituents in the porous region.

Convective drying of food materials: An overview with fundamental aspect, recent developments, and summary

“…There were a lot of numerical solutions developed by researchers on convective drying of food and other materials. The models have been developed for 1‐D Cartesian, 10,53,58,70 1‐D spherical, 66 2D, 11 and 3D 52 geometries. Few works used a CFD model for estimating the surface transfer coefficients and few of the works 25 based on experimental correlations.…”

“…A 3‐D model was developed for convective drying of apple by Khan and Straatman 52 . Heat and moisture transports were considered for solid pores, water, and water vapor inside the food product, therefore, it is a multiphase model.…”

“…This is also an assumption to solve the problem with simple manner, it may not predict the realistic picture. Few investigations have been reported in 3‐D formulations, 52 that too using simple models. On the other hand, adding further parameters and further dependence of other parameters increase the complexity of mathematical model, therefore, more lines of computer programs, more computational time, and requirement of a very good computing facility are necessary.…”

Drying of Almonds II: Multiple Particles

“…al [7] , for drying of deep-bed paddy drying process using CFD simulations. Conjugate heat and mass transfer for drying has been studied using CFD simulations by Khan and Straatman [8] .…”

Obtaining fruit-drying curves and CFD analysis for corozo (Bactris guineensis)

“…And other important properties such as mass diffusivity Louise E, et al [6] approximate the form of the biomass to geometry such as cylinders, spheres and hemispheres Torrez Irigoyen et al [7], thus obtaining linear and exponential models with high adjustment. Moreover, computational modeling has been a method used to study the behavior as a validation of the experimental characterization of the processes, which is why researchers such as A. Erriguible et al [8][9][10][11] did a simulation through the CFD tool to model water evaporation in porous media using the convective mechanism and developing the Navier-Stokes equations, obtaining the behaviors of pressure, temperature, mass flow and heat when using the drying models by convection in porous media.…”