Generalized Mathematical Model of the Grain Drying Process

Abstract

Convective cereal grain drying is an energy-intensive process. Mathematical models are applied to analyze and optimize grain drying processes in different types of dryers and in different stages of drying to improve final grain quality and reduce energy consumption. The aim of the present study was to develop a generalized mathematical model of the grain drying process that accounts for all drying stages, including loading and unloading of unprocessed grain, drying, and cooling of dry grain. The developed mathematical model is a system of algebraic equations, where the calculated coefficients are determined by the thermophysical and diffusive properties of dried grain. The model was validated for batch drying of wheat, canola, and corn grain, as well as continuous flow drying of wheat grain. The results were compared with published findings. The relationships between energy consumption during drying and drying time vs. air temperature at the dryer inlet and air stream volume were determined. Dryer capacity and drying conditions specified by the manufacturers, as well as loading and unloading capacity, were considered during batch drying. Continuous flow drying simulations were conducted in counter-flow, parallel-flow, and cross-flow mode. Simulation results indicate that the proposed models correctly depicted process flow in both batch and continuous flow dryers.

Changes in Moisture Desorption Rate of Shelled Corn Layers in a Low-Temperature Deep-Bed Drying Column

“…There are numerous available food drying mathematical models such as the Page equation, the Newton model, the Wang and Singh model, and so on [5,7]. A number of empirical equations developed have as good, or greater, accuracy in a specific application with less computational effort compared with theoretical equations [8][9]. The exponential drying equation has been useful in certain cases for describing thin-layer drying though it provides a poor description of the initial part of the drying process [10].…”

Mathematical modeling of Brazilian black soybean: Lumped and distributed parameter models

“…The main parameters and objectives to be maximized/minimized can actively change throughout the drying process (Amantea et al, 2023). Convective drying (CD) models for seed layers consider the shape and size of individual seeds and are normally applied to describe the drying process of specific seeds (Myhan & Markowski, 2022). The variability of experimental data, the reduction of errors generated during experimentation, the improvement of the drying process, the minimization of energy demand, and the increase in profitability, are explained by the convective drying (CD) models (Cosme‐De Vera et al, 2021).…”

“…Thus, the basic approach of drying models is the laws of transport phenomena. In some cases, these models also account for the unequal distribution of selected seed parameters (Myhan & Markowski, 2022). Lumped parameter (LP) and distributed parameter (DP) models are the categories of equations that are applied to modeling thin seed layers (Myhan & Markowski, 2022).…”

“…Thus, the basic approach of drying models is the laws of transport phenomena. In some cases, these models also account for the unequal distribution of selected seed parameters (Myhan & Markowski, 2022).…”

“…Lumped parameter (LP) and distributed parameter (DP) models are the categories of equations that are applied to modeling thin seed layers (Myhan & Markowski, 2022).…”