Drying is a complex thermal process in which unsteady heat and moisture transfer occur simultaneously [3]. From an
engineering point of view, it is important to develop a better understanding of the controlling parameters of this complex
process. Mathematical models of the drying processes are used for the control of the drying process. Many mathematical
models have been proposed to describe the drying process, of which thin-layer drying models have been widely in use.
These models can be categorized as theoretical, semi-theoretical, and empirical [14, 22]. Recently, there has been a lot of
research in mathematical modeling and experimental studies of the drying characteristics of various vegetables and fruits.
Studies on the sun drying of okra are scarce in the literature. Therefore, the present study was undertaken to study the drying
kinetics of okra in hot air dryer to evaluate a suitable drying model for describing the drying process.