OPTIMAL CONTROL OF A DRYING UNIT BASED ON THE MAXIMUM PRINCIPLE
Abstract
This paper presents a mathematical and simulation-based approach to the optimal control of a drying unit by applying Pontryagin’s maximum principle. Drying processes in chemical engineering often involve complex interactions of heat and mass transfer, which makes process control challenging. The system under study is modeled as a second-order inertial system, and the control objective is to transfer the process output from an initial to a target state in minimum time, subject to constraints on the control input. Using the maximum principle, a bang-bang control strategy is derived and validated through numerical simulation. The results confirm that time-optimal performance can be achieved with simple switching control, making the approach suitable for implementation in industrial drying systems. The study highlights the practical benefits of optimal control for improving efficiency, energy use, and automation reliability in thermal processing applications.
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