International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This study details the thermal and fluid dynamic performance analysis and geometric optimization of a compact plate heat exchanger designed for waste heat recovery in industrial drying systems. The objective is to preheat fresh process air (25oC) to a target temperature range of 65–70 oC by recovering heat from high-temperature exhaust air (84 oC inlet, 36,000m3/h flow rate). The methodology integrates fundamental thermodynamic assessment (LMTD and  methods) with Computational Fluid Dynamics (CFD) for detailed flow and temperature mapping. Critically, a Differential Evolution (DE) algorithm was applied to optimize plate geometry, channel size, and profile arrangement, subject to a mass constraint, to maximize heat transfer. Results confirm that the optimized design achieves 18-25% natural gas savings and 27.5% higher efficiency compared to conventional systems. This hybrid approach validates the optimized heat exchanger as a highly sustainable and economically viable solution for industrial thermal management.