Performance enhancement of flat plate heat exchangers through baffle integration: Thermal, flow, and entropy analysis

Abstract

The Plate Heat Exchangers (PHEs) are of essential integral component in industries in diverse aspects and can handle even the minimal temperature differential. This study builds on previous research in a 500 × 2 MW Thermal Power Plant by introducing novel baffle designs in PHEs for the first time. These baffles were specifically developed to address the intricate geometry and complex flow dynamics of PHEs. Building on our previous work, an in-depth analysis was conducted to assess entropy generation, shear stress distribution, and the impact of these baffles on flow maldistribution and thermal performance, as quantified by the JF factor. The study employs the Realizable k-ε turbulence model with scalable wall functions, using the PISO algorithm for pressure-velocity coupling, with a second-order approximation for momentum transport equations and a first-order for turbulence equations. Results indicate a remarkable boost of 11.5 times thermal performance enhancement compared to conventional model. The wedge type experienced a turbulent kinetic energy (TKE) increase of up to 15 %, while the aerofoil exhibited a decrease of 18 %. Additionally, Witte-Shamsundar efficiency was evaluated and advanced regression models were used to predict the Nusselt number and skin friction coefficient, with Gaussian Process Regression (GPR) emerging as the most reliable model. The findings highlight the aerofoil baffles exhibited stable and consistent performance across multiple parameters unlike wedge baffles, enhancing heat exchanger performance along with effective energy utilization.