Performance Investigation and Optimization of Spiral Heat Exchangers with Different Fluids by Response Surface Methodology

This study systematically examined the Spiral Plate Heat Exchanger (SPHE) and optimized its performance employing the Response Surface Methodology (RSM), mainly seeking to identify the optimal relationship of the Convective Heat Transfer Coefficient (CHTC) for four fluids—water, nitrobenzene, ethylene glycol, and oil—and evaluate the effects of fluid parameters like velocity, density, and viscosity. Using the Design of Experiments (DOE), the study revealed that fluid density and velocity positively affected CHTC, while viscosity had a negative impact. Key findings indicated that water and ethylene glycol had the highest and lowest CHTC, respectively. Regression analysis produced four semi-empirical linear equations, revealing a direct correlation between Mass Flow Rate (MFR) and CHTC and an inverse relationship with viscosity. Confidence intervals exceeding 95% confirmed the reliability of RSM results, with optimal equations achieving an error margin below 10% and a high accuracy of 90% for the derived coefficients. Overall, RSM is a valuable tool contributing to SPHEs’ optimal design.