Thermal–Hydraulic Performance Analysis of Smooth and Corrugated Helical Coil Heat Exchangers Using Mathematical and Numerical Approaches

Abstract

The growing demand for compact, efficient, and sustainable thermal management systems has led to a growing interest in helical coil heat exchangers due to their superior heat transfer characteristics. The influence of the Dean number and Colburn factor on heat transfer and flow behavior is examined, emphasizing the role of induced secondary flows. A mathematical model was developed to compute Nusselt number, friction factor and pressure drop using modified correlations for corrugated geometries. Numerical simulations using ANSYS Fluent revealed that corrugated tubes enhance Nu by up to 32% compared to smooth tubes. Mathematical correlations are developed based on governing equations of mass momentum and energy equation. the thermal-hydraulic performance factor peaked at 1.38 near De ≈ 734. The coefficient of performance improved by 19–26%, with a 0.12 m coil diameter delivering optimal efficiency. Results showed strong agreement (RMSE < 4%), validating the approach.