Numerical Investigation for Y‐Shaped Twisted Inserts With Trapezoidal Perforations in Heat Exchangers

ABSTRACT This study introduces a novel Y‐shaped twisted insert with trapezoidal perforations, a numerical study was performed to investigate the thermal‐hydraulic performance of circular pipes equipped with Y‐shaped inserts, for heat transfer enhancement in circular heat exchanger pipes. employing computational fluid dynamics (CFD) with Ansys 2022‐R2 (finite volume method, k – ε turbulence model). Five geometric configurations cases (A, B, C, D, and E) variations included twisted Y‐strips (twist ratios 2 or 7), and trapezoidal perforations were analyzed under constant heat flux (1000 W/m²) with air as the working fluid across Reynolds numbers (Re) range (3000–21,000). Results demonstrated significant heat transfer enhancement, with case E (twisted Y ‐strip, twist ratio 7, 30 trapezoidal holes) achieving a peak Nusselt number (Nu = 197.673 at Re = 21,000), a 258% increase over the plain pipe (Nu = 55.23). Thermal Performance Factor (TPF) peaked at 3.863 (Re = 3000, case E), indicating superior efficiency at lower Re. Flow resistance reduction was observed, with case E exhibiting the lowest friction coefficient ( f = 0.016 at Re = 21,000). The synergistic effects of twisted geometries and perforations enhanced turbulence, fluid velocity, and heat dissipation. These findings underscore the efficacy of Y‐shaped inserts with optimized twist ratios and perforations in augmenting passive thermal performance while mitigating hydraulic losses, positioning case E as a promising configuration for energy‐efficient heat exchange systems. The results showed remarkable agreement with previous research on Y‐shaped inserts, reinforcing the credibility of the findings, which reflect scientific consensus in the field of heat transfer.