In this study, a new technique for heat transfer enhancement through the introduction and analysis of a semicircle oblique-finned corrugated has been studied numerically. Different design parameters are employed, including the vertical gap ratio (H) of 0.03, 0.04, and 0.05, the horizontal gap ratio (V) of 0.15, 0.20, and 0.25, as well as oblique-angle (θ) of 10°, 20°, and 40° are examined. Finite volume method (FVM) and the κ-ε model are used to simulate turbulent air flows inside the targeted channels at constant temperature conditions (T = 300 K) over Reynolds number between 10,000–50,000. The findings indicate that the employment of the new technique resulted in increased heat transfer and, as a consequence, increased thermal-hydraulic performance (PEC) via improved fluid mixing. The results also indicate that the effect of frictional loss has been used to influence the target system's overall performance in the direction of minimising the effect of heat transfer. The results show that a small vertical gap ratio and a high horizontal gap ratio have a greater effect on both heat transfer rate and PEC than others. Generally, the best PEC of 2.469 has been observed when V = 0.15, H = 0.05, and = 40 are used as design parameters. In terms of Nusselt number and friction factor, new correlations for the new model of semicircle oblique-finned corrugated are also reported.