Numerical simulation of flow and heat transfer performance of tube-shell coupled helically coiled corrugated tube heat exchanger

To enhance heat transfer, this study proposes a new compound enhancement structure combining helical tube with centrosymmetric sinusoidal corrugations. A tube-shell coupled model of helically coiled corrugated tube heat exchanger (HCCTHE) is established. The impacts of Reynolds number, corrugation height, and corrugation length on flow and heat transfer performance are numerically analyzed by using Nusselt number (Nu), friction factor (f) and performance evaluation criterion (PEC) number. Findings indicate that the Nut and Nush for HCCTHE are up to 2.33 and 2.16 times higher than those of helically coiled smooth tube heat exchanger, respectively. As corrugation height increases, Nut, Nush, ft, and PEC number significantly increase. Conversely, decreasing corrugation length results in increased Nut, Nush, and PEC number, with insignificant impact on ft. As Ret increases from 0.81 x 104 to 4.86 x 104, and Resh increases from 0.24 x 104 to 2.4 x 104, the total increments in Nut and Nush with h/di = 0.1 and s/di = 3 are 294.14% and 228.49%. Furthermore, correlations for Nut, Nush, and ft are proposed. This study not only fills the gap in the shell-side flow and heat transfer characteristics of HCCTHE, but also offers theoretical reference for the design and optimization of HCCTHE.