Thermodynamic analysis of structural parameters during condensation in spiral tubes

In this paper, a two-phase flow experimental system is proposed based on the condensation flow of the hydrocarbon mixture in the spirally wound tube to study the characteristics of the mixture (methane/ ethane/propane) in the spiral tube. An investigation is conducted on the effects of spiral diameter (D), inner diameter (d) and helix angle (β) on heat transfer coefficient (h_mix) and friction pressure drop (ΔP_fric). Moreover, the performance evaluation criterion (PEC) is adopted to measure the effect of structural parameters. As indicated by this paper, h_mix decreases with the increase in β, d and D, whereas ΔP_fric changes more significantly with d. If d increases or β decrease properly, the PEC will increase, which is of high significance to the design of tube-wound heat exchangers. The results of this paper can provide a reference for investigating the mechanism of condensation heat transfer in spiral tubes and the design of spiral wound heat exchangers.