Study on calculation method of condensation heat transfer for non-azeotropic hydrocarbon mixtures in helically coiled tubes

In order to study the condensation heat transfer characteristics of non-azeotropic hydrocarbon mixtures in helically coiled tubes for large-scale spiral-wound heat exchangers, a simplified physical model of three-section helical tubes was proposed. Reasonable governing equations and boundary conditions were set up, and the grid independence was verified. Then, the condensation heat transfer characteristics of mixture refrigerants were analyzed. In addition, considering the effect of mass transfer resistance of non-azeotropic mixtures on heat transfer during condensation, a method combining numerical simulation with the Bell and Ghaly correction method was proposed to calculate the condensation heat transfer coefficient of mixtures. By comparing with the experimental results, the accuracy of the calculation model is verified, which provides theoretical support for the design of large-scale spiral-wound heat exchangers.