Effect of structural parameter on heat transfer performance of coil-wound heat exchanger

The coil-wound heat exchanger has such advantages as high pressure resistance, smooth operation and strong fluid adaptability. The study on its heat transfer performance is significant to the enhancement of design and manufacturing capacity. In this paper, the geometric model, shell side heat transfer model and pipe side heat transfer model of the coil-wound heat exchanger are collected, the shell side structure factor and pipe side heat transfer coefficient of heat exchangers with different structural features and under different Reynolds numbers are calculated, and the variation of heat transfer characteristics with the structural parameters is analyzed. On this basis, the instructive proposals are put forward on ascertaining structural dimension in the course of design and manufacture. The study results show that the shell side heat transfer can be remarkably enhanced by reducing the shim thickness and the coil radial spacing. It is favorable for pipe side heat exchange by using macaroni coil and reducing the core diameter and wrapping diameter. Moreover, as to reducing the wrapping angle and coil axial spacing, it has limited effect on the enhancement of heat exchange, but it can reduce the height of heat exchanger and is thus convenient for transportation and installation.