Influence of fluid distributors on the performance of the industrial cold box with a plate-fin heat exchanger: A numerical study

Abstract

The cold box, which comprises of several plate-fin heat exchangers (PFHE), is largely utilized in different industries. In this research, the computational fluid dynamics (CFD) technique has been used for investigating the impact of different fluid distributors on the rates of heat and mass transfer, in an industrial complex cold box equipped with plate-fins. While inlet and outlet fluid distributors and channels were taken into account in the computational domain, the porous media technique was applied to the channels as an alternative to the fins in the original cold box. The mass transfer model including the phase change was accounted for by the flash calculations. Local thermal non-equilibrium (LTNE) between the porous medium and fluid flow with a mass transfer was used in the simulations. Three principal side distributors, i.e. diagonals A, B, and C, were used, and their performance was evaluated by CFD. It was found that using each of these types of distributors led to different CFD results in the cold box. The heat transfer rate in the case of the diagonal C was 73% more than that of the diagonal A. The flow uniformity index in the case of the diagonal C was 11.6% greater than that of the diagonal A in the stream C.