longitudinal flow shell heat exchanger;  geometric prototype cycle segment;  four-tube model;  Calculate fluid dynamics

Aiming at the current method of calculating shell-level fluid flow in bow-shaped baffle plate shell-and-tube heat exchanger using the concepts of distribution resistance and volumetric porosity, according to the structural characteristics and flow characteristics of longitudinal shell-range heat exchanger, the simplified calculation problem of numerical simulation of large-scale longitudinal shell-length heat exchanger was discussed, and the simplified calculation method of geometric prototype periodic segment model and four-tube model were proposed to solve the numerical simulation problem of large-scale longitudinal shell-range heat exchanger. Applying the simplified calculation method proposed in this paper, the general CFD software F LUENT is used to numerically simulate the flow and heat transfer of different structural parameters of the longitudinal shell heat exchanger, and the mesoscopic information of the flow field and temperature field of the heat exchanger is obtained, which provides a basis for the structural optimization design and development of novel heat exchangers for the longitudinal flow shell heat exchanger.