Process calculation method and optimization of the spiral-wound heat exchanger with bilateral phase change

Highlights: • A method of subsection calculation is presented. • The optimal design based on the genetic algorithm is carried out. • The optimized heat transfer area was reduced by about 23.4%. - Abstract: Aiming at the complexity of the process calculation of the spiral-wound heat exchangers (SWHEs) with bilateral phase change, a method of segmented calculation is presented. According to the general working conditions of oil refinery, the engineering calculation model is established. The optimal design of the spiral-wound heat exchanger is carried out, based on the genetic algorithm. When the total heat transfer capacity is constant, the total heat exchange area is used as the objective function, and the winding angle $\alpha$ (10–30°), the thickness of the spacer a (0–10 mm) and the axial tube spacing of the same layer c (0–10 mm) are taken as the design variables. When the heredity is given to a certain algebra, the heredity terminates, the a value is 0.00237 m, the c value is 0.00814 m, the $\alpha$ value is 11.7°, and the objective function is the total heat exchange area, which is 4900.6 m². The optimization results show that the optimized heat transfer area is reduced by about 23.4%, The tube side and shell side pressure drop are within the allowable range, although increased.