Structural parameter design of welded plate heat exchanger based on multi-objective optimization algorithm

A numerical investigation was conducted to explore the heat transfer and flow characteristics of welded plate heat exchanger with chevron sinusoidal corrugated plates and to find the optimal parameter design in this paper. For better thermo-hydraulic performance, the effects of chevron angle (& beta; = 30 degrees ,45 degrees ,60 degrees), the height of the corrugations (H = 3,5,7,9) and the pitch of corrugations (P = 15,20,30,45,60) were studied with inlet velocity ranged from 0.1 m/s to 0.5 m/s. Moreover, artificial neural networks (ANNs) and multi-objective genetic algorithm (MOGA) were employed to obtain optimization solutions of the structural parameters. With the analysis of flow form inside the flow channel, it was proposed that the chevron sinusoidal corrugated plates were helpful to transform the axial velocity of fluid to radial velocity, forming turbulence and secondary flow in the narrow region. The numerical results showed that the comprehensive performance of the plate with & beta; = 45 degrees was better than the other two, while P = 30 mm and H = 9 mm also performed well in this paper. Besides, an optimal parameters set was obtained with P = 15.132 mm, H = 3.005 mm, & beta; = 45.495 degrees when the velocity of inlet was set as 0.1 m/s, the maximum JF could reach 0.034 as the results of multi-objective optimization.