MULTI-OBJECTIVE OPTIMIZATION OF HOT BLAST STOVE HEAT EXCHANGER

Abstract

Shell-and-tube heat exchangers are widely used in many research fields and industrial production processes, but little research has been conducted on the use of heat exchangers for drying crops. This study conducted a numerical simulation of the temperature, velocity, and pressure fields based on the shell-and-tube fluids of a heat exchanger in a biomass particle hot-blast stove. The correctness of the simulation results was verified by test data before simulation, and the mesh was verified to be irrelevant. The application of a multi-objective genetic algorithm in heat exchanger design and optimization was explored, considering five design variables, such as hot tube diameter, transverse pitch, longitudinal pitch, cold flow velocity, and hot flow velocity for optimization. The Nusselt number, friction factor, and comprehensive performance coefficient were used as objective functions for 2D and 3D response surface analysis. The final design variables P1=74.91 mm, P2=104.23 mm, P3=121.37 mm, P4=4.83 m/s, and P5=8.48 m/s were obtained to improve the comprehensive performance coefficient by 16.11%. The heat transfer performance was improved by 9.55% and the resistance performance was reduced by 15%.