| Plate-fin heat exchangers have important applications in the field of petroleum chemical industry, transportation, machinery manufacturing, refrigeration, and aerospace for they have the advantage of compact structure and high thermal efficiency.The behavior of flow and heat transfer interacts with each other in a plate-fin heat exchanger. The flow resistance in a plate-fin heat exchanger is large and the manufacturing and operation cost is high. Therefore it’s important to optimize the multiple parameters including the heat transfer efficiency, the weight and the cost to improve its application in the related filed mentioned above. In view of this, in this paper the performance of plate-fin heat exchanger is optimized based on single-objective and multi-objective optimization algorithm.The process of genetic algorithm is introduced and the effect of different population, crossover operator, mutation operator is investigated in this paper.The treatment of the constraint conditions is given. And the multi-objective evolutionary algorithm is introduced. A numerical example is given to demonstrate two kinds of optimization algorithm, which established the basis for heat exchanger in optimization.The structure and key components of plate-fin heat exchanger were introduced in this paper, and the flow and heat transfer characteristic of the plate-fin heat exchangers are analyzed. The three kinds of evaluation methods including the entropy analysis, anergy analysis, and thermal economics analysis is given and compared. Based on the above evaluation method, the single objective and multi-objective parameter optimization method for a plate-fin heat exchanger are determined. The single objective optimization uses the heat transfer entropy production as the objective. For the Multi-objective optimization, heat transfer entropy production and resistance entropy production, efficiency and weight, efficiency and economic index were used as the objective function. The calculation results of the single objective and multi-objective parameter optimization are compared. The calculation results show that the multi-objective parameter optimization of plate-fin heat exchanger has dramatically improved the comprehensive performance. The results can provide guidance for the optimal design and application of plate-fin heat exchanger. |
