热泵空调翅片管换热器流路优化研究进展

Review on research status of circuit optimization of finned tube heat exchanger in heat pump and air conditioning

换热器的性能提升对制冷与热泵系统能效的提升具有重大影响,其中翅片管换热器的流路优化由于无需额外的成本、易于操作,是换热器性能提升的重要研究方向。本文总结了国内外学者对翅片管换热器流路的优化方法和评价指标。主要方法有基于空气侧风速分布的优化以及制冷剂侧流量的优化,基于管路结构的优化(包括管径、管路分合点、可变流路),基于微元换热最大化的优化,基于不可逆损失最小的[火用]分析、熵产最小化、热阻平衡法以及遗传算法的优化。总结得出可变流路可以同时满足蒸发器与冷凝器的最佳流路,是冷暖两用制冷与热泵系统流路优化的最佳选择;此外,热阻平衡法可以同时优化蒸发器与冷凝器的流路,是当前适用性较好的优化方法。评价指标中等泵功率下换热量的大小与热阻平衡是较为通用的评价指标。基于上述分析,针对翅片管换热器的优化方法以及评价指标提出了展望与建议。

The performance improvement of the heat exchanger has a significant impact on the improvement of the energy efficiency of the refrigeration and heat pump systems.The circuit optimization of the finned tube heat exchanger is an important research direction of heat exchanger performance improvement because of no extra cost and easy operation.This paper summarizes optimization methods and evaluation indexes of the finned tube heat exchanger circuit.The main methods are the optimization of the wind speed distribution on the air side,the flow rate on the refrigerant side,and the pipeline structure including the pipe diameter,the pipe splitting point,and the variable circuit.Other methods are the optimization based on maximization of micro-element heat transfer,based on exergy analysis with minimum irreversible loss,minimization of entropy generation,thermal resistance balance method and genetic algorithm.It is concluded that the variable flow path can meet the optimal circuit of the evaporator and the condenser at the same time,and is the best choice for the optimization of the circuit of the cooling and heating dual-purpose refrigeration and heat pump systems.In addition,the thermal resistance balance method can optimize the circuit of the evaporator and the condenser at the same time,which is the current optimization method with good applicability.The amount of heat transfer under the same pump power and thermal resistance balance are general evaluation indexes.Based on the above analysis,prospects and suggestions are put forward for the optimization method and evaluation index of the finned tube heat exchanger.