5 kW@4.5 K氦低温系统一级板翅式换热器优化设计

Optimal design of the first stage of plate-fin heat exchanger for 5 kW@4.5 K cryogenic system

以5 k W@4.5 K制冷当量的CFETR TF线圈测试用的氦制冷机第一级主换热器为对象,采用混合遗传算法,在满足换热要求、压降限制、现有制造工艺和结构强度等前提下,对换热器的体积进行优化。结果表明,与常用的板翅式换热器商用软件Aspen MUSE^(TM)设计计算的结果相比,基于遗传算法的优化过程可以快速高效地搜索到以体积最小化为目标的全局最优解,其结构尺寸可由原先设计的4.485 m×0.900 m×0.863 m缩小到3.032 m×0.721 m×0.594 m。

With the growth of the refrigerating capacity for helium cryogenic system, the size of the heat exchanger is becoming important for consideration. The aluminum brazed multi-stream plate-fin heat ex- changer is the key compoment of the helium refrigerator, the size of which is important for the dimensions of the cold box. For the first stage of the heat exchanger for 5 kW@ 4.5 K helium refrigerator used in the test process of CFETR TF coils, the volume optimization of the heat exchanger is carried out based on hybrid ge- netic algorithm within the constraints of heat exchange requirements, maximum allowable pressure drop, ex- isting manufacturing techniques and structural strength. The results show that the optimization process based on genetic algorithm can quickly and efficiently search the global optimal solution compared with the com- mercial software Aspen MUSETM. The size decreased from the original 4. 485 m × 0. 900 m × 0. 863 m to the optimized 3. 032 m × 0. 721 m × 0. 594 m. The proposed method is very useful for optimization design of plate-fin heat exchanger.