积灰对具有不同翅片结构的翅片管换热器均会造成长效性能的衰减。本文搭建了换热器积灰可视化实验台，研究了翅片结构对积灰量及积灰后空气侧压降的影响。测试样件的翅片类型包括平直翅片、波纹翅片和开窗翅片；翅片间距范围为1.3～1.8 mm。实验结果表明：开窗翅片管换热器表面最容易沉积粉尘并增大积灰后压降，与平直翅片相比，波纹翅片和开窗翅片表面粉尘沉积量分别提高了25.6％和52.8％、积灰后压降增量分别提高了44.4％和165.6％；对于开窗翅片，小翅片间距有利于积灰并增大积灰后压降，与翅片间距1.8 mm的样件相比，翅片间距1.5 mm和1.3 mm的样件表面粉尘沉积量分别提高了26.2％和43.2％、积灰后压降增量分别提高了24.1％和49.4％；在积灰过程中，随着粉尘沉积量的增加，翅片管换热器空气侧压降先增大后保持稳定。%The long-term performance of fin-and-tube heat exchangers with different fin structures will decay when covered with dust parti-cles. In this paper, a visual experimental rig was established to investigate the effects of fin structures on particle deposition and air-side pressure drop. The fin types of test samples covered plain fins, wavy fins and louver fins, and the fin pitches ranged from 1. 3 mm to 1. 8 mm. The results show that, louver fins are most beneficial to particle deposition;the maximum particle deposition weight on wavy fins and louver fins increased by 25. 6% and 52. 8% respectively compared with that on plain fins, meanwhile the increment of pressure drop in-creased by 44. 4% and 165. 6% respectively. Small fin pitch can promote particle deposition and increase pressure drop; the maximum particle deposition weight on louver fins with fin pitch of 1. 5 mm and 1. 3 mm increased by 26. 2% and 43. 2% respectively compared with that on louver fin with fin pitch of 1. 8 mm, meanwhile the increment of pressure drop increased by 24. 1% and 49. 4% respectively. The air-side pressure drop firstly increased then tended to be stable with the increase of particle deposition weight.
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