Indirect cooling circuit via heat exchanger allowing optional heat recovery for the calorifier or cabin heating.

间接排气管冷却方式，经热交换器时，允许经任意方向通过与废气热交换器或散热箱。

Studies on heat exchanger aluminum fin precoat of air conditioner were reviewed. Six types of precoat as well as the application of hydrophilic precoat were described.

回顾了空调机热交换器预层铝散热片研究概况，介绍了6种类型预层散热片材料基本情况以及亲性预膜散热片效果。提出了该课题今后研究方向。