Plate fin heat exchangers belong to inter wall heat exchangers. It is a compact and efficient heat exchanger with an all aluminum structure, with each channel composed of partitions, fins, guide vanes, and seals. Place fins and guide vanes between adjacent partitions, and seal both sides with seals to form a interlayer called a "channel". Multiple interlayers are stacked or arranged in different ways to form many parallel channels. At both ends of the channels, guide plates for cold and hot flow inlet and outlet are added, and they are welded together by brazing to form a group of plate bundles (or units). Coupled with fluid inlet and outlet heads and pipeline joints, a complete plate fin heat exchanger is formed.
The corrugated fins in the middle of the partition serve to support the partition and increase its strength; On the other hand, it also expands the heat transfer area, greatly increasing the heat transfer area per unit volume, making the entire heat exchanger compact. Fluid flows through channels within the fins. Due to the need to achieve heat exchange between cold and hot fluids in the heat exchanger, the channels for the cold and hot fluids need to be arranged at intervals.
Cold and hot fluids flow through different channels simultaneously, conducting heat transfer through partitions and fins, hence it is called a plate fin heat exchanger, also known as a compact heat exchanger. It is the most widely used heat exchanger in air separation plants today (except for high-pressure ones).
