Patent ID: 8826970

Claim:
A heat exchanging system, comprising: a heat exchanger including a tube for a first fluid to flow therethrough and a plurality of fins that are formed of thin plates, that are attached to the tube, and that are arranged side by side in an extending direction of the tube; and a fan for introducing a second fluid between the fins, wherein the fins meander so as to have continuous concave and convex parts formed at a regular pitch, the concave and convex parts are arranged so as to extend in a direction intersecting a passage direction of the second fluid passing between the fins, and a flow rate of the second fluid passing between the fins is made variable at a regular cycle so as to bring about, at a regular cycle, a first state where a vortex stays in the concave part and becomes stagnant and a second state where a portion of the vortex extends out of the concave part due to a decrease in angular velocity of the vortex and heat exchange is performed between the portion of the vortex and a flow of the second fluid flowing between the fins.