| 摘要 |
PURPOSE:To improve a heat transfer rate on the air side, and to miniaturize a heat exchanger with fins and enhance its performance by alternately forming cut and erected sections opposite to an air current and cut and erected sections opening in the direction of the air current to the plate fins among heat transfer tubes. CONSTITUTION:I-shaped cut and erected sections 8 opposite to an air current, louver- shaped cut and erected sections 10 opening in the direction of the air current, I-shaped cut and erected sections 9 and louver-shaped cut and erected sections 11 are arranged in the order to fins 5 in clearance sections among heat transfer tubes 7 adjacent in the stepped direction of a heat exchanger with the fins from the upstream side of the air current. A plurality of small holes 12 are formed to the I-shaped cut and erected sections 8, 9. The fins 5 short in the direction of the air current and the louver-shaped cut and erected sections 10, 11 are positioned under an arranged state, and thin thermal boundary layers are formed severally. The disturbance of the air current on the downstream side is promoted by blow-off flows passing in the small holes 12. Peeling from the heat transfer tubes 7 of the air current in the surroundings of the heat transfer tubes 7 is prevented by flows crossing the side surface sections 9a of the I-shaped cut and erected sections 9, and a heat transfer rate on the air side is improved remarkably. |
