PURPOSE: To improve the heat transfer performance of the fins and control the liquid flow resistance by inclining the end of the fins which are raised from the base plate toward the tube relative to the flow direction, and making the inclination angle of individual fins increasingly greater from the upstream side toward the downstream side of flow.
CONSTITUTION: The inclination angle α of the end of the raised part 6a is made 20°<α1<35°, and the inclination angel of the end of the raised part 7a is made 35°<α2<70°. The fluid made up with air enters from the leading edge 2a of a fin 2 in the direction A which is normal to the length of the fin 2. The fluid flows along the end of the raised part 6a of an individual fin 6 which is inclined at the angle α1 toward the tube 1 relative to the flow direction A. The fluid further flows along the end of the raised part 7a of an individual fin 7 which is inclined at the angle α2 toward the tube 1 to flow into the downstream side of the tube 1. Because of this, the dead zone 8 generated on the downstream side of the tube 1 becomes substantially smaller, improving the heat transfer performance of the fin 2 and reducing the configuration resistance of the tube 1.
SAKUMA KIYOSHI
TEZUKA YOFUMI
AOKI KATSUYUKI
YAMADA MAKOTO
FUJII MASAO
MORINUSHI KEN
