| 摘要 |
PURPOSE:To lower the heat resistance of fins and, at the same time, to lower the circulation resistance of an air stream by providing lower-shaped or bridge-shaped slotted ridges opened in the direction of the air stream continuously between heat transfer tubes and at a part of fins between columns, and so constituting that the legs of these slotted ridges connected to the fins have an angle of inclination with respect to the cut side in front or at the rear of the fin. CONSTITUTION:Air flowing from one direction 15 carries out indirect exchange of heat transmitted from a coolant through fins upon passing between fins. Since cut-and- rises 13 are provided from the upstream side to the downstream side, the air flow is divided into two parts, that is, one flowing in the inner part of the cut-and-rise 13 and another flowing in the outer part thereof, and a turbulence is created and, at the same time, the pressure loss is lowered. Further, legs 13a and 13b of the cut-and- rises 13 which are connected to the fin 12 have an inclination with respect to the air stream. Therefore, an interference is produced between the air stream which comes into collision with the legs and another which passes therebetween and a vortex is generated. Mixing of the turbulences due to the slips of these flows and air streams between fins remarkably decreases the heat resistance on the surfaces of fins 12. |
