초록 ▼

A heat-transfer tube with a grooved inner surface adapted to phase-transition for fluid flowing inside the tube disposed in a heat exchanger is disclosed. This tube can achieve the reduction in the weight per unit length, improvements in workability and characteristics of the tube by limiting the cr

A heat-transfer tube with a grooved inner surface adapted to phase-transition for fluid flowing inside the tube disposed in a heat exchanger is disclosed. This tube can achieve the reduction in the weight per unit length, improvements in workability and characteristics of the tube by limiting the cross-sectional area of respective grooved section and the shape of the ridge defining the grooved section.

대표청구항 ▼

In a heat-transfer tube with a grooved inner surface adapted to phase-transition of fluid flowing inside the tube and having a number of spiral grooves having a helix angle (b0.02 to 0.03, and the helix angle (b7°to 30°, the improvements comprising: each of said grooves being substantially trapezoid

In a heat-transfer tube with a grooved inner surface adapted to phase-transition of fluid flowing inside the tube and having a number of spiral grooves having a helix angle (b0.02 to 0.03, and the helix angle (b7°to 30°, the improvements comprising: each of said grooves being substantially trapezoidal in shape; the ratio (S/Hf) of the cross-sectional area (S) of respective grooved section to said groove depth (Hf) ranging from 0.15 to 0.40; each of said ridges being substantially triangular in cross-section; and the apex angle (a30°to 60°.