Abstract: The present invention discloses a flooded type evaporating heat-exchange copper tube for an electrical refrigeration unit. The evaporating heat-exchange tube comprises a smooth surface portion, a finned portion provided with plurality of fins and a transitional portion connecting the smooth surface portion to the finned portion, with primary evaporating chambers defined between the fins. Fifth fins extending upwardly are provided on a bottom wall of the primary evaporating chamber, which divide the primary evaporating chamber into at least two minor cavities, and an evaporating opening is defined between adjacent fins of the primary evaporating chamber. Due to plurality of minor cavities arranged in the evaporating heat-exchange tube, refrigerant film is easy to form on bottom walls of the minor cavities, and nucleus boiling is easily to be developed. Thereafter, the refrigerant gets boiled and evaporated to form bubbles to escape via evaporating openings.

Abstract: The present invention discloses a condensing heat-exchange copper tube for a flooded type electrical refrigeration unit, which comprises a smooth surface portion, a finned portion provided with plurality of fins and a transitional portion connecting the smooth surface portion to the finned portion. Said fin includes a fin base close to the outer surface of the heat-exchange tube and a fin top away from the outer surface. Said fin is further provided with a secondary fin at the central portion of the fin and a third fin at the top portion of the fin, wherein a certain distance is provided between two axially adjacent secondary fins or two axially adjacent third fins. Secondary fins as well as third fins according to the invention further increase the heat transfer area for the heat-exchange tube. Meanwhile, secondary fins and third fins help to attenuate the condensate film such that the condensate film is substantially eliminated, and vapor condensation and heat transfer may be carried out in a better way.

Abstract: The present invention discloses a condensing heat-exchange copper tube for a flooded type electrical refrigeration unit, which comprises a smooth surface portion, a finned portion provided with plurality of fins and a transitional portion connecting the smooth surface portion to the finned portion. Said fin includes a fin base close to the outer surface of the heat-exchange tube and a fin top away from the outer surface. Said fin is further provided with a secondary fin at the central portion of the fin and a third fin at the top portion of the fin, wherein a certain distance is provided between two axially adjacent secondary fins or two axially adjacent third fins. Secondary fins as well as third fins according to the invention further increase the heat transfer area for the heat-exchange tube. Meanwhile, secondary fins and third fins help to attenuate the condensate film such that the condensate film is substantially eliminated, and vapor condensation and heat transfer may be carried out in a better way.