HEAT TRANSFER TUBE FOR HEAT EXCHANGER AND HEAT EXCHANGER

摘要

[Problem] To provide a heat transfer tube for a heat exchanger, which enables the heat exchanger to have a compact construction. [Solution] A heat transfer tube (11) for a heat exchanger is provided with: an outer tube (13); multiple inner tubes (15) inserted through the outer tube (13) so that the axes of the inner tubes are arranged with an equal distance from one to the other in a cross section orthogonal to the axes; a first coil (17) having at least a portion thereof fixed on an inner circumferential surface (21) of the outer tube, said multiple inner tubes (15) being inserted through the first coil (17); second coils (19) each having at least a portion thereof fixed on an inner circumferential surface (23) of each inner tube; a flow path cross-section area (S1) of a first flow path (25) defined by the inside of the outer tube (13) and the outsides of the inner tubes (15); and a flow path cross section area (S2) of second flow paths (27), defined by a total area of flow path cross sections of the inner tubes (15) and having a ratio with the flow path cross section (S1) such that S1:S2 = 1:2 to 2:1.