Abstract: This heat exchanger is provided with an inner tube 2, a first flow passage 3 formed inside the inner tube 2, an outer tube 4 disposed coaxially with the inner tube 2 on the radially outer side thereof, a second flow passage 5 formed between the inner tube 2 and the outer tube 4, annular separating walls P1 to P4 which divide the second flow passage 5 into a plurality of spaces S1 to S5 in the axial direction of the outer tube 4, and space outlets E formed in one location in the circumferential direction of each separating wall P1 to P4, wherein the spaces S1 to S5 are configured to cause a second fluid to swirl about second axes Y perpendicular to a first axis X positioned at the center of the outer tube 4.

Abstract: This heat exchanger is provided with an inner tube 2, a first flow passage 3 formed inside the inner tube 2, an outer tube 4 disposed coaxially with the inner tube 2 on the radially outer side thereof, a second flow passage 5 formed between the inner tube 2 and the outer tube 4, annular separating walls P1 to P4 which divide the second flow passage 5 into a plurality of spaces S1 to S5 in the axial direction of the outer tube 4, and space outlets E formed in one location in the circumferential direction of each separating wall P1 to P4, wherein the spaces S1 to S5 are configured to cause a second fluid to swirl about second axes Y perpendicular to a first axis X positioned at the center of the outer tube 4.