Heat exchanger and method for manufacturing the same

A heat exchanger comprising:

• a first flow path surrounded by a first flow path wall;
• a second flow path surrounded by a second flow path wall formed separately from the first flow path wall;
• and
• a third flow path formed by a space between the first flow path wall and the second flow path wall,
• wherein the first flow path is configured to allow a first fluid to flow therethrough,
• wherein the second flow path is configured to allow a second fluid isolated from the first fluid to flow therethrough,
• wherein the third flow path is configured to allow a third fluid to flow therethrough,
• wherein the heat exchanger performs heat exchange between the first fluid flowing through the first flow path and the third fluid flowing through the third flow path, and between the second fluid flowing through the second flow path and the third fluid flowing through the third flow path,
• wherein the first flow path wall and the second flow path wall are formed such that the first flow path and the second flow path are three-dimensionally intertwined,
• wherein an inlet of the first flow path is configured to directly receive the first fluid and an inlet of the second flow path is configured to directly receive the second fluid, and wherein each of the first flow path wall and the second flow path wall has a gyroid structure.