Spiral heat exchanger with monolithic phase change material chamber

A method of assembling a heat exchanger, the method comprising:

• forming a monolithic main body extending along an axis from a first end to a second end, the main body including a plurality of flow channels configured to channel a first material from an inlet to an outlet, each of the plurality of flow channels traversing a spiral flow path from the inlet at a center of the main body to the outlet at an exterior surface of the main body, wherein the plurality of flow paths are aligned along the axis, and the main body including a plurality of passages configured to hold a second material, each of the plurality of passages extending along the axis from the first end to the second end, wherein a first end and a second end, opposite the first end, of each of the passages is defined by the spiral flow path of the plurality of flow channels;
• fastening a first cover at the first end of the main body;
• and
• fastening a second cover at the second end of the main body.