Heat exchanger

An annular heat exchanger comprising a first continuous sheet of material and a second continuous sheet of material, wherein the first and second continuous sheets of material have longitudinally extending edges,

• the first continuous sheet of material is arranged in a spiral about an axis, the first continuous sheet of material has a first surface and a second surface,
• the second continuous sheet of material is arranged in a spiral about said axis, the second continuous sheet of material has a third surface and a fourth surface,
• a first axially extending passage is defined between the first surface of the first continuous sheet of material and the third surface of the second continuous sheet of material, the first axially extending passage has a first axial end and a second axial end, the first and second axial ends of the first axially extending passage are sealed at the edges of the first and second continuous sheets of material,
• a second axially extending passage is defined between the second surface of the first continuous sheet of material and the fourth surface of the second continuous sheet of material, the second axially extending passage has axial ends, the axial ends of the second axially extending passage are open,
• at least one first radially extending passage extending through one of the first and second continuous sheets of material to supply a first fluid radially outwardly into the first axially extending passage at the first axial end of the first axially extending passage,
• at least one second radially extending passage extending through the one of the first and second continuous sheets of material to remove the first fluid radially inwardly from the first axially extending passage at the second axial end of the first axially extending passage,
• a space defined within the annular heat exchanger
• means to define at least one space around the annular heat exchanger,
• means to supply the first fluid to the space within the annular heat exchanger such that the first fluid is supplied to the at least one first radially extending passage,
• means to remove the first fluid from the space within the heat exchanger such that the first fluid is removed from the at least one second radially extending passage,
• a blanking member within the space within the annular heat exchanger to separate the inlet flow and outlet flow of the first fluid,
• and means to pressurize the interior of the at least one space around the annular heat exchanger and the interior of the space within the annular heat exchanger to apply a radial compressive load on the annular heat exchanger.