a body extending in a plane, the body having a first surface and a second surface parallel to and spaced from the first surface, wherein an axis that extends through said body is substantially perpendicular to said plane;

an inlet extending into said body, and an outlet extending out of said body;

a first aperture and a second aperture each extending completely through said body along said axis;

the body consisting of one channel extending between said inlet and said outlet of said body, said channel comprising:

a first segment extending between said inlet and a midpoint between said inlet and said outlet, said first segment having at least one turn about said axis; and

a second segment extending between said midpoint and said outlet, said second segment having at least one turn about said axis, wherein at least a part of said first segment and at least a part of said second segment are interleaved to provide a more uniform composition of said fluid at a surface of said body,

wherein a fuel comprising a combination of methane and water flows through the channel,

wherein said first aperture and said second aperture are each unconnected to said channel, and

wherein said channel along an entire length of said channel extends completely through said body along said axis and from the first surface to the second surface when viewed in cross-section.