Abstract: An evaporative heat exchanger includes first and second stacked plates forming a first fluid flow path between a first end and a second end. The first stacked plate defines a plane. Third and fourth stacked plates define a second fluid flow path. A fluid flow plate is positioned between the first and second stacked plates, and has a plurality of flow channels extending substantially parallel to the plane between the first end and the second end. At least one of the first and second stacked plates defines slots that form a portion of the first fluid flow path so that fluid flowing along the first fluid flow path flows along the flow channels in the first direction, then flows along at least one of the slots, then flows into adjacent flow channels and then along the adjacent flow channels in a second direction parallel to the first direction.

Abstract: A fuel supply system includes a source of oxidizer providing oxidizer at an oxidizer pressure, a source of fuel providing fuel at a fuel pressure, and a fuel pressure regulator referenced to the oxidizer pressure. The fuel pressure regulator receives the fuel from the source of fuel at the fuel pressure, and discharges the fuel at an outlet pressure that is lower than the fuel pressure and proportional to the oxidizer pressure.