Plate and Frame Heat Exchangers with Variable Chamber Sizes

A heat exchanger comprising:

• a chamber comprising a plurality of fluid inlets and a plurality of fluid outlets;
• and
• one or more plates inside the chamber, the one or more plates being parallel and defining fluid plenums between each of the one or more plates, the fluid plenums defining a fluid flow path, wherein each of the fluid plenums comprise one of the plurality of fluid inlets, one of the plurality of fluid outlets, a fluid path between at least two of the fluid plenums, or a combination thereof,
• wherein the one or more plates being movably mounted between guides perpendicular to a plane of the one or more plates, and
• wherein the one or more plates move along the guides, wherein the one or more plates move along the guides due to changes in pressure in the fluid plenums, application of an external force to the one or more plates, or a combination thereof.