an instrumentality invented for a particular purpose

a special purpose counter-flow energy recovery heat exchanger positioned within the supply and exhaust air streams of an air handling system, or in the exhaust gases of an industrial process, in order to recover the waste heat.

a type of heat exchanger where heat from the hot fluid is intermittently stored in a thermal storage medium before it is transferred to the cold fluid.

a heat exchanger used to convert water into steam from heat produced in a nuclear reactor core.

an energy recovery heat exchanger that recovers heat from a hot gas stream.

a heat exchanger which converts steam from its gaseous to its liquid state at a pressure below atmospheric pressure.