Evaporator system within an inner fixed structure of an aircraft propulsion system

A steam generation system for an aircraft propulsion system comprising:

• an exhaust duct comprising a central portion and at least one radial portion defining a flow path for an exhaust gas flow;
• a condenser assembly where water is condensed from the exhaust gas flow received through the exhaust duct;
• and
• an evaporator system where heat from the exhaust gas flow is used to transform water from the condenser assembly into a steam flow for communication to a core engine flow path, the evaporator system comprising a first stage separate from a second stage disposed within the exhaust duct.

A method of operating an aircraft propulsion system comprising:

• generating an exhaust gas flow with a core engine comprising a compressor, combustor, and turbine section;
• coupling a propulsor to a power turbine configured to be driven by expansion of the exhaust gas flow about a propulsor axis by the core engine;
• condensing water in condenser assembly;
• heating water from the condenser assembly in a first stage of an evaporator system with heat from the exhaust gas flow that is routed through a portion of an exhaust duct supported within an inner fixed structure;
• further heating a flow of heated water from the first stage of the evaporator system in a separate second stage of the evaporator assembly to generate a steam flow, wherein the second stage receives the exhaust gas flow before the first stage;
• and
• communicating the generated steam flow to the core engine.