Bifurcated exhaust duct for hybrid aircraft powerplant

An aircraft system, comprising:

• a compressor section;
• a combustor section;
• a turbine section;
• an exhaust duct including an upstream duct section, a plurality of intermediate duct sections and a downstream duct section, a first of the plurality of intermediate duct sections fluidly discrete from a second of the plurality of intermediate duct sections, and the plurality of intermediate duct sections fluidly coupled in parallel between the upstream duct section and the downstream duct section;
• and
• a flowpath extending sequentially longitudinally through the compressor section, the combustor section, the turbine section, the upstream duct section, the plurality of intermediate duct sections and the downstream duct section from an inlet into the flowpath to an outlet from the flowpath;
• wherein each of the plurality of intermediate duct sections has an intermediate section cross-sectional flow area at a midpoint longitudinally between the upstream duct section and the downstream duct section;
• and
• wherein the downstream duct section has a downstream section cross-sectional flow area that is within five percent of a sum of the intermediate section cross-sectional flow area of each of the plurality of intermediate duct sections.

An aircraft system, comprising:

• a compressor section;
• a combustor section;
• a turbine section;
• an exhaust duct including an upstream duct section, a plurality of intermediate duct sections and a downstream duct section, a first of the plurality of intermediate duct sections fluidly discrete from a second of the plurality of intermediate duct sections, and the plurality of intermediate duct sections fluidly coupled in parallel between the upstream duct section and the downstream duct section;
• and
• a flowpath extending sequentially longitudinally through the compressor section, the combustor section, the turbine section, the upstream duct section, the plurality of intermediate duct sections and the downstream duct section from an inlet into the flowpath to an outlet from the flowpath;
• wherein the upstream duct section has an upstream section cross-sectional flow area;
• and
• wherein the downstream duct section has a downstream section cross-sectional flow area that is within five percent of the upstream section cross-sectional flow area.