Abstract: A gas turbine engine has: a core flowpath sequentially through one or more fan sections, one or more compressor sections, a combustor section, and one or more turbine sections; a bypass flowpath extending through the one or more fan sections and bypassing the combustion section; a heat exchanger in the bypass flowpath placing a portion of the bypass flowpath in heat exchange relation with a second fluid flowpath; a first thermoelectric generator having a first side upstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath; and a second thermoelectric generator having a first side downstream of the heat exchanger along the bypass flowpath and a second side away from the bypass flowpath.

Abstract: A heat exchanger can comprise: a housing; a heat transfer region disposed within the housing; and an inlet manifold or an inlet conduit defined at least partially by an interior surface extending axially from a first end of the heat exchanger to an inlet defined by the heat transfer region, the inlet manifold or the inlet conduit comprising a dimple configuration disposed in the interior surface. The heat exchanger can further comprise an outlet manifold or an outlet conduit including a dimple configuration disposed on an interior surface of the outlet manifold or outlet conduit.

Abstract: A heat exchanger can comprise: a housing; a heat transfer region disposed within the housing; and an inlet manifold or an inlet conduit defined at least partially by an interior surface extending axially from a first end of the heat exchanger to an inlet defined by the heat transfer region, the inlet manifold or the inlet conduit comprising a dimple configuration disposed in the interior surface. The heat exchanger can further comprise an outlet manifold or an outlet conduit including a dimple configuration disposed on an interior surface of the outlet manifold or outlet conduit.