Gas turbine engines may be employed to power various devices. For example, a gas turbine engine may be employed to supply power to a mobile platform, such as an aircraft. In certain examples, the gas turbine engine is an auxiliary power unit, which can supply power to run various electrical systems of the aircraft. Certain electrical systems are supplied by a generator, through a gearbox driven by the gas turbine engine. As needs for power increase, heat output by the generator into a compartment of the gas turbine engine may increase and a temperature of the lubricating fluid associated with the gearbox may also increase. Moreover, in certain instances, the auxiliary power unit can run while the aircraft is on the ground, prior to taxiing for flight. In these instances, noise generated by the auxiliary power unit may be undesirable to one or more passengers or crew onboard the aircraft and service personnel outside.
Accordingly, it is desirable to provide improved exhaust systems and methods for a gas turbine engine, such as an auxiliary power unit, which provides for increased cooling of a compartment of the gas turbine engine, increased cooling of a lubrication fluid, and that attenuates sound generated by the operation of the gas turbine engine. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.