In Aircraft
Plug nozzles are used in aircraft typically with jet engines both because of the annular shape of the turbine exhaust and for their altitude compensating characteristics. For high speed aircraft, translating the plug or external cowl provides a means of area control with relatively simple actuation. Plug nozzles have been shown to provide noise reduction compared to traditional convergent-divergent nozzles. Weight and cooling are typical concerns with aircraft plug nozzles.
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