Methods of ducted fan aircraft propulsion unit noise prediction

David Hlaváček


The UL-39 ultra-light aircraft which is being developed by the Department of Aerospace Engineering, Faculty of Mechanical Engineering, Czech Technical University in Prague, is equipped with an unconventional ducted fan propulsion unit. This paper deals with identifying noise sources of this propulsion unit and easily applicable ways of predicting its noise level. At the end, a few potential noise-suppressing design improvements are presented.

Słowa kluczowe: UL-39, ducted fan propulsion unit, rotor-stator interaction noise, rotor-alone noise, cold air jet noise, flow passage noise

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