Current aircraft engine designs tend towards higher bypass ratio, low-speed fan designs for improved fuel burn, reduced emissions and noise. Alternative propulsion concepts include counter-rotating propfans (CRPs) which have been investigated intensively in the 1970s and 1980s and demonstrated significant reductions in fuel burn. Currently, propfans are being studied again due to their inherent noise challenge and the potential for reduced environmental impact. A newly developed, integrated noise and performance assessment methodology for advanced propfan powered aircraft configurations is introduced. The approach is based on first principles and combines a coupled aircraft and propulsion system performance analysis with 3-D unsteady, full-wheel CRP CFD computations and aero-acoustic simulations. Special emphasis is put on computing CRP interaction tones. The method is capable of dealing with parametric studies and exploring noise reduction technologies. An aircraft performance and mission analysis was first conducted on a candidate CRP powered configuration. In addition, a comparable aircraft with advanced turbofan engines was defined for performance and noise comparisons.
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