Modeling the Normal Modes and Acoustics of a Jet Engine
نویسنده
چکیده
There are at least two challenges that the jet engine noise community is currently facing. One challenge is due to existing engines that are being extended to higher power ratings without increasing the passive noise control treatment area. The second challenge comes about with the increasing trend to go to ultra-high bypass engines. This increases the importance of the fan tone noise and at the same time, due to decreased duct surface area, makes passive noise control treatment more difficult to apply.[l] These two challenges combined with increasing noise regulations from the FAA on jet engine noise have caused researchers to look into additional noise control methods besides passive noise control for decreasing engine noise. One method which is being investigated is active noise control (ANC) of fan noise from the turbofan jet engine. Fan noise is an ideal target for ANC because it is relatively low in frequency and is sinusoidal in nature.
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