Installed Propeller Design for Efficient, Low-Noise Operation

GE is invested in noise prediction capabilities and reduction technologies across a broad range of applications from aircraft engines (jets, turbofans, and turboprops/unducted fans) to wind turbines. Advancing the state-of-the-art in low-noise solutions without compromising system performance is critical in alleviating the detrimental effects of noise on communities surrounding airports as well as the cabin noise experienced by passengers, or the disruption of quiet, rural soundscapes as we aim to provide renewable energy sources via wind farms.

How applicable could this work be in benefiting applications beyond GE’s currently markets? We believe there is a broad range of applications that exhibit fundamental similarities in the sources of aeroacoustic noise for which our technologies could have an impact.  Our noise reduction solutions start with cutting-edge computational aeroacoustics (CAA) tools, coupled with our expertise in modifying the aeroacoustic design features of the noise generating system, that now allow us to simultaneously optimize for aero efficiency and noise. This enables us to bring about improvements in similar ways as Computational Fluid Dynamics (CFD) tools enabled engine aerodynamic performance improvements over recent decades through optimizing 3D turbomachinery blading. 

Furthermore, understanding of the aeroacoustics for a propulsion system in the context of the installed system at a full vehicle level is key to developing an understanding of the relative importance of several noise sources and effects contributing simultaneously.  As such, GE has invested in system-level simulations enabled by the availability of our high-performance computing facility, to allow us to evaluate designs in an installed context during the development of noise reduction concepts for a particular application.  As fans have trended larger in size to enable propulsive efficiency improvements associated with higher bypass ratios for commercial fans, or increasingly complex vehicle integration configurations are employed for embedded fans in aviation propulsion systems for the military, inflow distortion effects are increasingly important and challenging to predict, manage, and mitigate. Beyond aeroacoustic sound, this affects aerodynamic performance, operability and aeromechanics as well which must be factored in during the development of effective new solutions for these complex installations and systems.  Developing improved prediction capability and innovative solutions for installed fan and propeller distortion effects is a continuing focus area for GE.