Experimental Investigation of The Aeroacoustic Interaction Effects of Installed Pusher Propellers

What is it about?

The pusher propeller configuration can be more efficient aerodynamically than a tractor one. As a drawback, pusher propellers can be noisier than the tractor design, due to the non-uniform inflow coming from the wing. Investigation of noise emissions from this configuration is quite challenging, and using multiple propellers adds further complication, due to the interaction between the flow, the wing and the propellers affecting the development of the flow as well as noise generation and propagation. The ERaCLE project (invEstigation of pushing pRopeller engine Configurations trough wind tunneL Experiments) has been developed to provide an aeroacoustic characterization of a twin pusher propeller configuration installed on a wing, powered by electric motors, to better understand and minimize the noise emitted by such a promising propulsion system. The project was coordinated by IBK Innovation and involved other international partners: University of Roma Tre for the wind tunnel testing and data post processing, NHOE srl for the automation and control systems installed on the model, Eligio Re Fraschini SpA for the manufacturing, as well as the Pininfarina Wind Tunnel facility.

Featured Image

Photo by Timothy Newman on Unsplash

Photo by Timothy Newman on Unsplash

Why is it important?

Increasing concerns about environmental issues raise the need for more fuel-efficient aircrafts, drawing the attention on propellers as an alternative to turbofans. Distributed propulsion attempts to fulfil the challenging goals for aircraft environmental impact mitigation, employing an array of propulsors located across the air vehicle to deliver the vehicle thrust. Electric and hybrid distributed electric propulsion solutions thus represent an increasingly attractive option for the aviation industry, although they were scarcely investigated in terms of noise emissions.