Urban Air Vehicle implementation and limitations. Development of a new acoustic tool for the noise prediction

This work presents the prediction and the optimization study of noise produced by rotors of a new concept of transport: UAV (Urban Air Vehicle). This project of UAM (Urban Air Mobility) evolved in the recent years due to the overcrowding of the cities’ roads; this is a solution that at the same time brought up to light different issues and one of these, main theme of this document, is the noise pollution. However, the ability to rapidly assess the performance of these new generation of vertical lift vehicles, with sufficient fidelity, is a current weakness of this nascent industry. For this reason, the intention of this study is the prediction of the noise produced by the rotor itself, the study of minimization and optimization of the noise sources. For this purpose, is adopted an open-source suite of mixed-fidelity aerodynamics and aeroacoustics (FLOWUnsteady) simulations. This latter is able to fully characterize induced velocities across the stable region flow, where blade element momentum theory (BEMT) operates. This method is coupled with an aeroacoustics solver for tonal (FW-H code PSU WOP-WOP based on Farassat 1-A formulation) and broadband noise predictions (Brooks, Pope, and Marcolini (BPM) equations). To validate the data produced through this simulation and prediction program the thesis is divided in a computational and an experimental part. In the first part wings, body and rotating blades are modelled through a combination of panel, vortex lattice, lifting line, and blade elements. Meanwhile, the second part is the analysis of the same model elaborated by the software in an anechoic chamber, in order to validate the data. This comparison allowed to confirm the high fidelity of the computational method adopted and affirm the studied noise optimization method with the objective to guarantee the use of this new concept of transport in the classic city routine.