Investigation of Installation Effects of the Volocopter-2X Rod Structure

The installation effects of the Volocopter-2X beam structures are studied by performing high-fidelity simulations of singleand three-rotor configurations in hover. To verify the installation effects, the studied cases are compared with simulations without an airframe. In addition, the noise emission of the configurations is simulated using a Ffowcs Williams-Hawkings-based computational aeroacoustic code. Scattering effects are also included by using a boundary element method code as well as a permeable integration surface surrounding the entire configuration. The rotors are simulated at identical rotational speeds and in their respective mounting positions. An additional setup with individual rotational speeds is simulated for the three-rotor configuration. The installation mainly affects the rotor wake, thrust, and pressure fluctuations on the rotor, while the integral aerodynamic quantities remain almost unchanged. This results in additional oscillations in the acoustic pressure signal. Overall, the installation increases the overall sound pressure level by about 1.5 dB. However, it has a larger effect on the 3rd ‐ 20th harmonics. The simulation data were compared with measurements performed by Volocopter and showed good agreement. For the three-rotor configurations, the rotor???rotor interactions were found to be dominant for the aerodynamic and acoustic performance, while the installation effects only locally affected the noise emission by 3‐4 dB.