Low Frequency Aero-vibro-acoustic Mechanisms in Vehicles
Aerodynamically produced sound pressure fluctuations in cavities with flexible walls are a serious issue in a variety of fields, including submarines, aircraft, and vehicles. In the research presented here, we focus on the mechanisms that occur in automobiles (i.e., at moderate Mach numbers). A viable description of the vibro-acoustic system as well as a numerical simulation of the transient aerodynamic flow is required for the precise calculation of interior noise.
The objective is to establish an experimentally validated method for the prediction of flow-induced noise in the passenger compartment using a generic body developed as part of the project.
A hybrid vibro-acoustic approach based on experimental and numerical structural and acoustic modes was developed. The approach is particular in that it allows to couple experimental structural data with an acoustic Finite Element model on behalf of non-conforming grids. The hybrid vibro-acoustic model was excited by the spatio-temporal pressure distribution obtained via Lattice-Boltzmann based flow simulation to predict the interior sound pressure spectrum. The results compare well with experimental wind channel measurements.
Engelmann, Rafael, Christoph Gabriel, Stefan Schoder, and Manfred Kaltenbacher. "A Generic Testbody for Low-Frequency Aeroacoustic Buffeting, opens an external URL in a new window." SAE Technical Papers 2020 (2020).
Engelmann, Rafael, Christoph Gabriel, Florian Toth, and Manfred Kaltenbacher. "Assessing Low Frequency Flow Noise Based on an Experimentally Validated Modal Substructuring Strategy Featuring Non-Conforming Grids, opens an external URL in a new window". No. 2022-01-0939. SAE Technical Paper, 2022.
Engelmann, Rafael, Florian Toth, Christoph Gabriel, and Manfred Kaltenbacher. "An approach for modal coupling based on experimental and computed modes using non-conforming grids, opens an external URL in a new window." Journal of Sound and Vibration (2022): 117041.
- October 2018 - June 2022