Browse Publications Technical Papers 2020-01-5038
2020-03-10

High-Fidelity Modeling and Prediction of Hood Buffeting of Trailing Automobiles 2020-01-5038

The importance of fluid-structure interaction (FSI) is of increasing concern in automotive design criteria as automobile hoods become lighter and thinner. This work focuses on computational simulation and analysis of automobile hoods under unsteady aerodynamic loads encountered at typical highway conditions while trailing another vehicle. These driving conditions can cause significant hood vibrations due to the unsteady loads caused by the vortex shedding from the leading vehicle. The study is carried out using coupled computational fluid dynamics (CFD) and computational structural dynamics (CSD) codes. The main goal of this work is to characterize the importance of fluid modeling fidelity to hood buffeting response by comparing fluid and structural responses using both Reynolds-Averaged Navier-Stokes (RANS) and detached eddy simulation (DES) approaches. Results are presented for a sedan trailing another sedan. Comparisons between RANS and DES emphasize the importance of turbulence modeling fidelity in order to capture the unsteadiness of the flow and the vibration response of the hood. These comparisons include analysis of the lift forces, pressure loads on the hood, power spectral density (PSD) analysis of the flow in the region between the two vehicles, and displacement at discrete points on the hood. As expected, DES predicts higher frequency content and significantly higher turbulence levels than RANS. The hood response is found to be sensitive to these characteristics. The increased levels of turbulence result in up to 40-60% higher maximum peak-to-peak deformation and the excitation of a torsional mode of the trailing vehicle hood.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 16% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

A CFD Simulation Approach for Optimizing Front Air-Dam to Improve Aerodynamic Drag of a Vehicle

2020-28-0361

View Details

JOURNAL ARTICLE

CFD-based Modelling of Flow Conditions Capable of Inducing Hood Flutter

2010-01-1011

View Details

TECHNICAL PAPER

Effects of Rear Slant Angles on the Flow Characteristics of the Ahmed Body by IDDES Simulations

2018-01-0720

View Details

X