Numerical Investigation on the Aerodynamic Noise Generated by a Simplified Double-Strip Pantograph
نویسندگان
چکیده
In order to understand the mechanism by which a pantograph can generate aerodynamic noise and grasp its far-field characteristics, simplified double-strip is analyzed numerically. Firstly, unsteady flow field around simulated in frame of large eddy simulation (LES) technique. Then location main source determined using surface fluctuating pressure data vortex structures are means Q-criterion. Based on this, relationship between wake intensity sound discussed. Finally, calculated Ffowcs Williams-Hawkings (FW-H) equation, contribution each component total frequency spectrum characteristics analyzed. The results show that where shedding or interaction with upstream components occurs, fluctuation more intense, resulting strong dipole sources. energy mainly concentrated band below 1500 Hz. peaks generated base frame, balance arm rear strip, also contributors noise.
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ژورنال
عنوان ژورنال: Fluid dynamics & materials processing
سال: 2022
ISSN: ['1555-2578', '1555-256X']
DOI: https://doi.org/10.32604/fdmp.2022.017508