Vol.16, No.1, 2020, pp.21-30, doi:10.32604/fdmp.2020.07658
OPEN ACCESS
RESEARCH ARTICLE
A Study on the Reduction of the Aerodynamic Drag and Noise Generated By the Roof Air Conditioner of High-Speed Trains
  • Jiali Liu1, Mengge Yu2, *, Dawei Chen1, Zhigang Yang3
1 CRRC Qingdao Sifang Co., Ltd., Qingdao, 266111, China.
2 College of Mechanical and Electronic Engineering, Qingdao University, Qingdao, 266071, China.
3 School of Traffic & Transportation Engineering, Central South University, Changsha, 410075, China.
* Corresponding Author: Mengge Yu. Email: yumengge0627@163.com.
(This article belongs to this Special Issue: Train Aerodynamics)
Received 07 June 2019; Accepted 15 August 2019; Issue published 01 February 2020
Abstract
In order to investigate how the aerodynamic drag and noise produced by the roof air conditioner of a high-speed train can be reduced, the related unsteady flow in the near-field was computed using the method of large eddy simulation. In this way, the aerodynamic source for noise generation has initially been determined. Then, the far-field aerodynamic noise has been computed in the framework of the Lighthill’s acoustics analogy theory. The propulsion height and flow-guide angle of the roof air conditioner were set as the design variables. According to the computational results, a lower propulsion height or flow-guide angle is beneficial in terms of aerodynamic drag and noise mitigation. However, compared to the design scheme with propulsion height of 0mm, the aerodynamic drag coefficient of the configuration with propulsion height of 190mm and flow-guide angle of 30° is slightly larger, while the aerodynamic noise is obviously reduced. Thus, from the viewpoint of the aerodynamic drag and noise, the design scheme with propulsion height of 190 mm and flow-guide angle of 30° is the optimal configuration in the range of conditions examined in the present work.
Keywords
Aerodynamic drag, aerodynamic noise, roof air conditioner, large eddy simulation, acoustics analogy theory.
Cite This Article
Liu, J., Yu, M., Chen, D., Yang, Z. (2020). A Study on the Reduction of the Aerodynamic Drag and Noise Generated By the Roof Air Conditioner of High-Speed Trains. FDMP-Fluid Dynamics & Materials Processing, 16(1), 21–30.