Numerical comparisons of the aerodynamic performances of wind-tunnel train models with different inter-carriage gap spacings under crosswind. Issue 214 (July 2021)

• Record Type: Journal Article
• Authors: Xia, Yutao; Liu, Tanghong; Li, Wenhui; Dong, Xiao; Chen, Zhengwei; Guo, Zijian
• Is Part Of: Journal of wind engineering and industrial aerodynamics. Issue 214(2021)
• Publication Date: 2021-07
• Subjects: High-speed train -- Crosswind -- Wind tunnel test -- Inter-carriage gap -- Aerodynamic performances; Wind-pressure -- Periodicals; Buildings -- Aerodynamics -- Periodicals; Pression du vent -- Périodiques; Constructions -- Aérodynamique -- Périodiques; Buildings -- Aerodynamics; Wind-pressure; Periodicals
• DOI: 10.1016/j.jweia.2021.104680
• Languages: English
• ISSNs: 0167-6105

Abstract

Abstract: Reasonable gap spacings between adjacent train vehicle models are of great significance for the data accuracy during a wind tunnel test. In this research, crosswind flows around 1/8th-scale high-speed train models with inter-carriage gap spacings of 0, 5, 8, 10, and 20 mm are studied using improved delayed detached eddy simulation (IDDES) with the SST (shear-stress transport) k-omega model. The numerical methodology is first validated against the wind tunnel experiment data. Then, the effects of gap spacings on aerodynamic loads and the flow field around the train are investigated. The results indicate that the side force of the tail car significantly increases with the gap spacing, in which the maximum difference occurs at 20 mm compared with the zero gap spacing, whereas the difference in the drag decreases. When the gap spacing is greater than 10 mm, the time-averaged pressure distribution, flow pattern and transient flow structures around the inter-carriage gap regions observe a significant difference from other gap spacings. Considering the overall aerodynamic effects induced by gap spacings and the practical handleability during a wind tunnel test, a gap spacing between 5 mm and 10 mm is therefore recommended for adjacent train vehicles with a 1/8th scale. Highlights: Time-averaged quantities of train vehicle models with different gap spacings were compared. Flow patterns and structures around different gap spacings were investigated. PSD of aerodynamic loads on train vehicles with different gap spacings was analyzed. Reasonable gap spacings between adjacent train vehicle models were recommended.