Effect of the cavity edge topology on the aerodynamic noise of a pantograph in high-speed train

Abstract

This research investigates the aerodynamic flow behavior and noise contribution of various cavity configurations designed to reduce aerodynamic noise in a simplified DSA 350 SEK pantograph model, scaled to 1/10. The cavities are classified into dual-shape and single-shape designs, with four distinct models (concave–convex, convex–concave, convex, and concave) analyzed in three sizes. A base cavity with a sloped edge at θ = 80° serves as a reference for comparison. Computational fluid dynamics (CFD) simulations are performed to evaluate flow characteristics, followed by the Ffowcs Williams and Hawkings (FW–H) aeroacoustic analogy is applied to estimate far-field sound pressure levels (SPLs). The results demonstrate that the convex-edged cavity improves aerodynamic performance by reducing the root-mean-square (RMS) drag and lift coefficients from 0.026 to 0.023 and from −0.06 to −0.038, respectively, and lowering the mean drag and lift coefficients from 0.23 to 0.18 and from −1.3 to −0.85, relative to the base cavity, thereby mitigating both steady and unsteady aerodynamic forces. Noise predictions, obtained from receivers positioned 2.5 m away in the scaled model at a train speed of 300 km/h, show reductions in noise levels from 81.9 to 77.3 dB at the top receiver and from 68.4 to 63.1 dB at the side receiver. Incorporating the pantograph into the optimal and base cavity designs reveals further aerodynamic improvements, with the optimal cavity reducing the pantograph’s aerodynamic noise by 2.7 dB(A) in total sound power. Sound pressure levels decrease by 2.3 dB(A) at the top receiver and 1.8 dB(A) at the side receiver compared to the base cavity.

Keywords

Aerodynamic noise control / Pantograph / Cavity / High-speed train / Computational fluid dynamics (CFD) / Ffowcs Williams–Hawkings acoustic analogy (FW–H) / Improved Delayed Detached Eddy Simulation (IDDES)

References

[1] Dalla Chiara B, De Franco D, Coviello N, et al.. Comparative specific energy consumption between air transport and high-speed rail transport: a practical assessment. Transp Res Part D: Transp Environ, 2017, 52: 227-243

[2] Lindstad E, Lagemann B, Rialland A, et al.. Reduction of maritime GHG emissions and the potential role of E-fuels. Transp Res Part D Transp Environ, 2021, 101 103075

[3] Thompson DJ, Latorre Iglesias E, Liu X, et al.. Recent developments in the prediction and control of aerodynamic noise from high-speed trains. Int J Rail Transp, 2015, 3(3): 119-150

[4] Talotte C. Aerodynamic noise: a critical survey. J Sound Vib, 2000, 231(3): 549-562

[5] Mellet C, Létourneaux F, Poisson F, et al.. High speed train noise emission: latest investigation of the aerodynamic/rolling noise contribution. J Sound Vib, 2006, 293(3/4/5): 535-546

[6] Noh H-M. Noise-source identification of a high-speed train by noise source level analysis. Proc Inst Mech Eng Part F J Rail Rapid Transit, 2017, 231(6): 717-728

[7] Noh H-M, Choi S, Hong S, et al.. Investigation of noise sources in high-speed trains. Proc Inst Mech Eng Part F J Rail Rapid Transit, 2014, 228(3): 307-322

[8] Talotte C, Gautier P-E, Thompson DJ, et al.. Identification, modelling and reduction potential of railway noise sources: a critical survey. J Sound Vib, 2003, 267(3): 447-468

[9] Lölgen T. Wind tunnel noise measurements on full-scale pantograph models. Acoust Soc Am J, 1999, 105(2): 1136

[10] Grosche FR, Meier GEA. Research at DLR Göttingen on bluff body aerodynamics, drag reduction by wake ventilation and active flow control. J Wind Eng Ind Aerodyn, 2001, 89(14/151201-1218

[11] Tan XM, Xie PP, Yang ZG, et al.. Adaptability of turbulence models for pantograph aerodynamic noise simulation. Shock Vib, 2019, 2019(1 6405809

[12] Jackson FF, Mishra R, Rebelo JM, et al.. Modelling dynamic pantograph loads with combined numerical analysis. Railw Eng Sci, 2024, 32(1): 81-94

[13] Zhang YD, Han L, Li M, et al.. Reduction of aerodynamic noise of high-speed train pantograph. J Mech Eng, 2017, 53(6): 94-101

[14] Ikeda M, Suzuki M, Yoshida K. Study on optimization of panhead shape possessing low noise and stable aerodynamic characteristics. QR RTRI, 2006, 47(2): 72-77

[15] Li T, Dai Z, Zhang W. Effect of RANS model on the aerodynamic characteristics of a train in crosswinds using DDES. Comput Model Eng Sci, 2020, 122(2): 555-570

[16] Dai Z, Li T, Deng J, et al.. Effect of the strip spacing on the aerodynamic performance of a high-speed double-strip pantograph. Veh Syst Dyn, 2022, 60(10): 3358-3374

[17] Lee Y, Rho J, Kim KH, et al.. Experimental studies on the aerodynamic characteristics of a pantograph suitable for a high-speed train. Proc Inst Mech Eng Part F J Rail Rapid Transit, 2015, 229(2): 136-149

[18] Guo J, Tan XM, Yang ZG, et al.. Aeroacoustic optimization design of the middle and upper part of pantograph. Appl Sci, 2022, 12(17): 8704

[19] Plentovich EB, Stallings RL, Tracy MB (1993) Experimental cavity pressure measurements at subsonic and transonic speeds. Technical Paper No. TP-3358, NASA Langley Research Center, Hampton, VA

[20] Ng YT. Characterising low-speed, transitional cavity flow. Aeronaut J (1968), 2012, 116(11851185-1199

[21] Noger C, Patrat JC, Peube J, et al.. Aeroacoustical study of the tgv pantograph recess. J Sound Vib, 2000, 231(3): 563-575

[22] Tan X, Liu H, Yang Z, et al.. Comparative study of aeroacoustic performance of 1/8 and 1/1 pantographs coupled with cavity. Railw Eng Sci, 2024, 32(4): 551-572

[23] Kim H, Hu Z, Thompson D. Numerical investigation of the effect of cavity flow on high speed train pantograph aerodynamic noise. J Wind Eng Ind Aerodyn, 2020, 201 104159

[24] Thompson D, Zhao D, Squicciarini G. Simplified prediction models for acoustic installation effects of train-mounted equipment. Railw Eng Sci, 2024, 32(2): 125-143

[25] Kim H, Hu Z, Thompson D. Effect of cavity flow control on high-speed train pantograph and roof aerodynamic noise. Railw Eng Sci, 2020, 28(1): 54-74

[26] Dong T, Li T. Numerical comparison in aerodynamic drag and noise of high-speed pantographs with or without platform sinking. Appl Sci, 2023, 13(10 6213

[27] Qin D, Li T, Zhou N, et al.. Aerodynamic drag and noise reduction of a pantograph of high-speed trains with a novel cavity structure. Phys Fluids, 2024, 36(2 027108

[28] Yuan CY, Li MQ. Multi-objective optimization for the aerodynamic noise of the high-speed train in the near and far field based on the improved NSGA-II algorithm. J Vibroeng, 2017, 19(6): 4759-4782

[29] Zhang Y, Zhang J, Li T, et al.. Investigation of the aeroacoustic behavior and aerodynamic noise of a high-speed train pantograph. Sci China Technol Sci, 2017, 60(4): 561-575

[30] Lu WT, Wang Y, Zhang CQ. Research on the distribution of aerodynamic noises of high-speed trains. J Vibroeng, 2017, 19(2): 1438-1452

[31] Wang YH, Wang JT, Fu LQ. Numerical computation of aerodynamic noises of the high speed train with considering pantographs. J Vibroeng, 2016, 18(8): 5588-5604

[32] Yang HX, Liu DM. Numerical study on the aerodynamic noise characteristics of CRH2 high-speed trains. J Vibroeng, 2017, 19(5): 3953-3967

[33] Li T, Qin D, Zhang W, et al.. Study on the aerodynamic noise characteristics of high-speed pantographs with different strip spacings. J Wind Eng Ind Aerodyn, 2020, 202 104191

[34] Cui YF, Tian C, Zhao ZY. Research on the radiation characteristics of aerodynamic noises in the connection position of high-speed trains. J Vibroeng, 2017, 19(4): 3099-3112

[35] Li T, Hemida H, Zhang J, et al.. Comparisons of shear stress transport and detached eddy simulations of the flow around trains. J Fluids Eng, 2018, 140(11 111108

[36] Light Hill MJ. On sound generated aerodynamically I. General theory. Proc R Soc Lond A, 1952, 211(1107): 564-587

[37] Ffowcs Williams JE, Hawkings DL. Sound generation by turbulence and surfaces in arbitrary motion. Philos Trans R Soc Lond Ser A, 1969, 264(1151): 321-342

[38] Farassat F (2007) Derivation of formulations 1 and 1A of Farassat. NASA Technical Memorandum 2007–214853. NASA, Washington, DC

RIGHTS & PERMISSIONS

The Author(s)

Just Accepted

This article has successfully passed peer review and final editorial review, and will soon enter typesetting, proofreading and other publishing processes. The currently displayed version is the accepted final manuscript. The officially published version will be updated with format, DOI and citation information upon launch. We recommend that you pay attention to subsequent journal notifications and preferentially cite the officially published version. Thank you for your support and cooperation.