Abstract
Optimization of the cross-sectional area distribution of a high-speed train nose is conducted for various nose lengths in order to minimize the micro-pressure wave intensity at a tunnel exit. To this end, an inviscid compressible flow solver is adopted with an axi-symmetric patched grid system. To improve the shape of the train nose, multi-step design optimization is performed using the Broyden–Fletcher–Goldfarb–Shanno (BFGS) algorithm with a response surface model. The optimization reveals that the optimal nose shapes differ for different nose lengths. For a short nose, the shape has an extremely blunt front end, and the cross-sectional area decreases in the middle section. As the nose length increases, the nose shape flattens around the middle section. These optimal shapes divide one large compression wave into two small waves by causing a strong expansion effect between the front and rear ends. As a result, through the nose shape optimization, the intensity of the micro-pressure wave is reduced by 18–27% compared to a parabolic nose, which has a minimum variation of the cross-sectional area change. The optimized distribution of the cross-sectional area can be used as a guideline for the design of three-dimensional nose shapes of high-speed trains, further improving their aerodynamic performance.
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References
Arora JS (1989) Introduction to optimum design. McGraw-Hill, New York
Auvity B, Bellenoue M (2005) Effects on an opening on pressure wave propagation in a tube. J Fluid Mech 538:269–289
Bellenoue M, Auvity B, Kageyama T (2001) Blind hood effects on the compression wave generated by a train entering a tunnel. Exp Therm Fluid Sci 25:397–407
Fujii K (1995) Unified zonal method based on the fortified solution algorithm. J Comput Phys 118(1):92–108
Hirsch C (1988) Numerical computation of internal and external flows. Wiley, New York
Iida M, Matsumura T, Nakatani K, Fukuda T, Maeda T (1997) Effective nose shape for reducing tunnel sonic boom. QR of RTRI 38(4):206–211
Kim I, Ok H (1998) A study on the aerodynamic characteristics of a high speed train entering a tunnel and frontal shape optimization. J KSAS 26(1):17–26
Ku Y-C, Yun S-H, Rho J-H, Kim K-H, Lee D-H, Kwon H-B (2008) Nose shape optimization of high-speed train for speed up in tunnel. In: Proceedings of Korean Society for railway. Hotel Inter-Burgo, Daegu, Korea
Ku Y-C, Kwak M-H, Park H-I, Lee D-H (2010) Multi-objective optimization of high-speed train nose shape using the vehicle modeling function. In: 48th AIAA aerospace sciences meeting. Orlando, USA
Kwon HB, Jang KH, Kim YS, Lee KJ, Lee DH (2001a) Nose shape optimization of high-speed train for minimization of tunnel sonic boom. JSME Int J Ser C 44(3):890–899
Kwon HB, Kim YS, Lee DH, Kim MS (2001b) Nose shape optimization of the high-speed train to reduce the aerodynamic drag and micro-pressure wave. In: Proceedings of the Korean Society of mechanical engineers, pp 373–379
Kwon HB, Kim TY, Lee DH, Kim MS (2003) Numerical simulation of unsteady compressible flows induced by a high-speed train passing through a tunnel. Proc Inst Mech Eng F J Rail Rapid Transit 217(2):111–124
Lee J, Kim J (2008) Approximate optimization of high-speed train nose shape for reducing micropressure wave. Struct Multidisc Optim 35(1):79–87
Maeda T, Matsumura T, Iida M, Nakatani K, Uchida K (1993) Effect of shape of train nose on compression wave generated by train entering tunnel. In: The international conference on speedup technology for railway and maglev vehicles. Pacific Convention Plaza, Yokohama
Myers RH, Montgomery DC (1995) Response surface methodology: process and product optimization using designed experiments. Wiley, New York
Ogawa T, Fujii K (1995) Effect of train shape on a compression wave generated by a train moving into a tunnel. In: Proceedings of Korean Society of computational fluids engineering
Ogawa T, Fujii K (1996–1997) Theoretical algorithm to design a train shape for alleviating the booming noise at a tunnel exit. J Jpn Soc Mech Eng 62(599):2679–2686
Ozawa S, Maeda T (1988) Model experiment on reduction of micro-pressure wave radiated from tunnel exit. In: JSME international symposium on scale modeling. Tokyo
Peters JL (1982) Optimizing aerodynamics to raise IC performance. Railw Gaz Int 138(10):817–819
Roe PL (1981) Approximate Riemann solvers, parameter vectors and difference scheme. J Comput Phys 43(2):357–372
Sweby PK (1985) High resolution TVD schemes using flux limiters. Lect Appl Math 22:289–309
Vanderplaats GN (1999) Numerical optimization techniques for engineering design, 3rd edn. Vanderplaats Research & Development Inc, Colorado Springs
William-Louis M, Tournier C (2005) A wave signature based method for the prediction of pressure transients in railway tunnels. J Wind Eng Ind Aerodyn 93(4):521–531
Yoon TS, Lee S, Hwang JH, Lee DH (2001) Prediction and validation on the sonic boom by a high-speed train entering a tunnel. J Sound Vib 247:195–211. doi:10.1006/jsvi.2000.3482
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This work was supported by the second stage of the Brain Korea 21 Project and the Railroad Technology Development Program funded by the Ministry of Land, Transport, and Maritime Affairs.
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Ku, YC., Rho, JH., Yun, SH. et al. Optimal cross-sectional area distribution of a high-speed train nose to minimize the tunnel micro-pressure wave. Struct Multidisc Optim 42, 965–976 (2010). https://doi.org/10.1007/s00158-010-0550-6
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DOI: https://doi.org/10.1007/s00158-010-0550-6