Analysis and modelling of unsteady shock train motions.

*(English)*Zbl 1421.76151Summary: The characteristics and mechanism for unsteady shock train motions were experimentally studied in a constant-area rectangular duct. High-speed Schlieren techniques and high-frequency pressure measurements were utilized in this research. The results show that the shock train undergoes periodical motions in response to downstream periodical excitations. The mechanism for unsteady shock train motions is that the shock train keeps changing its moving speed to change the relative Mach number ahead of shock train to match the varying back-pressure condition. It can be found that the unsteady shock train motion can be predicted well with a theoretical model, which is based on this mechanism. A correlation between the amplitude of shock train motions and some flow parameters was illustrated using an analytical equation, which was confirmed by the experimental results.

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[1] | Bruce, P. J. K.; Babinsky, H., Unsteady shock wave dynamics, J. Fluid Mech., 603, 463-473, (2008) · Zbl 1151.76311 |

[2] | Bur, R.; Benay, R.; Galli, A., Experimental and numerical study of forced shock-wave oscillations in a transonic channel, Aerosp. Sci. Technol., 10, 1, 265-278, (2006) |

[3] | Culick, F. E. C.; Rogers, T., The response of normal shocks in diffusers, AIAA J., 21, 1, 1382-1390, (1983) · Zbl 0522.76071 |

[4] | Gnani, F.; Zare-Behtash, H.; Kontis, K., Pseudo-shock waves and their interactions in high-speed intakes, Prog. Aerosp. Sci., 1, 1-21, (2016) |

[5] | Hu, J.; Chang, J. T.; Qin, B.; Wang, L., Scramjet isolator shock-train leading-edge position modeling based on equilibrium manifold, J. Aerosp. Eng., 64, 4, 1-8, (2013) |

[6] | Hutzel, J. R., Decker, D. D., Cobb, R. G., King, P. I. & Veth, M. J.2011 Scramjet isolator shock train location techniques. AIAA Paper 2011-402. |

[7] | Jong, Y. O.; Fuhua, M.; Shihyang, H., Interactions between shock and acoustic waves in a supersonic inlet diffuser, J. Propul. Power, 21, 3, 486-495, (2005) |

[8] | Klomparens, R. L., Driscoll, J. F. & Gamba, M.2015 Unsteadiness characteristics and pressure distribution of an oblique shock train. AIAA Paper 2015-1519. |

[9] | Klomparens, R. L., Driscoll, J. F. & Gamba, M.2016 Response of a shock train to downstream back pressure forcing. AIAA Paper 2016-0078. |

[10] | Lanurence, S. J.; Schramm, J. M.; Hannemann, K., Transient fluid-combustion phenomena in a model scramjet, J. Fluid Mech., 722, 85-120, (2013) · Zbl 1287.76235 |

[11] | Le, D. B.; Goyne, C. P.; Krauss, R. H., Shock train leading-edge detection in a dual-mode scramjet, J. Propul. Power, 24, 5, 1035-1041, (2008) |

[12] | Matsuo, K.; Miyazato, Y.; Kim, H. D., Shock train and pseudo-shock phenomena in internal gas flows, Prog. Aerosp. Sci., 35, 33-100, (1999) |

[13] | Morgan, B.; Duraisamy, K.; Lele, S. K., Large-eddy simulations of a normal shock train in a constant-area isolator, AIAA J., 52, 3, 539-558, (2014) |

[14] | Su, W. Y.; Ji, Y. X.; Chen, Y., Effects of dynamic backpressure on pseudoshock oscillations in scramjet inlet-isolator, J. Propul. Power, 32, 2, 1-13, (2016) |

[15] | Sugiyama, H., Tsujiguchi, Y. & Honma, T.2008 Structure and oscillation phenomena of pseudo-shock waves in a straight square duct at Mach 2 and 4. AIAA Paper 2008-2646. |

[16] | Sullins, G.1992 Experimental results of shock trains in rectangular ducts. AIAA Paper 1992-5103. |

[17] | Waltrup, P. J.; Billig, F. S., Structure of shock waves in cylindrical ducts, AIAA J., 11, 10, 1404-1408, (1973) |

[18] | Weiss, A.; Grzona, A.; Oliver, H., Behavior of shock trains in a diverging duct, Exp. Fluids, 49, 1, 355-365, (2010) |

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