Optimising the X3R Reflected Shock Tunnel Free-Piston Driver for Long Duration Test Times

  • S. StennettEmail author
  • D. E. Gildfind
  • P. A. Jacobs
Conference paper


The X3R free-piston reflected shock tunnel is an alternate operating mode of the existing X3 expansion tube facility at The University of Queensland, which has been funded by Australia’s Defence Science and Technology Group to provide ground testing capability for the full-scale HIFiRE 8 scramjet engine. Given X3R’s origin as an expansion tube, its relatively short driver compared to its shock tube introduces unique design constraints during its condition development process, requiring careful tuning of the free piston to maximise the available test time. This paper details the ideal and equilibrium gas shock interactions required to provide the candidate Mach 7, 50 kPa dynamic pressure nozzle exit flow, the trends that arise as part of the driver composition selection and optimisation process, the free-piston tuning analysis used to maximise X3R’s driver supply time given its short driver, and the modelling and analysis of facility operation using one-dimensional computational techniques.



This research is supported by the Australian Government’s Research Training Program (RTP) and the Cooperative Research Centre for Space Environment Management (SERC Limited) through the Australian Government’s Cooperative Research Centre Programme.


  1. 1.
    H. Alesi et al., A concept for the HIFiRE 8 flight test, in 22nd ESA Symposium on European Rocket and Balloon Programmes and Related Research, 2015Google Scholar
  2. 2.
    R. Morgan, D. Gildfind, X3 reflected shock tunnel for extended flow duration, in The 2014 Asia-Pacific International Symposium on Aerospace Technology, 2014Google Scholar
  3. 3.
    A. Dann et al., Upgrade of the X3 super-orbital expansion tube, in 18th Australasian Fluid Mechanics Conference, 2012Google Scholar
  4. 4.
    J. Anderson, Modern Compressible Flow with Historical Perspective (McGraw-Hill Education, Boston, 2003)Google Scholar
  5. 5.
    P. Jacobs et al., Estimation of High-Enthalpy Flow Conditions for Simple Shock and Expansion Processes Using the ESTCj Program and Library, UQ Mechanical Engineering Report 2011/02, 2011Google Scholar
  6. 6.
    C. James et al., Designing and simulating high enthalpy expansion tube conditions, in The 2013 Asia-Pacific International Symposium on Aerospace Technology, 2013Google Scholar
  7. 7.
    H. Hornung, The Piston Motion in a Free-Piston Driver for Shock Tubes and Tunnels, GALCIT Report FM 88-1, 1988Google Scholar
  8. 8.
    K. Itoh et al., Improvement of a free piston driver for a high-enthalpy shock tunnel. Shock Waves 8(4), 215–233 (1998)CrossRefGoogle Scholar
  9. 9.
    R. Stalker, A study of the free-piston shock tunnel. AIAA J. 5(12), 2160–2165 (1967)CrossRefGoogle Scholar
  10. 10.
    D. Gildfind et al., Free-piston driver performance characterisation using experimental shock speeds through helium. Shock Waves 25(2), 169–176 (2015)CrossRefGoogle Scholar
  11. 11.
    W. Chan et al., Flowpath Design of an Axisymmetric Mach 7.0 Nozzle for T4, UQ Mechanical Engineering Report 2013/02, 2013Google Scholar
  12. 12.
    P. Jacobs, Using l_script to Define L1d Simulations, UQ Mechanical Engineering Report 2005/09, 2005Google Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  1. 1.The Centre for HypersonicsThe University of QueenslandSt. LuciaAustralia

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