Spectral measurements of hypervelocity flow in an expansion tunnel
- 43 Downloads
Atmospheric reentry vehicles and planetary probes fly through the atmosphere at hypervelocity speed. At such speed, there is a significant proportion of heat load to the vehicle surface due to radiative heating. Accurate prediction needs a good knowledge of the radiation spectrum properties. In this paper, a high-speed camera and spectrograph coupled to an intensified charge-coupled device have been implemented to investigate the radiation flow over a semi-cylinder model. The experiments were carried out in the JF16 expansion tunnel with secondary shock velocity of 7.9 km·s−1. Results show that the emission spectrum comprises several atomic lines and molecular band systems. We give detailed data of the radiation spectrum, shock shape, shock detached distance and radiation intensity varying with space and wavelength. This valuable experimental dataset will be helpful to validate computational fluid dynamics codes and radiation models, which equates to increased prediction accuracy of radiation heating. Also, some suggestions for spectral measurement in hypervelocity flow field were list in the end.
KeywordsSpectral measurement Hypervelocity flow Radiation Expansion tunnel
This work was supported by the National Natural Science Foundation of China (Grants 11602275, 11672308, 11672312, and 11532014.). The author thanks the people helping with this work and acknowledges the valuable suggestions from the peer reviewers.
- 2.Grinstead, J.H., Wilder, M.C., Olejniczak, J.O., et al.: Shock-heated air radiation measurements at lunar return conditions. In: Proceedings of 46th AIAA Aerospace Sciences Meeting and Exhibit, Nevada, January 7–10 (2008)Google Scholar
- 3.Sheikh, U.A., Morgan, R.G., McIntyre, T.J., et al.: Through surface and across surface vacuum ultraviolet spectral measurements in an expansion tube. In: Proceedings of 44th AIAA Thermophysic Conference, San Diego, June 24–27 (2013)Google Scholar
- 4.Sheikh, U.A., Morgan, R.G., Zander, F., et al.: Vacuum ultraviolet emission spectroscopy system for superorbital re-entries. In: Proceedings of 18th AIAA/3AF International Space Planes and Hypersonic Systems and Technologies Conference, Tours, September 24–28 (2012)Google Scholar
- 5.Potter, D.F., Gollan, R.J., Eichmann, T., et al.: Simulation of CO2–N2 expansion tunnel flows for the study of radiating shock layers. In: Proceedings of 46th AIAA Aerospace Sciences Meeting and Exhibit, Nevada, January 7–10 (2008)Google Scholar
- 7.Grinstead, J.H., Wilder, M.C., Reda, D.C., et al.: Advanced Spectroscopic and Thermal Imaging Instrumentation for Shock Tube and Ballistic Range Facilities. Technical Report (RTO, 2010)Google Scholar
- 8.Eichmann, T.N., Brandis, A., Potter, D., et al.: Radiating hypersonic flow studies using a super orbital expansion tube. In: Proceedings of 26th AIAA Aerodynamic Measurement Technology and Ground Testing Conference, Washington, June 23–36 (2008)Google Scholar
- 9.Whiting, E.E., Park, C., Liu, Y., et al.: NEQAIR96, Nonequilibrium and Equilibrium Radiative Transport and Spectra Program: User’s Manual (1996)Google Scholar
- 11.Johnston, C.O.: A comparison of EAST shock-tube radiation measurements with a new air radiation model. In: Proceedings of 46th AIAA Aerospace Sciences Meeting and Exhibit, Nevada, January 7–10 (2008)Google Scholar
- 13.Parker, R., Dufrene, A., MacLean, M., et al.: Emission measurements from high enthalpy flow on a cylinder in the LENS-XX hypervelocity expansion tunnel. In: Proceedings of 51st AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition, Texas, January 7–10 (2013)Google Scholar