Abstract
In this study both qualitative and quantitative flow visualization techniques are used to examine the complex flow field developed during the interaction of a plane shock wave with a compound profile. Shearing interferometry and direction-indicating colour schlieren are implemented in conjunction with high-speed time-resolved imaging. Comparisons between the results provided by the two flow visualization systems are made at incident shock strengths of Mach 1.28 and Mach 1.35. The results from both systems indicate the complex nature of the transient compression and expansion systems developed during the interaction behind the various shock fronts. The direction-indicating results prove valuable in eliminating the ambiguity with respect to the sign of the high-order fringes found in the shearing interferometry results.
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References
Cords PH (1968) A high resolution, high sensitivity color schlieren method. SPIE J 6:85–88
Etoh TG, Poggemann D, Ruckelshausen A, Theuwissen A, Kreider G, Folkerts H-O, Mutoh H, Kondo Y, Maruno H, Takubo K, Soya H, Takehara K, Okinaka T, Takano Y, Reisinger T, Lohmann C (2002) A CCD image sensor of 1 Mframes/s for continuous imaging capturing of 103 frames. In: Technical digest of international solid state circuit conference. IEEE 0-7803-7335-9/02, pp 45–48
Kleine H (2001) Measurement techniques and diagnostics: flow visualization. In: Ben-Dor G, Igra O, Elperin T (eds) Handbook of shock waves. Academic Press, San Diego, pp 685–738
Kleine H, Grönig H (1991) Color schlieren methods in shock wave research. Shock Waves 1:51–63
Merzkirch W (1987) Flow visualization, 2nd edn. Florida Academic Press, Orlando
Oertel H Sr., Oertel H Jr. (1989) Optische strömungsmeßtechnik. Karlsruhe, G. Braun
Ohtake H, Hayashida T, Kitamura K, Arai T, Yonai J, Tanioka K, Maruyama H, Etoh TG (2006) 300,000-pixel ultrahigh-speed high-sensitivity CCD and single-chip color camera mounting this CCD. NHK Broadcast Technol 28:2–9
Prescott R, Gayhart EL (1951) A method of correction of astigmatism in schlieren systems. J Aeronaut Sci 18:69
Settles GS (1970) A direction-indicating color schlieren system. AIAA J 8:2282–2284
Settles GS (1985) Colour-coding schlieren techniques for the optical study of heat and fluid flow. Int J Heat Fluid Flow 6:3–15
Sturtevant B, Kulkarny VA (1976) The focusing of weak shock waves. J Fluid Mech 73(4):651–671
Acknowledgments
The authors wish to extend a special thanks to Prof. T. G. Etoh and Prof. K. Takehara of Kinki University, Osaka, Japan, for the use of their exceptional high-speed camera which made this work possible. The authors also wish to thank both the South African National Research Foundation for the KIC travel grant along with project Fluxion for their financial support during the first author’s post-graduate studies. The first author is also in deep gratitude to the CSIR for providing the time necessary to complete this work.
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MacLucas, D.A., Skews, B.W. & Kleine, H. High-speed imaging of shock wave focusing in concave profiles using shearing interferometry and direction-indicating colour schlieren. J Vis 18, 521–529 (2015). https://doi.org/10.1007/s12650-014-0261-y
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DOI: https://doi.org/10.1007/s12650-014-0261-y