Single- and dual-band collection toluene PLIF thermometry in supersonic flows
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Toluene PLIF has been applied to image temperature in supersonic flowfields containing shock waves. Single- and dual-camera imaging schemes with a single excitation wavelength (266 nm) are presented, and the dual-camera scheme is optimized for imaging temperature from 300 to 900 K. The single-camera technique is implemented to verify the diagnostic and image temperature in uniform pressure, uniformly seeded flowfields; calibration is done using the signal ratio measured across an oblique shock wave of known Mach number. The dual-camera technique utilizes the redshift of toluene fluorescence with increasing temperature for temperature imaging in non-uniform pressure and temperature flowfields. Both single- and dual-camera techniques are verified and demonstrated by imaging the flow behind normal shock waves and oblique shock waves, and the dual-camera technique is further extended to image temperature in the non-uniform pressure and temperature field behind a bow shock. Good agreement is observed between the measured and expected temperature distributions calculated from ideal shock relations or CFD solutions. The accuracy of each technique is also evaluated; for dual-camera thermometry, SNR in temperature ranging from 25 at 300 K to 15 at 900 K is observed in single-shot temperature images.
KeywordsMach Number Supersonic Flow Oblique Shock Incident Shock Wave Expansion Tube
This paper is based upon work supported by the Department of Energy under the Predictive Science Academic Alliance Program (PSAAP) at Stanford University, award number DE-FC52-08NA28614. This work is also supported by the Air Force Office of Scientific Research (AFOSR). The authors would also like to thank Jon Koch, Wieland Koban, and Christof Schulz for the toluene fluorescence spectra data they graciously provided. Additionally, Victor A. Miller is supported by the Claudia and William Coleman Foundation Stanford Graduate Fellowship.
- Cheung B (2011) Trace-based planar laser-induced fluorescence diagnostics: quantitative photophysics and time-resolved imaging. PhD thesis, Stanford UniversityGoogle Scholar
- Hanson RK (1986) Combustion diagnostics: planar flowfield imaging. In: 21st international symposium on combustion, the Combustions Institute, pp 1677–1691Google Scholar
- Heltsley WN, Snyder JA, Houle AJ, Davidson DF, Mungal MG, Hanson RK (2006) Design and characterization of the stanford 6 inch expansion tube. In: 42nd AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, Sacramento, California, AIAA, pp 2006–4443Google Scholar
- Koban W (2005) Photophysical characterization of toluene and 3-pentanone for quantitative imaging of fuel/air ratio and temperature in combustion systems. PhD thesis, University of HeidelbergGoogle Scholar
- Koch J (2005) Fuel tracer photophysics for quantitative planar laser-induced fluorescence. PhD thesis, Stanford UniversityGoogle Scholar
- Kohse-Höinghaus K, Jeffries JB (2002) Applied combustion diagnostics. Taylor & Francis, LondonGoogle Scholar
- Liepmann HW, Roshko A (1985) Elements of gasdynamics. Dover, New YorkGoogle Scholar
- McBride BJ, Zehe MJ, Gordon S (2002) NASA Glenn coefficients for calculating thermodynamic properties of individual species. Tech. Rep. TP-2002-211556, NASAGoogle Scholar
- Trimpi RL (1962) A preliminary theoretical study of the expansion tube, a new device for producing high-enthalpy short-duration hypersonic gas flows. Tech. rep., NASAGoogle Scholar
- Wolfrum J (1998) Lasers in combustion: from basic theory to practical devices. In: Proceeding of the Combustion Institute, vol 27Google Scholar