Stanford Advisors


All Publications


  • Four-dimensional laser absorption cinematography of species and temperature dynamics at 2 kHz in reacting flows OPTICS LETTERS Wei, C., Spearrin, R. 2024; 49 (1): 141-144

    Abstract

    A four-dimensional (4D) mid-infrared laser absorption imaging technique has been developed and demonstrated for quantitative, time-resolved, volumetric measurements of temperature and species concentration in dynamic combustion flows. This technique employs a dual high-speed infrared camera setup to capture turnable radiation from a quantum cascade laser near 4.85 µm to resolve rovibrational absorption transitions of carbon monoxide at two orthogonal projection angles. The laser is modulated with a customized waveform to adaptively resolve two target transitions with an increased density of data samples in proximity to the transition peaks, therefore ensuring accurate and quantitative spectral interpretation while minimizing the required frame rate. A 3D masked Tikhonov regularized inversion was performed to reconstruct spectrally resolved absorbance at every grid point of each frame, which enables subsequent interpretation of local gas properties in time. These methods are applied to achieve quantitative 4D cinematography of temperature and carbon monoxide in a propagating C2H4/O2 flame with a spatial pixel resolution of ∼70 µm and a temporal resolution of 2 kHz.

    View details for DOI 10.1364/OL.512240

    View details for Web of Science ID 001171249600007

    View details for PubMedID 38134172

  • Fiber-coupled optical probe for laser absorption diagnostics in shock tube experiments with high concentrations of non-monatomic species PROCEEDINGS OF THE COMBUSTION INSTITUTE Wei, C., Knubben, J. C., Strand, C. L., Hanson, R. K. 2024; 40 (1-4)
  • Transient analysis of solar pyrolysis and hydrogen yield via interband cascade laser absorption spectroscopy of methane, acetylene, ethylene, and ethane APPLICATIONS IN ENERGY AND COMBUSTION SCIENCE Jeevaretanam, B., Abuseada, M., Wei, C., Minesi, N. Q., Fisher, T. S., Spearrin, R. 2023; 16
  • Concentrated solar-thermal methane pyrolysis in a porous substrate: Yield analysis via infrared laser absorption PROCEEDINGS OF THE COMBUSTION INSTITUTE Wei, C., Abuseada, M., Jeevaretanam, B., Fisher, T. S., Spearrin, M. 2023; 39 (4): 5581-5589
  • Quantitative volumetric laser absorption imaging of methane and temperature in flames utilizing line-mixing effects PROCEEDINGS OF THE COMBUSTION INSTITUTE Wei, C., Schwarm, K. K., Pineda, D. I., Spearrin, R. 2023; 39 (1): 1229-1237
  • Turbulence-induced bias in time-averaged laser absorption tomography of correlated concentration and temperature fields with a first-order correction COMBUSTION AND FLAME Wei, C., Perakis, N., Pineda, D., Egolfopoulos, F. N., Ihme, M., Spearrin, R. 2022; 242
  • Carbon oxidation in turbulent premixed jet flames: A comparative experimental and numerical study of ethylene, n-heptane, and toluene COMBUSTION AND FLAME Pineda, D., Paxton, L., Perakis, N., Wei, C., Luna, S., Kahouli, H., Ihme, M., Egolfopoulos, F. N., Spearrin, R. 2020; 221: 371–83