Academic Appointments


  • Sr Research Engineer, Mechanical Engineering

All Publications


  • Laser Absorption Sensor Targeting Potassium for Hypersonic Velocity, Temperature, and Enthalpy Measurements AIAA JOURNAL Schwartz, T., Finch, P. M., Strand, C. L., Hanson, R. K., Luo, Y., Yu, W. M., Austin, J. M., Hornung, H. G. 2023

    View details for DOI 10.2514/1.J062620

    View details for Web of Science ID 001003665400001

  • Shock-Tube Measurements of Atomic Nitrogen Collisional Excitation in 8000-12000 K Partially Ionized Nitrogen-Argon Mixtures. The journal of physical chemistry. A Finch, P. M., Granowitz, Z. N., Streicher, J. W., Krish, A., Strand, C. L., Hanson, R. K. 2023

    Abstract

    We report on shock-tube experiments measuring the collisional excitation of atomic nitrogen using tunable diode laser absorption spectroscopy (TDLAS). Conditions behind the reflected shocks ranged from 8000 to 12000 K and 0.1 to 1.1 atm in mixtures of 1 or 2% molecular nitrogen (N2) in argon (Ar). Absorption from the transition between atomic nitrogen quantum states 4P to 4D at 868 nm was used to monitor the formation of electronically excited nitrogen. Population measurements of the 4P state were made at a rate of 50 kHz. In connection with these measurements, a multitemperature kinetic mechanism is proposed for nitrogen excitation. Measurements suggest a multistage process. In early test times, a period of induction due to N2 dissociation is followed by a rise via heavy particle excitation. The dominant channel causing this excitation is believed to be N + N N(4P) + N with a measured forward rate constant of 3.65 * 10-18 exp(-119892/T) [m3/s]. As test time evolves, the excitation of 4P, referred to as N*, is subsequently interrupted and then resumes, as the kinetic environment becomes increasingly electron-dominated. The most impactful reactions of the mechanism are optimized to reduce the residual between simulations and the measurements. The measured N* populations indicate strong, though indirect, sensitivity to adjacent processes, including the excitation of metastable nitrogen, and ionization channels.

    View details for DOI 10.1021/acs.jpca.2c07839

    View details for PubMedID 36745871

  • Measurements of T5 Shock Tunnel Freestream Temperature, Velocity, and Composition AIAA JOURNAL Finch, P. M., Girard, J. J., Schwartz, T., Strand, C. L., Hanson, R. K., Yu, W. M., Austin, J. M., Hornung, H. G. 2023

    View details for DOI 10.2514/1.J062383

    View details for Web of Science ID 000924854700001

  • A laser-absorption sensor for in situ detection of biofuel blend vapor in engine intakes PROCEEDINGS OF THE COMBUSTION INSTITUTE Clees, S., Cha, D. H., Biswas, P., Boddapati, V., Cassady, S. J., Strand, C. L., Hanson, R. K., French, B., Gilmour, A., Hawk, K. C., Stitt, J. M., Ferlet, X. 2023; 39 (1): 1307-1316
  • Line mixing study of carbon monoxide near 4.7 mu m broadened by nitrogen, helium, and hydrogen JOURNAL OF MOLECULAR SPECTROSCOPY Su, W., Ding, Y., Strand, C. L., Hanson, R. K. 2022; 390
  • Collisional broadening and pressure shift of the potassium resonance doublets by nitrogen, helium, and hydrogen at high temperatures JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Ding, Y., Vandervort, J. A., Freedman, R. S., Strand, C. L., Marley, M. S., Hanson, R. K. 2022; 283
  • Investigating Arcjet Mixing and Enthalpy Loss Using Atomic Oxygen Laser Absorption Spectroscopy AIAA JOURNAL Salazar, D., Strand, C. L., Hanson, R. K., MacDonald, M. E. 2022; 60 (2): 976-984

    View details for DOI 10.2514/1.J060274

    View details for Web of Science ID 000802220400034

  • Line mixing study on the fundamental rovibrational band of nitric oxide near 5.3 mu m JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Su, W., Boulet, C., Almodovar, C. A., Ding, Y., Strand, C. L., Hanson, R. K. 2022; 278
  • Measurements of Reflected Shock Tunnel Freestream Nitric Oxide Temperatures and Partial Pressure AIAA JOURNAL Girard, J. J., Finch, P. M., Strand, C. L., Hanson, R. K., Yu, W. M., Austin, J. M., Hornung, H. G. 2021; 59 (12): 5266-5275

    View details for DOI 10.2514/1.J060596

    View details for Web of Science ID 000800025200032

  • Thermometry and speciation for high-temperature and -pressure methane pyrolysis using shock tubes and dual-comb spectroscopy MEASUREMENT SCIENCE AND TECHNOLOGY Pinkowski, N. H., Biswas, P., Shao, J., Strand, C. L., Hanson, R. K. 2021; 32 (12)
  • Line mixing in the nitric oxide R-branch near 5.2 mu m at high pressures and temperatures: Measurements and empirical modeling using energy gap fitting JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Almodovar, C. A., Su, W., Choudhary, R., Shao, J., Strand, C. L., Hanson, R. K. 2021; 276
  • Shock tube measurements of high-temperature argon broadening and shift parameters for the potassium D1 and D2 resonance transitions JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Ding, Y., Vandervort, J. A., Strand, C. L., Hanson, R. K. 2021; 275
  • Quantum-cascade-laser-based dual-comb thermometry and speciation at high temperatures MEASUREMENT SCIENCE AND TECHNOLOGY Pinkowski, N. H., Cassady, S. J., Strand, C. L., Hanson, R. K. 2021; 32 (3)
  • Scientific accomplishments and research avenues of Professor Ronald Hanson COMBUSTION AND FLAME Davidson, D. F., Jeffries, J. B., Oehlschlaeger, M. A., Strand, C. L. 2021; 224: 2–5
  • Development of a Stark shift measurement technique using excited-state oxygen atoms to determine electron number density in shock heated O-2/Ar above 10 000 K PLASMA SOURCES SCIENCE & TECHNOLOGY Li, Y., Wang, S., Strand, C. L., Hanson, R. K. 2021; 30 (2)
  • Time-resolved, single-ended laser absorption thermometry and H2O, CO2, and CO speciation in a H-2/C2H4-fueled rotating detonation engine PROCEEDINGS OF THE COMBUSTION INSTITUTE Cassady, S. J., Peng, W., Strand, C. L., Dausen, D. F., Codoni, J. R., Brophy, C. M., Hanson, R. K. 2021; 38 (1): 1719-1727
  • An In Situ Laser-Absorption Sensor for Crank Angle-Resolved Temperature, Pressure, and Humidity in Intake-Runner Flows SAE INTERNATIONAL JOURNAL OF ENGINES Cassady, S. J., Cha, D. H., Pinkowski, N. H., Strand, C. L., Hanson, R. K., Ferlet, X., French, B., Mernone, B. J., Gilmour, A., Stitt, J. M. 2021; 14 (4): 551-568
  • Temperature-dependent absorption cross section measurements for propene, 1-butene, cis-/trans-2-butene, isobutene and 1,3-butadiene in the spectral region 8.4-11.7 mu m JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Ding, Y., Su, W., Johnson, S. E., Strand, C. L., Hanson, R. K. 2020; 255
  • Two-color frequency-multiplexed IMS technique for gas thermometry at elevated pressures APPLIED PHYSICS B-LASERS AND OPTICS Wei, W., Peng, W., Wang, Y., Shao, J., Strand, C. L., Hanson, R. K. 2020; 126 (3)
  • Analysis of laser absorption gas sensors employing scanned-wavelength modulation spectroscopy with 1f-phase detection APPLIED PHYSICS B-LASERS AND OPTICS Peng, W., Strand, C. L., Hanson, R. K. 2020; 126 (1)
  • Dual-comb Spectroscopy for High-temperature Reaction Kinetics Measurement Science and Technology Pinkowski, N. H., Ding, Y., Strand, C. L., Horvath, R., Geiser, M. 2020

    View details for DOI 10.1088/1361-6501/ab6ecc

  • Two-temperature Collisional-radiative Modeling of Partially Ionized O2-Ar Mixtures over 8000-10,000 K Behind Reflected Shock Waves. The journal of physical chemistry. A Li, Y. n., Wang, S. n., Strand, C. L., Hanson, R. K. 2020

    Abstract

    The collisional excitation kinetics of atomic oxygen was studied behind reflected shock waves using tunable diode laser absorption spectroscopy. A test gas mixture of 1% O2/Ar was shock-heated to temperatures between 8000 and 10,000 K and pressures between 0.15 and 1 atm. The time evolution of the atomic oxygen population in the 3 s 5S0 state was monitored by laser absorption at 777.2 nm. The measured O(3 s 5S0) population revealed multistage behavior that was not observed in previous measurements over a temperature range of 5300-7200 K. To interpret the multistage behavior, a three-level collisional-radiative model for atomic oxygen excitation kinetics was developed. The model utilized two independent temperatures, that is, heavy particle translational temperature Ttr and electron translational temperature Te, to describe the fundamental rate constants of atomic oxygen excitation because of collisions with heavy particles and electrons, respectively. The heavy particle excitation rate was inferred from the early stage of the measurement to be k(3P →5S0) = 3.4 × 10-27 (T/K)0.5(1.061 × 105 + 2 (T/K)) exp(-1.061 × 105 K/T) ± 50% m3 s-1. The electron impact excitation rate constant of oxygen, electron impact, and heavy particle impact ionization rate constants of Argon were modified in the model to match the experimental population time histories. The modified rate parameters are also reported for the temperature range explored in the current study.

    View details for DOI 10.1021/acs.jpca.0c00466

    View details for PubMedID 32306734

  • Calibration-free breath acetone sensor with interference correction based on wavelength modulation spectroscopy near 8.2 mu m APPLIED PHYSICS B-LASERS AND OPTICS Schwarm, K. K., Strand, C. L., Miller, V. A., Spearrin, R. 2020; 126 (1)
  • R-branch line intensities and temperature-dependent line broadening and shift coefficients of the nitric oxide fundamental rovibrational band JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Almodovar, C. A., Su, W., Strand, C. L., Hanson, R. K. 2019; 239
  • High-pressure, high-temperature optical cell for mid-infrared spectroscopy JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Almodovar, C. A., Su, W., Strand, C. L., Sur, R., Hanson, R. K. 2019; 231: 69–78
  • A two-wavelength ethylene-absorption temperature diagnostic MEASUREMENT SCIENCE AND TECHNOLOGY Cassady, S. J., Susa, A. J., Ferris, A. M., Strand, C. L., Hanson, R. K. 2019; 30 (3)
  • Single-Ended Sensor for Thermometry and Speciation in Shock Tubes Using Native Surfaces IEEE Sensors Journal Peng, W. Y., Wang, Y., Cassady, S. J., Strand, C. L., Hanson, R. K. 2019
  • Single-ended mid-infrared laser-absorption sensor for time-resolved measurements of water concentration and temperature within the annulus of a rotating detonation engine PROCEEDINGS OF THE COMBUSTION INSTITUTE Peng, W., Cassady, S. J., Strand, C. L., Goldenstein, C. S., Spearrin, R., Brophy, C. M., Jeffries, J. B., Hanson, R. K. 2019; 37 (2): 1435–43
  • Mid-infrared laser absorption spectroscopy of NO2 at elevated temperatures JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Sur, R., Peng, W. Y., Strand, C., Spearrin, R. M., Jeffries, J. B., Hanson, R. K., Bekal, A., Haider, P., Poonacha, S. P., Vartak, S., Sridharan, A. K. 2017; 187: 364-374
  • Line intensities and temperature-dependent line broadening coefficients of Q-branch transitions in the v(2) band of ammonia near 10.4 mu m JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Sur, R., Spearrin, R. M., Peng, W. Y., Strand, C. L., Jeffries, J. B., Enns, G. M., Hanson, R. K. 2016; 175: 90-99
  • Line intensities and temperature-dependent line broadening coefficients of Q-branch transitions in the v2 band of ammonia near 10.4 μm. Journal of quantitative spectroscopy & radiative transfer Sur, R., Spearrin, R. M., Peng, W. Y., Strand, C. L., Jeffries, J. B., Enns, G. M., Hanson, R. K. 2016; 175: 90-99

    Abstract

    We report measured line intensities and temperature-dependent broadening coefficients of NH3 with Ar, N2, O2, CO2, H2O, and NH3 for nine sQ(J,K) transitions in the ν2 fundamental band in the frequency range 961.5-967.5 cm-1. This spectral region was chosen due to the strong NH3 absorption strength and lack of spectral interference from H2O and CO2 for laser-based sensing applications. Spectroscopic parameters were determined by multi-line fitting using Voigt lineshapes of absorption spectra measured with two quantum cascade lasers in thermodynamically-controlled optical cells. The temperature dependence of broadening was measured over a range of temperatures between 300 and 600 K. These measurements aid the development of mid-infrared NH3 sensors for a broad range of gas mixtures and at elevated temperatures.

    View details for DOI 10.1016/j.jqsrt.2016.02.002

    View details for PubMedID 29225373

    View details for PubMedCentralID PMC5722251

  • Quantification of Supersonic Impulse Flow Conditions via High-Bandwidth Wavelength Modulation Absorption Spectroscopy AIAA JOURNAL Strand, C. L., Hanson, R. K. 2015; 53 (10): 2978-2987

    View details for DOI 10.2514/1.J053842

    View details for Web of Science ID 000361468800014

  • Hypersonic Scramjet Testing via Diode Laser Absorption in a Reflected Shock Tunnel JOURNAL OF PROPULSION AND POWER Schultz, I. A., Goldenstein, C. S., Strand, C. L., Jeffries, J. B., Hanson, R. K., Goyne, C. P. 2014; 30 (6): 1586-1594

    View details for DOI 10.2514/1.B35220

    View details for Web of Science ID 000344145000018

  • Fitting of calibration-free scanned-wavelength-modulation spectroscopy spectra for determination of gas properties and absorption lineshapes APPLIED OPTICS Goldenstein, C. S., Strand, C. L., Schultz, I. A., Sun, K., Jeffries, J. B., Hanson, R. K. 2014; 53 (3): 356-367

    Abstract

    The development and initial demonstration of a scanned-wavelength, first-harmonic-normalized, wavelength-modulation spectroscopy with nf detection (scanned-WMS-nf/1f) strategy for calibration-free measurements of gas conditions are presented. In this technique, the nominal wavelength of a modulated tunable diode laser (TDL) is scanned over an absorption transition to measure the corresponding scanned-WMS-nf/1f spectrum. Gas conditions are then inferred from least-squares fitting the simulated scanned-WMS-nf/1f spectrum to the measured scanned-WMS-nf/1f spectrum, in a manner that is analogous to widely used scanned-wavelength direct-absorption techniques. This scanned-WMS-nf/1f technique does not require prior knowledge of the transition linewidth for determination of gas properties. Furthermore, this technique can be used with any higher harmonic (i.e., n>1), modulation depth, and optical depth. Selection of the laser modulation index to maximize both signal strength and sensitivity to spectroscopic parameters (i.e., gas conditions), while mitigating distortion, is described. Last, this technique is demonstrated with two-color measurements in a well-characterized supersonic flow within the Stanford Expansion Tube. In this demonstration, two frequency-multiplexed telecommunication-grade TDLs near 1.4 μm were scanned at 12.5 kHz (i.e., measurement repetition rate of 25 kHz) and modulated at 637.5 and 825 kHz to determine the gas temperature, pressure, H2O mole fraction, velocity, and absorption transition lineshape. Measurements are shown to agree within uncertainty (1%-5%) of expected values.

    View details for DOI 10.1364/AO.53.000356

    View details for Web of Science ID 000330172300007

    View details for PubMedID 24514120

  • Supersonic Mass-Flux Measurements via Tunable Diode Laser Absorption and Nonuniform Flow Modeling 49th AIAA Aerospace Sciences Meeting / New Horizons Forum and Aerospace Exposition Chang, L. S., Strand, C. L., Jeffries, J. B., Hanson, R. K., Diskin, G. S., Gaffney, R. L., Capriotti, D. P. AMER INST AERONAUT ASTRONAUT. 2011: 2783–91

    View details for DOI 10.2514/1.J051118

    View details for Web of Science ID 000297968200017