Education
- Ph.D., Auburn University, 2018
- MS, Auburn University, 2017
- BAE, Auburn University, 2011
Work Experience
- National Institute of Aerospace, Research Engineer, 2017-present
- NIFT Intern, NASA Langley, summer 2015
Research Areas/Expertise
- Light Field Imaging
- Particle Image Velocimetry
- 3D Particle Reconstruction
- Doppler global velocimetry
Current Research
A plenoptic multi-color imaging pyrometer
Typical instruments used to in spectroscopy have high spectral resolution (>100 wavelengths) and low spatial resolution (point or line) or high spatial resolution (2D image) and low spectral resolution (2-3 wavelengths). This project focuses on a middle ground with a lower resolution image but with 7-19 wavelengths, based on the plenoptic camera. This approach should allow more accurate temperature measurements, when compared to 2/3 color pyrometers, while also adding spatial resolution. Current work is focusing on applying this technology to test samples in the Hyperspectral Materials Environmental Test System (HYMETS).
High-speed Doppler global velocimetry using a pulse-burst laser
Doppler global velocimetry (DGV) is a measurement technique which measures the velocity of tracer particles immersed in the working fluid, by measuring the Doppler shift of reflected laser light. The Doppler shift is directly proportional to the velocity of the particle, which is assumed to be an accurate measurement of the working fluid. The benefit of this technique is that it scales to large facilities since it does not need to spatially resolve individual particles, which of particular interest in the large facilities located at NASA LaRC. By using a pulse-burst laser, which is capable of repetition rates of 10 kHz to 10 MHz, this technique can be extended to high-speeds to measure transient events in super/hypersonic facilities. In addition, by scanning the laser frequency during a burst the dynamic range (range of velocities that can be measured) of the technique can be extended using cross-correlation DGV. Current work is focused on exploring the use of these techniques in the unitary plan wind tunnel and creating compact camera instrumentation.
Publications
Journal Articles
Fahringer, T., Thurow, B., “Plenoptic particle image velocimetry with multiple plenoptic cameras” Measurement Science & Technology, Vol 29, 075202, 2018
Elise Munz Hall, Timothy W. Fahringer, Daniel R. Guildenbecher, and Brian S. Thurow, “Volumetric calibration of a plenoptic camera,”} Applied Optics57, 914-923
Klemkowsky, J., Fahringer, T., Clifford, C., Bathel, B., Thurow, B., “Plenoptic Background Oriented Schlieren Imaging”Measurement Science & Technology, Vol 28, 095404, 2017
Fahringer, T., Thurow, B “Filtered refocusing: a volumetric reconstruction algorithm for plenoptic-PIV” Measurement Science & Technology, Vol 27, 094005, 2016
Deem, E., Zhang, Y., Cattafesta, L., Fahringer, T., Thurow, B., “On the resolution of plenoptic PIV” Measurement Science & Technology, Vol 27, 084003, 2016
Fahringer, T., Lynch, K., Thurow, B., “Volumetric particle image velocimetry with a single plenoptic camera” Measurement Science & Technology, Vol 26, 115201, 2015
Conference Papers/Presentations
Fahringer, T., Thurow, B., “The effect of microlens size on the performance of single-camera plenoptic PIV,” 19th Int. Symp. on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal, July 16-19, 2018.
Fahringer, T., Danehy, P., Hutchins, W. “Design of a Multi-Color Plenoptic Camera for Snapshot Hyperspectral Imaging,” AIAA Paper 2018-3627, 34th AIAA Aerodynamic Measurement Technology and Ground Testing Conference, Atlanta, Georgia, June 17-21, 2018.
Fahringer, T., Thurow, B. “Progress toward two-camera plenoptic-PIV,” AIAA Paper 2017-4069, 33rd AIAA Aerodynamic Measurement Technology and Ground Testing Conference, Denver, Colorado, June 5-9, 2017.
Klemkowsky, J., Fahringer, T., Thurow, B., Bathel, B., “Preliminary Comparison Between Conventional and Plenoptic Background Oriented Schlieren Imaging,” AIAA Paper 2017-4067, 33rd AIAA Aerodynamic Measurement Technology and Ground Testing Conference, Denver, Colorado, June 5-9, 2017.
Fahringer, T., Thurow, B., Humphreys, W., Bartram, S., “Comparison of stereo-PIV and plenoptic-PIV measurements on the wake of a cylinder in NASA ground test facilities,” AIAA Paper 2017-0023, 55th AIAA Aerospace Sciences Meeting, Grapevine, Texas, January 9-13, 2017.
Hall, E., Fahringer, T., Thurow, B., Guildenbecher, G., “Volumetric calibration of a plenoptic camera,” AIAA Paper 2017-1642, 55th AIAA Aerospace Sciences Meeting, Grapevine, Texas, January 9-13, 2017.
Danehy, P., Hutchins, W., Fahringer, T., Thurow, B., “A Plenoptic Multi-Color Imaging Pyrometer,” AIAA Paper 2017-1645, 55th AIAA Aerospace Sciences Meeting, Grapevine, Texas, January 9-13, 2017.
Klemkowsky, J., Fahringer, T., Clifford, C., Thurow, B., “3D Imaging of Density Gradients Using Plenoptic BOS” 69th Annual Meeting of the APS Division of Fluid Dynamics, November 20-22, 2016, Portland, Oregon
Fahringer, T., Thurow, B. “On the development of filtered refocusing: A volumetric reconstruction algorithm for plenoptic-PIV,” 11th International Symposium on Particle Image Velocimetry, Santa Barbara, CA USA, September 2015
Fahringer, T., Thurow, B. “Comparing volumetric reconstruction algorithms for plenoptic PIV,” AIAA Paper 2015-1221, 53rd AIAA Aerospace Sciences Meeting, Kissimmee, Florida, January 4-8, 2015.
Thomason, C., Fahringer, T., Thurow, B “Calibration of a Microlens Array for a Plenoptic Camera,” AIAA Paper 2014-0396, 52nd AIAA Aerospace Sciences Meeting, National Harbor, Maryland, January, 2014.
Fahringer, T., Thurow, B. “3D Particle Position Reconstruction Accuracy in Plenoptic PIV,” AIAA Paper 2014-0398, 52nd AIAA Aerospace Sciences Meeting, National Harbor, Maryland, January, 2014.
Thurow, B., Fahringer, T., Johnson, K., and Hellman, S., “Comparison of plenoptic PIV and stereo PIV measurements in a wing tip vortex,” 17th Int. Symp. on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal, July 7-10, 2014.
Thomason, C., Fahringer, T., Johnson, K., Thurow, B. “Modeling the effect of refraction at a flat interface on plenoptic particle reconstruction,” AIAA Paper 2014-2662, 30th AIAA Aerodynamic Measurement Technology and Ground Testing Conference, Atlanta, Georgia, June 16-20, 2014.
Thurow, B., Fahringer, T., “Recent development of volumetric PIV with plenoptic camera,” Proceedings of the 10th International Symposium on Particle Image Velocimetry, Delft, The Netherlands, July 1-3, 2013
Fahringer, T., Thurow, B., “The Effect of Grid Resolution on the Accuracy of Tomographic Reconstruction Using a Plenoptic Camera,” AIAA Paper 2013-003951st AIAA Aerospace Sciences Meeting, Dallas, Texas, January, 2013.
Thurow, B., Fahringer, T., “Volumetric PIV with a plenoptic camera,” 56th Annual APS-DFD Meeting, San Diego, CA, November 18-20, 2012.
Fahringer, T., Thurow, B., “Tomographic reconstruction of a 3D flow field using a plenoptic camera,” AIAA Paper 2012-2826 42nd AIAA Fluid Dynamics Conference, New Orleans, Louisiana, June 2012.
Lynch, K., Fahringer, T., Thurow, B., “Three-Dimensional Particle Image Velocimetry Using a Plenoptic Camera,” AIAA Paper 2012-1056 50th AIAA Aerospace Sciences Meeting, Nashville, Tennessee, January 2012.