Session

session5

Location

Space Dynamics Laboratory, Auditorium Rm B

Start Date

5-9-2022 10:50 AM

End Date

5-9-2022 11:00 AM

Description

Results from proof-of-concept tests using fiber-optic cables inserted into the combustion port of a lab-scale hybrid rocket system are reported. The fiber optic cables transmit optical signals to miniature spectrometers and allow in-situ optical characterization of the combustion plume properties including flame temperature and combustion plume species. Multiple firings with burn durations varying from 5 to 25 seconds were performed. The fiber optic sensors survived all tests and resulting rocket performance data were correlated with in-situ optical spectra data. When the optical measurements were adjusted to account for the spectrometer transfer function and the resulting spectra were curve-fit to Planck's radiation law, the sensed ensemble mean flame temperature agrees to within 20 °C with the analytically predicted flame temperature. Additionally, local maxima in the optical spectra correspond to species known to exist in the hybrid combustion plume. Based on these preliminary test results, this simple in-situ measurement system shows considerable promise.

Available for download on Tuesday, May 09, 2023

Share

COinS
 
May 9th, 10:50 AM May 9th, 11:00 AM

Development of Optical Systems for In-Situ Measurements of High-Temperature Combustion Plumes

Space Dynamics Laboratory, Auditorium Rm B

Results from proof-of-concept tests using fiber-optic cables inserted into the combustion port of a lab-scale hybrid rocket system are reported. The fiber optic cables transmit optical signals to miniature spectrometers and allow in-situ optical characterization of the combustion plume properties including flame temperature and combustion plume species. Multiple firings with burn durations varying from 5 to 25 seconds were performed. The fiber optic sensors survived all tests and resulting rocket performance data were correlated with in-situ optical spectra data. When the optical measurements were adjusted to account for the spectrometer transfer function and the resulting spectra were curve-fit to Planck's radiation law, the sensed ensemble mean flame temperature agrees to within 20 °C with the analytically predicted flame temperature. Additionally, local maxima in the optical spectra correspond to species known to exist in the hybrid combustion plume. Based on these preliminary test results, this simple in-situ measurement system shows considerable promise.