Utilizing Near-IR Tunable Laser Absorption Spectroscopy to Study Detonation and Combustion Systems
Abstract
A Hencken burner, RDE, and a detonation tube were studied using a TDM-TDLAS system to measure water absorption features over two spectral regions (7,435 to 7,442 cm-1 and 7,465 to 7,471 cm-1) near 1.3 micrometers. These absorption features were t with simulated spectra using data from the HITEMP database to obtain temperatures and water concentrations for the three systems. Velocity was calculated for the RDE system using the Doppler shift of the spectral lines. To perform the calculations necessary to obtain these results (temperature, concentration, and velocity) a GUI was developed with supporting code. A Hencken burner ame was studied at three di erent heights above the burner surface, for two di erent fuels; ethylene (C2H4) and methane (CH4), both at various equivalence ratios. The C2H4 Hencken burner temperatures matched fairly well with the adiabatic temperatures once edge e ects were taken into account, however, the CH4 ame did not match as well. The exhaust of the RDE was studied at various equivalence ratios using a hydrogen-air mixture (H2-air). The exhaust temperatures were found to linearly increase with equivalence ratio, from 1,300 K ( 1) to 1,500 K (1.4) and uctuated with a standard deviation of approximately 50 K. The exhaust velocities of the RDE were found to be independent of equivalence ratio with an average value of 360 m/s and a standard deviation of 50 m/s. A detonation tube was studied at various equivalence ratios and initial pressures, also using an H2- air mixture. Preliminary results are presented for the detonation tube, however, further work in that area is required.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 27, 2014
- Accession Number
- ADA600718
Entities
People
- Christopher J. Mcgahan
Organizations
- Air Force Institute of Technology