Date of Award
Master of Science
Trevor M. Moeller
Christopher S. Combs, Feng-Yuan Zhang
Database parameters for line spectra are collected from many studies and require independent verification for use in the design and measurements of laser absorption spectroscopy systems. While many lower temperature lines are well characterized, the higher temperature and pressure lines found in studies of combustion products rely on theoretical scaling. High-temperature calibration devices are therefore desired to allow experimental validation of parameters under test conditions. For this research, the design of a high-temperature, three-zone gas cell is proposed as a replacement for the current absorption cell system at The University of Tennessee Space Institute (UTSI). This new design, a prototype of which has been built and tested at The Technical University of Denmark, allows for measurements of test gas samples at uniform temperatures of at least 1300K. A computational fluid dynamics (CFD) model is shown for the current UTSI gas cell that has <6% difference with measured flange temperatures and <7% dierence from axial gas temperature measurements. This CFD model is then used to predict material and centerline gas temperatures expected at the limit of the proposed design. The model results show that the proposed cell design has a high temperature uniformity in the test section and flange temperatures well below the temperature limits of the desired O-ring materials and indicate that water-cooling will be unnecessary.
Johnson, Travis Lee, "Analysis of a High-Temperature Spectroscopic Gas Cell Design. " Master's Thesis, University of Tennessee, 2018.