Development of Optical Gas Sensors for Tomographic Imaging in Combustion Processes

Laser-based absorption spectroscopy can be utilised in numerous industrial applications to measure species concentrations for process control, combustion diagnostics, environmental monitoring and emissions measurement, and can be applied in various forms (wavelength modulation spectroscopy - WMS, cavity ringdown spectroscopy - CRDS, photo-acoustic spectroscopy – PAS).

The Centre for Applied High Resolution Spectroscopy (CAHRS) within the Centre for Microsystems and Photonics at Strahclyde has over 20 years of experience implementing these techniques with a number of industrial and academic partners, including Rolls-Royce, Rolls-Royce Fuel Cells, Optosci Ltd, M Squared Lasers and the Universities of Manchester, Edinburgh and Southampton.

The CAHRS team have recently been awarded an EPSRC Platform Grant in collaboration with the University of Edinburgh and this studentship is funded by Strathclyde University to support the research in this Platform Grant. One of the main goals of this Platform Grant is to assess novel methods for tomographic image reconstruction by exploiting recent theoretical advances in WMS-based measurements. The aim of this studentship is to develop a WMS multi-species measurement and fitting approach to allow the simultaneous measurement of the concentration of a number of gases, as well as system temperature and pressure. This will be achieved with the continued support of Rolls-Royce through their interaction within the Platform Grant.

The student will begin by understanding the complexities of calibration free wavelength modulation techniques. They will then model theoretical absorption spectra to ascertain which spectral features of the target gases are suitable for measurement in a combustor. The chosen spectra will then be measured experimentally to ensure suitability, and to measure the temperature dependence of their broadening parameters. Field trials on combustors will then be carried out.