Development of Optical Gas Sensors for Tomographic Imaging in Combustion Processes

基于激光的吸收光谱可以在许多工业应用中用于测量过程控制、燃烧诊断、环境监测和排放测量的物质浓度，并且可以以各种形式应用（波长调制光谱- WMS、腔衰荡光谱- CRDS、光声光谱- PAS）。应用高分辨率光谱学中心（CAHRS），在微系统和光子学中心在曼彻斯特部门有超过20年的经验，实施这些技术与一些工业和学术合作伙伴，包括劳斯莱斯，LG燃料电池，Optosci有限公司，M平方激光，曼彻斯特大学，爱丁堡和南安普顿。该项目的主要目标之一是通过利用基于WMS的测量的最新理论进展来评估用于断层图像重建的新方法，所述基于WMS的测量承诺不仅对气体的物种浓度进行成像，本研究的目的是开发一种高帧率的WMS方法，用于水蒸气浓度和系统温度测量。学生将开始理解的复杂性校准自由波长调制技术。然后，他们将对理论吸收光谱进行建模，以确定目标气体的哪些光谱特征适合在燃烧室中进行测量。然后将通过实验测量所选光谱以确保适用性，并测量其加宽参数的温度依赖性。然后，他们将开发实时算法和传感器系统，以允许现场燃烧器测量水蒸气和燃烧器温度。

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 in the EEE department has over 20 years of experience implementing these techniques with a number of industrial and academic partners, including Rolls-Royce, LG Fuel Cells, Optosci Ltd, M Squared Lasers, Universities of Manchester, Edinburgh and Southampton.One of the main goals of this project is to assess novel methods for tomographic image reconstruction by exploiting recent theoretical advances in WMS-based measurements that promise to image not only the species concentration of a gas, but also its temperature and pressure profiles .The aim of this studentship is to develop a high frame rate WMS approach for water vapour concentration and system temperature measurements. 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 gas 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. They will then develop real-time algorithms and sensor systems to allow in-situ combustor measurements of water vapour and combustor temperature.