Towards Fast 2D Imaging of Gas Flows Using Focal Planar Arrays

Measurement of gas concentration and temperature distribution at high repetition rates in a plasma chemical reactor is important for the optimization of the reactor performance, for example, by placing more catalysts in the reaction zones. Tunable diode laser absorption spectroscopy combined with focal planar arrays is an effective method used for fast mapping of concentration and temperature in gaseous flows. A custom two dimensional (2D) high temperature gas flow cell has been constructed for the validation of the concept. An interband cascade laser and a focal planar array camera (Infratec ImageIR 5355) is employed for detection; 2D beam expanding optics to image the flow cell. The technique will be further developed for calibration and measurement of temperature and concentration, improvement of the speed etc., towards the realization of fast concentration and temperature measurements in a plasma reactor, targeting key plasma catalytic reactions such as methane valorization involving conversion of greenhouse gases such as methane to useful industrial precursors.