High-Resolution Tunable Diode Laser Spectroscopy of Methane

摘要

The feasibility of using tunable diode laser spectroscopy for measurement of methane concentration in turbine engine exhausts was investigated. An experimental program was accomplished in which the foreign gas broadening parameters of the methane R(O)A line of the v3 fundamental band were measured for nitrogen and carbon dioxide broadening. The temperature range was extended from the room temperature data available in the literature to 1000K, typical of turbine engine exhausts. The range of concentrations and path lengths over which the technique is feasible was established. A literature survey on typical turbine engine emissions was conducted from which it was determined that the technique may be applicable at augmented power settings, but methane concentrations are too small for idle and intermediate power settings.