Optical in Situ Versus Probe Measurements of Nitric Oxide Concentration as a Function of Axial Position in a Combustor Exhaust.

摘要

Nitric oxide (N0) concentration was measured at three axial stations (6.5, 12, and 25 nozzle diameters downstream of a combustor nozzle exit) in a jet engine combustor exhaust by a gas-sampling probe in conjunction with conventional gas analyzers and an optical resonance absorption technique. The gas analyzer system permitted measurements of NO, NO sub x, CO, CO sub 2, and C sub x, H sub y (total hydrocarbons) whereas the optical absorption technique permitted measurement of NO only. The combustor was exhausted into a test cell of slightly less than atmospheric pressure and was operated at an inlet air temperature of 589 K, a total pressure of 344.3 kPa, and a fuel-to-air ratio (f/a) of 0.02. A multiprobe rake was used to acquire emissions, total pressure and temperature, and static pressure data at the measurement stations. The measurements of total pressure, total temperature, and measured static pressure were used to determine static temperature and pressure profiles at each measurement station, which are required for determining NO concentration by the optical absorption technique.