Propane-air mixture combustion assisted by MW discharge in a speedy airflow

In this paper, results are presented from an experimental investigation of propane-air combustion in a stationary microwave (MW) discharge at different conditions. In these experiments, a deeply undercritical discharge is initiated in the base of an electromagnetic vibrator, which is immersed in cold supersonic airflow. Two schemes for mixing propane with air are considered. In the first scheme, a propane-air mixture is delivered through the vibrator and is ignited at the outlet from the vibrator. In the second scheme, propane delivered through the vibrator mixes with air captured by an inlet hole in the vibrator nose prior to being also ignited by the MW discharge at the base of the vibrator. Propane combustion with efficiency of approximately 60% was demonstrated at a mixture velocity up to 200 m/s in the combustion region. The heat release reaches approximately 1 kW at a propane mass flow rate of 2 (.) 10(-2) g/s and discharge power of approximately 200 W.