Central recirculation zone induced by the DBD plasma actuation

Abstract

Central recirculation zone (CRZ) is commonly formed in the near field of the injector exit by the vane swirler and used to stabilize the flame. In our experiment, a CRZ induced by the DBD plasma actuation was observed in the low swirl burner configuration for the first time, which clearly demonstrated that the mechanism of the combustion control by the plasma swirler is mainly through the aerodynamic effect. Three dielectric barrier discharge (DBD) actuators are placed in a circular array around the axis to generate ionic wind in the circumferential direction of the injector. Characteristics of the flow field have been measured using Laser Doppler Anemometry. It is found that a central recirculation zone with the shape of an ellipsoid is formed in the non-reacting flow field with the plasma actuation. The position of the upstream stagnation point was determined by the strength of the actuation. Although the CRZ disappears in the reacting flow field as the result of combustion heat release, the influence of the discharge on the flame lift-off height is noticeable. The results demonstrate that swirl enhancement by the plasma swirler is feasible, flexible and effective as a non-intrusive measure for flow control.

Studies on Mg–Ba mixed oxide catalysts for continuous glycerol transesterification to glycerol carbonate

“…Among the other reported alternate pathways, transesterification of GLY with dimethyl carbonate (DMC) is a promising and facile method. [7][8][9] More interestingly, the generated by-product methanol can be easily separated from the reaction mixture and could be used for the synthesis of DMC from CO 2 ; thereby no waste will be generated by this process and the entire cycle is sustainable. [10][11][12][13][14][15] Several homogeneous base catalysts such as NaOH, K 2 CO 3 and NaOMe were explored for the transesterification of glycerol with DMC.…”