Experimental research of flow characteristics of coaxially atomized coal-water fuel

Abstract

Abstract Results of experimental studies of characteristics of coal-water fuel (CWF) stream in the process of its coaxial spraying in aerodynamic furnace simulator of a power boiler are presented in this paper. Mechanism of CWF atomization was researched at the following component ratios: 50% of coal and 50% of water. Coal fraction was 200 microns and less. Studies were conducted at pressures of 0.2 MPa (CWF) and 0.18 MPa (air). Visualization of CWF spray cone structure and assessment of the flow quality were made in the plane perpendicular to the axis of the cone on three segments. Geometrical parameters and velocities of CWF droplets in the process of spraying were established. Characteristic areas of CWF spray cone, which are formed in the process of atomization, were selected according to the obtained experimental results. Values of Weber number were calculated for corresponding velocities of CWF droplets. Characteristic stages of droplets breakup of the sprayed CWF were identified, and process conditions were formulated.