Increasing the rate of capture of pollutants by local suction due to the use of an external swirling jet. Part 2. Results of numerical and experimental studies

Abstract

To capture pollutants in many buildings and structures, it is necessary to use local suction systems. It is proposed to increase one of the criteria for the effectiveness of local suction — the rate of capture of pollutants — due to the impact of a swirling annular jet and the occurrence of a reverse air flow. To do this, the circular suction was placed coaxially in an external cylindrical casing, in which the air flow was twisted due to the tangential supply of two supply jets into the casing, resulting in a vortex dome, which contributes to increasing the efficiency of such a vortex suction. Experimentally and numerically, the change in the axial velocity of air at a distance from the vortex suction was investigated for 11 structures, in each of which 4 different ratios of intake and supply air flow rates were set. In the studied applications of the proposed suction systems, the speed increases significantly at a certain range of distance from them. A combination of design-mode parameters that contribute to the highest rate of capture by vortex suction is determined. The results obtained can be used to design effective suction systems for capturing pollutants. Ill. 6. Ref. 10.