Numerical study of aspiration efficiency of local exhaust devices under action of cross draughts of dust-laden airflow

• Main Authors: Averkova, O. A., Goltsov, A. B., Logachev, K. I., Uvarov, V. A.
• Format: Conference Proceeding
• Language: English
• Subjects: Acceleration; Air flow; Dust; Efficiency; Exhaust hoods; Flow velocity; Fluid flow; Orifices; Terminal velocity
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0130640

This paper is a study of aspiration efficiency of local exhaust devices approached by an incident flow of dust-laden air. Known past studies dedicated to determining the aspiration efficiency of a circular pipe facing a flow of dust-air mixture include. In contrast, our study is concerned with a more general problem: given a stream of dustladen air approaching a local exhaust device in the form of a circular exhaust hood, we determine aspiration efficiency as a function of exhaust hood length and tilt angle, incident airflow velocity, and terminal velocity of dust particles. Using the method of discrete vortices, a mathematical model of the motion of dust particles in the flow in front of a circular exhaust hood with an axis of symmetry perpendicular to the acceleration vector of gravity is developed, taking into account the formation of two vortex zones at the entrance to the hood, the initial velocity and direction of emission of dust particles. The dependences of the capture range of dust particles formed at different heights above the impenetrable plane on the following parameters are determined: air flow velocity at the exhaust orifice; initial velocities o dust particles and it's terminal velocity; exhaust hood flange lengths.