Study On Dust Diffusion Characteristics And Control Strategy Under The Condition Of Impact Flow

In response to "13th five-year plan" to promote green transformation of traditional manufacturing industries, and encourage enterprises to technology and equipment renovation of the green concept, China's foundry industry workshop of dust pollution has become necessary research.Firstly, in this paper, It analyzes dust diffusion phenomenon and its influencing factors through the modeling workshop field observations.Then, it uses computational fluid dynamics(CFD) software to build two-dimensional and three-dimensional unloading sand model,in order to investigate the changes of mass flow rate, initial falling velocity, drop height and orifice diameter which influence on fine dust movement. It shows that the inhalable particles is influenced by a drag force from dropping particle of multiple diameters used in the practical project, so that the fine particles are dominated by downward movement and dust diffusion. However the single size of group particles present a gradual rise and outward expansion of the "plume" phenomenon. Both have a large difference. Dust movement will be impeded in practical engineering, such as irregular flow which makes the diffusion regularity different, It also explores the multi-size particles movement under the transverse airflow interference. The results show that different airflow patterns enable multi-size particles to appear stratification phenomenon, and inhalable particles spread to the outermost layer which are most influenced by airflow, which provides the dust control system the theoretical data to deal with moving dust source pollution problems. Moreover,as for inhalable particles control, this paper presents three control airflow,simulates and contrasts their controlling effect. Considering the exhaust system of airflow control, equipment installation and effectiveness and other factors, it's better to use downdraft airflow to control dust. Lastly, it simulates the pollution sources height, exhaust port size, and pollution source dissemination speed these three factors on the impact of dust suction air capture efficiency.