Analysis of influencing factors on dust separation efficiency of new virtual impact separator based on CFD technology

Respirable dust in coal mines endangers the health of workers. To detect its concentration accurately and separate it effectively from the total dust volume is the first priority. In this study, to enhance the inadequate separation efficiency of respirable dust in coal mines and achieve continuous separation, a virtual 3D dust separation model was developed based on the virtual impact theory. The internal flow field, pressure field, and particle field distribution of the impact separator were simulated and analyzed. A model sample was fabricated using 3D printing technology, and the aerosol particle separation efficiency of the sample was experimentally evaluated with an optical particle size spectrometer and an experimental dust test platform. The results demonstrate that the separation efficiency of the virtual impact separator is better for 1 and 7 mu m particles (95.52% and 2.33%, respectively) and worse for 3, 4.33, and 5 mu m particles (78.91%, 59.37%, and 52.68%, respectively). The deviation between the experimental and simulation results ranges from 0.22% to 5.20%. When the inlet air velocity is 2.5 m/s, the separation efficiency of the virtual impact separator is generally better. Moreover, its trend aligns well with the BMRC curve; the deviation ranges from 0.65% to 4.40%. Consequently, this separator proves to be a viable instrument for efficient respirable dust separation during coal mining.