Optimization of dust removal hose layout positions for cutting different excavation face areas by a roadheader

In order to improve the dust removal efficiency of the long-pressure and short-pumping local ventilation excavation face, the distribution characteristics of the wind flow field of the excavation face and the dust control effect of the whole process of cutting and tunneling of the comprehensive excavator was quantitatively analyzed, and the optimal deployment position of the dust removal duct in the excavation roadway section was optimized.Firstly, according to the force analysis of dust particles under the action of wind flow, the dust particle movement model in the roadway wind flow considering the dust flow characteristics such as the roadway wind flow state and particle size was constructed. The section of the excavation face was divided into nine dust-producing areas to truly restores the dust-generating process in the cutting process of the excavation face. Tthe N-S model and model of the wind flow field of the fully mechanized excavation face combined, the numerical model of wind flow and dust migration of the fully integrated excavation face under the whole process of cutting and tunneling of the comprehensive excavator was established by taking the Baode coal mine 81205 Glue Transportation Slot comprehensive excavation face as the research object. On this basis, the dust removal ducts were simulated and analyzed under the conditions of different dust source areas, which were located in the “upper position of the roadway”, “the upper position of the roadway side gang” and the “middle position of the roadway side gang” under the conditions of different dust source areas.The results showed that the dust migration and diffusion in the roadway under the conditions of dust generation sources in different cutting areas showed obvious differences, and the change trend of dust migration and diffusion under the simulated conditions was basically the same, indicating that the subdivision of dust sources in the head-on section of the excavation face by the palace grid cutting method was more sand experimental uitable for the actual cutting and dust production process of the excavation face. Under the simulation and test conditions, the dust removal duct was located in the upper part of the roadway side, the driver's position (10 m away from the excavation face) was in the vortex negative pressure area, and the wind speed and flow field in the personnel operation area (28 m away from the excavation face) was stable, which was the most conducive to dust control, and the dust removal duct was located in the upper part of the roadway. The dust removal duct was located in the upper part of the roadway side and the breathing height position (1.5m height from the roadway floor), the dust concentration value was the lowest, the dust diffusion area and the total dust diffusion area were the smallest, and it was more obvious when the comprehensive excavator cuted the upper and middle areas of the head-on section of the excavation face.