Study on morphology features of hydraulic flushing hole based on ore drawing theory

in order to study the morphology features of the hydraulic fushing hole in softcoal with the references of Bergmark-Roos equation in the ore drawing theory.a tracing equation of the coal and rock migration was established in the coal discharging process with the hydrauic fushing related to the bulk coal and rock gravity in the hydraulic flushing hole,coal and rock friction force,wate ation of the hydraulic flushing hole features was derived.With the help of MATLAB,an analag ellipsoid of the hydraulic fushing hole morphologywas drawn and the mathematical integration was applied to derive a formula to calculate the coal volume and the hydraulic fushing hole diamerer.The fiting proven was conducted with the coal discharging data ofthe hydraulic fushing hole collected from Xintian Mine.The corelation coeffcient was 0.931 4,the square sum of the error was 0.28,during the seam opening process in Zhongmacun Mine,the backills found in the holes were analogy ellipsoids mostly. Therefore,Bergmark-Roos equation applied to determine the hydraulic fushing hole morphology.hole diameter and other parameters was feasible and reliable ,and could effectively guide the related numerical simulation and site appication of the hydraulic fushing hole.