Sensitivity analysis of main control factors for efficiency of submerged jet crushing coal containing gas

Abstract

In order to study the influencing factors of crushing efficiency of coal containing gas under submerged jet, the influence of different water jet impact conditions on coal crushing efficiency was studied, and the fluid solid coupling model of water jet crushing coal containing gas was established. Taking coal crushing depth and coal crushing volume as indexes, the effects of jet angle, jet velocity, nozzle diameter and initial target distance on coal crushing efficiency were investigated. The results show that: under the condition of submerged jet, bullet shaped crushing pit is formed in the initial stage of jet coal breaking process. With the process of coal breaking, the diameter of crushing pit increases and the depth extends downward; under the condition of submerged jet, the depth and volume of coal breaking are positively correlated with the change of jet velocity and nozzle diameter, and negatively correlated with the change of initial target distance, the depth of broken coal pit reaches the maximum value when the jet is perpendicular to the coal, and the broken coal volume increases first, then decreases and then rises with the increase of jet angle, reaching the maximum value at 90°; based on the orthogonal experiment, the primary and secondary order of theinfluence of different jet parameters on the coal breaking efficiency of submerged jet is as follows: jet inclination angle, jet velocity, nozzle diameter and initial target distance.

Keywords

• submerged jet
• numerical simulation
• breaking coal efficiency
• main controlling factors
• orthogonal experiment
• sensitivity analysis
• coal containing gas