ABSTRACT

To address the coal gangue fracture heat transfer problem, the law of heat transfers and temperature distribution in the coal gangue fracture is studied. The temperature distribution in a coal gangue fracture under 12 conditions (with or without the obstacle, and various heat flows) is simulated via Fluent numerical simulation. The results show that the heat flow velocity, temperature and obstacle are important factors in inhibiting heat transfer oxidation spontaneous combustion in the coal gangue fracture. When the heat flow temperature is constant, the low-velocity heat flow causes a large temperature drops in the coal gangue fracture; when the heat flow velocity is constant, the high-temperature heat flow also produces a large temperature drops effect; when the obstacle is present and the heat flow produces vortex pass through the obstacle, increasing the energy loss in the coal gangue fracture, causing the temperature in the coal gangue fracture to drop rapidly, and reach the lowest in the position of the obstacle. Obstacles can effectively inhibit the heat transfer characteristics in the coal gangue fracture and reduce the risks of oxidation spontaneous combustion of gangue after grouting.

摘要

针对煤矸石裂隙传热问题，研究了煤矸石裂隙传热及温度分布规律。通过Fluent数值模拟，模拟了12种工况（有无障碍物、各种热流）下煤矸石裂缝中的温度分布。结果表明，热流速度、温度和障碍物是抑制煤矸石裂缝传热氧化自燃的重要因素。当热流温度一定时，低速热流使煤矸石裂缝温度下降较大；当热流速度一定时，高温热流也产生较大的温降效应；当障碍物存在且热流产生涡流穿过障碍物时，增加煤矸石裂隙中的能量损失，使煤矸石裂隙内温度迅速下降，在障碍物位置达到最低。障碍物可以有效抑制煤矸石裂缝中的传热特性，降低注浆后矸石氧化自燃的风险。