深井换热设备中悬浮颗粒物沉积规律的数值模拟研究

Numerical Simulation Study on the Deposition Patterns of Suspended Particles in Deep Borehole Heat Exchanger Equipment

摘要: 随着矿井开采深度的不断加深，浅部通风降温方式难以满足深部通风需求，因此需开展人工制冷降温技术来改善井下空气环境。然而，在制冷系统实际运行过程中，受复杂热湿环境和多组分工质条件影响，其主要换热设备的换热效果和使用寿命均受到显著制约。文章针对涌水和空气悬浮颗粒物的沉积问题进行数值模拟研究，分析颗粒在水和空气流体中的受力情况，模拟不同密度颗粒在改变两相流速度和粒径变化条件下的最基本沉积，揭示颗粒在换热面上的沉积规律，从而为换热设备的性能选取和优化提供指导。结果表明，当流体流速达到2.5 m/s以后，颗粒沉积量变化趋势减缓，因此选择合理的流速可以解决管内沉积问题；此外，随空气流速的增加，沉积率呈现“升高–降低–升高”的变化特征，且颗粒沉积率在一定流速时随粒径的增大而升高。

Abstract: As mining depth increases, conventional shallow ventilation cooling methods struggle to meet the demands of deep mining operations, making artificial refrigeration technology necessary to improve the underground air environment. However, during the actual operation of refrigeration systems, the complex thermal and humid conditions, along with the influence of multi-component working fluids, significantly affect both the heat transfer efficiency and service life of the main heat exchange equipment. This study conducts numerical simulations on the deposition of suspended particles from water inrush and air, analyzing the forces acting on particles in water and air flows. By simulating the fundamental deposition behavior of particles with different densities under varying two-phase flow velocities and particle sizes, the deposition patterns of particles on heat exchange surfaces are determined. The findings provide guidance for the selection and optimization of heat exchanger performance. The results indicate that when the fluid flow velocity reaches 2.5 m/s, the increase in particle deposition rate slows down, suggesting that selecting an appropriate flow velocity can mitigate in-tube deposition issues. Additionally, with increasing air flow velocity, the deposition rate exhibits a “rise-fall-rise” trend. Under certain flow velocities, the particle deposition rate increases with larger particle sizes.