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埋管由于具有改善流场特性,强化颗粒混合和传热.被广泛用于流态化设备中,本文基于LES-DEM耦合方法,对含有单根埋管的三维鼓泡床进行传热和磨损特性的研究.其中气相在大涡模拟框架下对控制方程过滤后进行求解,固相在颗粒尺度采用离散单元方法进行跟踪.在表观气速为1.6 m/s下,对固相和气相瞬时特性进行分析.研究了埋管传热及磨损分布规律,发现埋管的存在显著地改变了流场和固相的流动行为.埋管瞬时传热系数与壁面附近颗粒浓度及速度有较强的关联特性,颗粒浓度小、速度大的区域.局部传热系数较大.同时.埋管局部磨损特性受流场和固相特性影响,在埋管底部和上部磨损较大,水平方向磨损较少.
Buried pipes are widely used in fluidized equipment due to their improved flow field characteristics and enhanced particle mixing and heat transfer. In this paper, a three-dimensional bubbling bed containing a single buried pipe is subjected to heat transfer and wear based on the LES-DEM coupling method In the gas phase, the governing equations are filtered after filtering in the framework of large eddy simulation, and the solid phase is tracked by the discrete element method at the particle size.When the apparent gas velocity is 1.6 m / s, The heat transfer and wear distribution of the buried pipe were studied.The results show that the existence of the buried pipe significantly changes the flow behavior of the flow field and the solid phase.The transient heat transfer coefficient of the pipe is strongly related to the particle concentration and velocity near the wall Correlation characteristics, small particle concentration and high velocity, large local heat transfer coefficient, while the local wear characteristics of the buried pipe are affected by the flow field and the solid phase characteristics, with larger wear on the bottom and upper part of the buried pipe and less wear in the horizontal direction .