油砂干馏系统的DEM-CFD耦合模拟

DEM-CFD COUPLED SIMULATION OF OIL SANDS RETORTING IN A ROTARY KILN

数值模拟相对于实验研究具有速度快,成本低,操作性强等较大优势,在各行各业都有广泛应用。当前的油砂干馏过程数值模拟主要基于计算流体力学方法而且仍处于较初级阶段,距离实际应用尚有巨大距离。根据油砂物料的离散特点,引入离散元数值模拟方法,对油砂颗粒在干馏炉内的运动、铺展、前进过程进行还原,同时与计算流体力学方法进行耦合,引入油砂与炉壁以及油砂之间的热传递过程。初步研究表明离散元数值模拟计算较好地展示了颗粒在炉内运动铺展的过程,以及通道内颗粒受气流携带的过程。

Numerical simulation is increasingly applied in various fields as a cost-effective and time-saving alternative approach when compared with the experimental method. The present numerical simulation for oil sands retorting in a rotary kiln is mainly based on computational fluid dynamics (CFD) method and has not been applied to practical production. In view of the discrete characteristics of oil sands,a discrete element method (DEM) is employed to simulate the collision,spreading,transporting,and mixing of oil sands in a kiln. DEM is further coupled with CFD to calculate the particle-fluid two phases flow in a pipe. The results reveal that this DEM-CFD coupling method is able to get dynamic details of oil sands particles in a rotary kiln very well.