A second-order moment method of dense gas–solid flow for bubbling fluidization
A second-order moment method of dense gas–solid flow for bubbling fluidization
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DOI：
10.1016/j.ces.2009.08.005
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发表时间：
2009-12
影响因子：
4.7
通讯作者：
Sun Dan;Wang Shuyan;L. Huilin;Sheng Zhiheng;L. Xiang;W. Shuai;Zhao Yunhua;Wei Li-xin
中科院分区：
文献类型：
--
作者：
Sun Dan;Wang Shuyan;L. Huilin;Sheng Zhiheng;L. Xiang;W. Shuai;Zhao Yunhua;Wei Li-xin
本文提出了一个气固双流体模型，并采用二阶矩法封闭了流化方程组。根据颗粒流动力学理论，推导了颗粒相速度矩的输运方程。封闭方程的三阶矩的速度和流体颗粒的速度相关。前者是基于一个修改后的模型与增加的二进制碰撞概率的贡献，后者使用一个代数模型提出的Koch和Sangani [1999]。均质单分散气体流化床的颗粒压力和边缘稳定极限：动力学理论和数值模拟。Journal of Fluid Mechanics 400，229-263]. Strumendo和Canu [2002]提出的描述颗粒流的方程组的边界条件。非弹性球体稀颗粒流的矩量法。Physical Review E 66，041304/1-041304/20]中的方法进行了修改，考虑了壁和粒子之间碰撞引起的动量交换。采用气固双流体模型，结合颗粒的二阶矩模型，对鼓泡流化床内气体和颗粒的流动行为进行了模拟。预测了鼓泡流化床内颗粒的速度分布和动量分布。将预测结果与Muller等人[2008]测量的实验数据进行比较。颗粒温度：磁共振测量与离散元模型模拟的比较。Powder Technology 184，241-253]和Yuu等人[2000.小颗粒鼓泡流化床内空气和颗粒运动的数值模拟。粉末技术110，158-168]。在鼓泡流化床中。垂直方向的模拟二阶矩为1.1-2.5 [Muller，C.R.，荷兰，D. J.，Sedeman，A.J.，斯科特，SA，丹尼斯，J.S.，Gladden，L.F.，2008.颗粒温度：磁共振测量与离散元模型模拟的比较。粉末技术184，241-253]和1.1-4.0 [Yuu，S.，梅景，T.，Johno，Y.，2000.小颗粒鼓泡流化床内空气和颗粒运动的数值模拟。Powder Technology 110，158-168]，这是因为气泡流化床中颗粒的速度波动较高。Gidaspow等人[2004]使用的每单位体积密度的气泡状雷诺法向应力。流体动力学流态化使用动力学理论：一个新兴的范例2002年面粉丹尼尔讲座。粉末技术148，123-141。从模拟的流体动力学速度计算。预测结果与Muller等人[2008]测量的实验二阶矩一致。颗粒温度：磁共振测量与离散元模型模拟的比较。Powder Technology 184，241-253]和Yuu等人[2000.小颗粒鼓泡流化床内空气和颗粒运动的数值模拟。粉末技术110，158-168]。
A gas–solid two-fluid model with the second-order moment method is presented to close the set of equations applied to fluidization. With the kinetic theory of granular flow, transport equations for the velocity moments are derived for the particle phase. Closure equations for the third-order moments of velocity and for the fluid–particle velocity correlation are presented. The former is based on a modified model with the contribution of the increase of the binary collision probability, and the latter uses an algebraic model proposed by Koch and Sangani [1999. Particle pressure and marginal stability limits for a homogeneous monodisperse gas-fluidized bed: kinetic theory and numerical simulations. Journal of Fluid Mechanics 400, 229–263]. Boundary conditions for the set of equations describing flow of particles proposed by Strumendo and Canu [2002. Method of moments for the dilute granular flow of inelastic spheres. Physical Review E 66, 041304/1–041304/20] are modified with the consideration of the momentum exchange by collisions between the wall and particles. Flow behavior of gas and particles is performed by means of gas–solid two-fluid model with the second-order moment model of particles in the bubbling fluidized bed. The distributions of velocity and moments of particles are predicted in the bubbling fluidized bed. Predictions are compared with experimental data measured by Muller et al. [2008. Granular temperature: comparison of magnetic resonance measurements with discrete element model simulations. Powder Technology 184, 241–253] and Yuu et al. [2000. Numerical simulation of air and particle motions in bubbling fluidized bed of small particles. Powder Technology 110, 158–168]. in the bubbling fluidized beds. The simulated second-order moment in the vertical direction is 1.1–2.5 [Muller, C.R., Holland, D.J., Sedeman, A.J., Scott, S.A., Dennis, J.S., Gladden, L.F., 2008. Granular temperature: comparison of magnetic resonance measurements with discrete element model simulations. Powder Technology 184, 241–253] and 1.1–4.0 [Yuu, S., Umekage, T., Johno, Y., 2000. Numerical simulation of air and particle motions in bubbling fluidized bed of small particles. Powder Technology 110, 158–168] times larger than that in the lateral direction because of higher velocity fluctuations for particles in the bubble fluidized bed. The bubblelike Reynolds normal stresses per unit bulk density used by Gidaspow et al. [2004. Hydrodynamics of fluidization using kinetic theory: an emerging paradigm 2002 Flour–Daniel lecture. Powder Technology 148, 123–141.] are computed from the simulated hydrodynamic velocities. The predictions are in agreement with experimental second-order moments measured by Muller et al. [2008. Granular temperature: comparison of magnetic resonance measurements with discrete element model simulations. Powder Technology 184, 241–253] and fluctuating velocity of particles measured by Yuu et al. [2000. Numerical simulation of air and particle motions in bubbling fluidized bed of small particles. Powder Technology 110, 158–168].