摘要
基于标准k-ε湍流模型并辅以多重参考系法,利用FLUENT软件对立式三轴搅拌釜内单相和固液两相混合过程分别进行三维数值模拟。结果表明:相对于单相体系,固体粒子的加入抑制了槽内轴向循环流的高度,降低了槽内液相总体速度;槽底固相沉积面积随转速增大而减小。利用浓度判据,得到完全离底悬浮临界转速Njs为635r/min。由单位体积功率随转速增大而增大和槽底平均固相浓度随转速增大而减小的规律分析得出,既能达到完全离底悬浮,又能使搅拌功耗最小的最佳转速为640r/min。
Based on standard k-ε turbulence model and multiple refer- ence frame （MRF） method, the 3D numerical simulation for the mixing process of the single-phase and solid-liquid two-phase in stirred tank with triaxial agitator was made using FLUENT soft- ware. The results indicate that compared with the single-phase sys- tem, the adding of solid particles can suppress the axial height of the circulation flow and reduce the overall speed of liquid phase in the tank. The solid deposition area at bottom tank decreases with the in- creasing of rotor speed. Meanwhile, the solids just suspended impel ler speed Nis was 635 r/min which obtained by the Concentration Cri- terion. From the variation trend of the specific volume power increas- ing and mean solid concentration at bottom tank decreasing with the increase of the speed , it could be derived that the optimum speed which makes the solids just-suspended and the minimum consumed power is 640 r/min.
出处
《食品与机械》
CSCD
北大核心
2013年第3期169-172,186,共5页
Food and Machinery
关键词
立式三轴搅拌釜
固液两相
最佳转速
搅拌功率
计算流体力学(CFD)
vertical three-impeller stirred tank
two-phase of solid-liq-uid
optimum speed
stirring power
computational fluid dynamics（CFD）
