【目的】模拟预测三七种子颗粒群的悬浮速度,为气固两相流的模拟仿真提供参考依据。【方法】利用PS-20物料漂浮速度试验台测量悬浮速度;采用离散元和计算流体力学相耦合的方法模拟台架试验,并模拟颗粒体积分数对流场影响;借助普拉诺夫斯基修正式验证各体积分数下颗粒群悬浮速度模拟值。【结果】体积分数对流场影响显著。体积分数接近0时,台架试验颗粒群悬浮速度范围为7.14~9.32 m·s-1、平均值为8.23 m·s-1,模拟结果为7.08~9.30 m·s-1、平均值为8.19 m·s-1;当体积分数在2.58%、3.87%、5.16%、7.74%时,模拟试验的悬浮速度分别为8.52、8.72、8.96、9.46 m·s-1,悬浮速度的理论计算值分别为8.53、8.79、9.06、9.71 m·s-1,最大误差为2.6%。【结论】采用模拟技术可建立体积分数低于9.03%时的悬浮速度预测模型;在未出现较大涡流的情况下,可利用离散元和计算流体力学相耦合的方法模拟预测不同体积分数下颗粒群的悬浮速度。
【Objective】To stimulate and predict suspension speed of notoginseng seed particle swarm,and to provide a reference for simulating gas-solid two-phase flow. 【Method】The suspension speeds of seed particles swarm were surveyed by the PS-20 material floating speed test bed. Bench test were stimulated by coupling discrete element method with computation fluid mechanics,and the influences of seed particle swarm volume fraction on the flow field were stimulated. The suspension speed analog values under different volume fractions were validated using the pulanuofusiji modified formula. 【Result】Volume fractions of seed particle swarm had significant effects on flow field. When the particle volume fraction was zero,the seed particle swarm suspension speeds ranged from 7. 14 to 9. 32 m·s- 1and the mean value was 8. 23 m·s- 1,while simulation speeds ranged from 7. 08 to 9. 30 m·s- 1and average of 8. 19m·s- 1. When particles volume fractions were 2. 58%,3. 87%,5. 16% and 7. 74%,the simulation results were 8. 52,8. 72,8. 96 and 9. 46 m·s- 1respectively,while the theoretical calculated values were8. 53,8. 79,9. 06 and 9. 71 m·s- 1respectively with the maximum error of 2. 6%. 【Conclusion】The particle swarm suspension speed predicted model can be built using stimulated technology when particles volume fraction is below 9. 03%. The particle swarm suspension speeds under different volume fractionscan be predicted by coupling discrete element method with computation fluid mechanics.