用改进的RNGk-ε 模型模拟旋风分离器内的强旋流动

 在RNG k-ε湍流模型的基础上，对模型常数和近壁面处理方法加以改进，并将其应用于旋风分离器内强旋流动的数值模拟。将计算结果与RNG k-ε模型、Reynolds应力输运模型(RSM)的计算结果及实验数据进行比较。随后采用欧拉-拉格朗日模型（湍流模型为RSM）和欧拉-欧拉模型（湍流模型为改进的RNG k-ε模型）分别对旋风分离器内的气、固两相流动进行计算，考察了旋风分离器内的颗粒浓度分布特点。结果表明，改进的RNG k-ε模型和RSM对旋风分离器内流场分布的预测结果与实验结果比较吻合, 并且前者所需计算时间却大大缩短，更适合工业应用。使用改进的RNG k-ε湍流模型的欧拉-欧拉多相流模型可以重现旋风分离器内的气、固两相流动特点，并应用于旋风分离器的优化设计。

NUMERICAL SIMULATION OF STRONGLY SWIRLING FLOW IN CYCLONE SEPARATOR USING AN ADVANCED RNG k-εMODEL

Based on the renormalization group (RNG) κ-εturbulence model, the model coefficient and near-wall treatment were modified. The modified RNG κ-ε turbulence model was applied to the numerical simulation of single-phase strongly rotational flow in a cyclone separator. And the simulation results of RNG κ-ε model, the advanced RNG κ-ε model and Reynolds stress model (RSM) were compared with the experimental data. Then, numerical simulation of the gas and solid phase flows in cyclone separator was carried out by applying Eulerian-Lagrangian model (Turbulence flow model of RSM) and Eulerian-Eulerian model (Turbulence flow model of the advanced RNG κ-ε model) respectively. The effects of the different two-phase models on the flow behavior and solid distribution in cyclone separator were studied. It was shown that the agreement between the results of the advanced RNG κ-ε model and RSM and those of experiments were obtained. The advanced RNG κ-ε model can be more useful in practical engineering calculation due to its time consuming dramatically decreased. The Eulerian-Eulerian model (Turbulence flow model of the advanced RNG κ-ε model) also can preferably reappear the flow characteristics in cyclone separator, which can be useful for design optimization of cyclone separators