摘要
采用RNGk-ε模型,并分别结合标准壁面函数法和两层模型的壁面函数法对横向紊动射流流场结构进行了数值模拟。得到了射流与主气流速度比R等于2和4时对称面内速度的沿程分布,以及对称面内的速度场和压力场。结果表明:射流出口背风侧流动出现了分离,存在尾迹区,R值增加,尾迹区范围也相应增加;标准壁面函数法无法模拟出分离区内较大的压力梯度变化,所计算的流场分离区较大;两种壁面函数法预测的沿程速度分布和实验的数据大体一致,但是在最大速度点的下方,两层模型的壁面函数法与实验结果接近,从而说明两层模型的壁面函数法更适于求解横向紊动射流问题。
The RNGk-ε turbulence model with two near-wall treatment, respectively the standard wall function method and the two-layer wall function method,was adopted to simulate the characteristics of the turbulent jet in crossflow. The velocity and pressure fields were got under the condition of R , jet-crossflow velocity ratios, being2 and 4. The results show that the separation events in the lee of the jet orifice are found,and the area of wakes increases under the condition of R equaling to 4. The greater variety of the pressure gradient in the wake area cannot be computed exactly by using the standard wall function method, which results in a larger separation area in the velocity fields. The results based on the two-layer wall function method are good agreement with the experimental measurements, and it can be concluded that this method is suitable for simulating the jet-to-crossflow.
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
2006年第1期20-25,共6页
Chinese Journal of Hydrodynamics
关键词
横流
紊动射流
湍流模型
壁面函数法
crossflow
turbulent jet
turbulence model
wall function method
