Semianalytical self-similar solution of bent-over jet in cross-flow
Semianalytical self-similar solution of bent-over jet in cross-flow
复制标题
DOI：
10.1061/(asce)0733-9399(1999)125:7(733
复制
发表时间：
1999-07
期刊：
影响因子：
--
通讯作者：
Joseph H. W. Lee;Lin Li;V. Cheung
中科院分区：
文献类型：
--
作者：
Joseph H. W. Lee;Lin Li;V. Cheung
通过对二维相似变换控制方程的数值求解，研究了横流中弯曲型动量射流横截面内的流场和标量场。半解析模型采用了湍流闭合的自由剪切层模型和横流方向上速度恒定的假设；整个解仅取决于衡量平流和扩散相对重要性的无量纲湍流混合参数λ。计算的流线和涡量场清楚地显示了所有λ的涡对流动。然而，标量分布的形状从圆形细胞生长到肾形的双峰结构。在λ=55的情况下，计算得到的射流轨迹、扩展和截面形状与实验符合得很好，尽管对稀释度的预测有些过高。结果表明，自由剪切层模型为e=0.0272Wml*，其中e、Wm和L*分别为涡动粘性、最大粘滞系数和最大粘滞系数。
The flow and scalar field in the cross section of a bent-over momentum jet in cross-flow has been investigated via a 2D numerical solution of the governing equations with similarity transformation. The semianalytical model employs a free shear layer model for turbulent closure and the assumption of a constant velocity in the direction of the cross-flow; the entire solution depends solely on a dimensionless turbulent mixing parameter λ that measures the relative importance of advection and diffusion. The computed streamlines and vorticity field clearly indicate a vortex-pair flow for all λ. The shape of the scalar distribution, however, grows from a circular cell to a kidney-shaped double peak structure. Using a value of λ = 55, the computed jet trajectory and spreading and the cross-sectional shape are in good agreement with the experiments, although the dilution is somewhat overpredicted. The results suggest a free shear layer model of e = 0.0272Wml*, where e, Wm, and l* are the eddy viscosity, maximum v...