Turbulent mixing in a confined rectangular wake
Turbulent mixing in a confined rectangular wake
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DOI：
10.1016/j.ces.2006.07.011
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发表时间：
2006-11
影响因子：
4.7
通讯作者：
Y. Liu;Hua Feng;M. Olsen;R. Fox;James C. Hill
中科院分区：
文献类型：
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作者：
Y. Liu;Hua Feng;M. Olsen;R. Fox;James C. Hill
用粒子图像测速仪(PIV)和平面激光诱导荧光(PLIF)技术研究了雷诺数为37,500，施密特数为1250的受限矩形尾迹内的液体湍流输运。分析了速度场和浓度场的平均速度、雷诺应力、湍动能、湍流耗散率、混合分数平均值、混合分数方差和一点组成概率密度函数等流动统计特性。计算流体动力学模型包括两层k-ε湍流模型、标量梯度扩散模型和标量耗散率模型。通过机械-标量时间尺度比考虑了低雷诺数对湍流输运的影响。实验结果与计算结果吻合较好。
Liquid-phase turbulent transport in a confined rectangular wake was investigated for a Reynolds number of 37,500 based on bulk velocity and the hydraulic diameter of the test section and a Schmidt number of 1250 using particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF). The velocity and concentration field data were analyzed for flow statistics such as the mean velocity, Reynolds stresses, turbulent kinetic energy, turbulent dissipation rate, mixture-fraction mean, mixture-fraction variance and one-point composition probability density functions (PDF). Computational fluid dynamics (CFD) models, including a two-layer k–ε turbulence model, a scalar gradient-diffusion model and a scalar dissipation rate model were validated against PIV and PLIF data collected at six downstream locations. Low-Reynolds-number effects on turbulent transport were taken into consideration through the mechanical-to-scalar time-scale ratio. The experimental and computational results were found to be in satisfactory agreement.