INHOMOGENEOUS TWO-STREAM TURBULENT MIXING USING THE TURBULENT KINETIC ENERGY EQUATION
INHOMOGENEOUS TWO-STREAM TURBULENT MIXING USING THE TURBULENT KINETIC ENERGY EQUATION
复制标题
使用湍流动能方程的非均匀两流湍流混合
DOI：
10.21236/ad0705578
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发表时间：
1970
期刊：
影响因子：
--
通讯作者：
Harry L. Maynard
中科院分区：
文献类型：
--
作者：
M. Laster;Harry L. Maynard
文摘：研究了湍流动能方法在非均匀两流湍流混合计算和二维对称尾迹计算中的应用。对氢气-空气和空气-空气的同轴混合流动进行了混合计算，并与实验数据进行了比较。通过假定湍流剪应力与湍动能成正比，将湍流动能方程转化为湍流剪应力的输运方程。湍流动能的侧向扩散采用通量模型。能量耗散被模拟为类似于各向同性湍流的形式。通过假设普朗特数和刘易斯数是统一的，质量和能量传输被结合到分析中。所得到的偏微分方程组是双曲型的，并选择特征线法进行求解。理论方法在计算中固有地结合了湍流结构的历史，这在物理上比基于局部流动特性的湍流结构模型更可接受。结果表明，湍流动能方法对两流混合问题具有较好的适用性，但还需进一步发展，才能用于常规工程计算。对平板后的尾迹进行了计算，计算结果与实验数据吻合较好。湍流动能扩散通量模型和能量耗散模型的计算结果与实验结果吻合较好。
Abstract : A study was made on applying the turbulent kinetic energy approach to inhomogeneous two-stream turbulent mixing calculations and to calculations of a two-dimensional symmetric wake. Mixing calculations are made and compared with experimental data for coaxial hydrogen-air and air-air mixing flows. The turbulent kinetic energy equation is transformed into a transport equation for the turbulent shear stress by assuming that the turbulent shear stress is directly proportional to the turbulent kinetic energy. A flux model is assumed for the lateral diffusion of turbulent kinetic energy. The energy dissipation is modeled to a form similar to that derived for isotropic turbulence. Mass and energy transport are incorporated to the analysis by assuming the Prandtl and Lewis numbers to be unity. The resulting set of partial differential equations is hyperbolic and the method of characteristics are chosen for their solution. The theoretical method inherently incorporates history of the turbulent structure in the calculations which is physically more acceptable than turbulent structure models based on local flow properties. The results show that the turbulent kinetic energy approach is quite applicable to two-stream mixing problems, although the method requires further development before it is useful for routine engineering calculations. Calculations for a wake behind a flat plate are made and found to compare well with experimental data. The flux model for the diffusion of turbulent kinetic energy and the energy dissipation model were found to produce results which agree well with experimental data for both the mixing jet and the wake.