High-resolution LES of a starting jet
High-resolution LES of a starting jet
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起始喷气机的高分辨率 LES
DOI：
10.1016/j.compfluid.2016.10.022
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发表时间：
2016
影响因子：
2.8
通讯作者：
A. Kempf
中科院分区：
文献类型：
--
作者：
E. Inanc;M. Nguyen;S. Kaiser;A. Kempf
通过高分辨率大涡模拟 (LES) 研究脉冲启动的射流。 Soulopoulos 等人对数值计算进行了介绍、分析并与实验数据进行了比较。 （2014）。模拟中采用不同的入口速度剖面及其湍流强度，通过将获得的混合分数及其耗散率与实验数据进行比较来确定适当的边界条件。对不同过滤器尺寸的数值计算进行了敏感性分析，并研究了入口流量的斜坡上升函数。模拟和实验之间达到了令人满意的一致性。结果发现，在我们的计算中观察到的势核在实验中不存在，这可能是由于喷嘴中的过早混合造成的。选择了两个参数，即混合分数及其耗散率进行统计评估，这两个参数都用于计算和实验。很明显，初始/边界条件影响流动动力学，因此可以观察到统计数据的显着差异。解析尺度的比较表明，模拟解析的结构比实验中的结构小两倍。然而，这不会导致数值和实验统计数据的差异，这与分辨率无关。可以看出，高标量耗散率 (SDR) 值主要位于混合层，但涡环则被相当低的 SDR 值占据。
An impulsively started jet is investigated by a highly resolved large-eddy simulation (LES). The numerical calculations are presented, analyzed and compared to the experimental data by Soulopoulos et al. (2014). Different inlet velocity profiles and their turbulence intensity are employed in the simulations to identify the appropriate boundary conditions by comparing the obtained mixture fraction and its dissipation rate against the experimental data. A sensitivity analysis of the numerical calculations to the different filter sizes is performed, and the ramp-up functions of the inlet flow are investigated. A satisfactory agreement between the simulation and the experiment is achieved. It is found that the potential core, which is observed in our calculations, was absent in the experiments, likely due to premature mixing in the nozzle.Two parameters, namely the mixture fraction and its dissipation rate, are chosen for the statistical evaluation, which is presented for both the calculation and the experiment. It is clear that the initial/boundary conditions influence the flow dynamics, thus considerable differences in the statistics can be observed. The comparison of the resolved scales shows that the simulation resolves structures smaller than those from the experiment by a factor of two. However, this does not lead to the discrepancy of the numerical and experimental statistics, which is independent of the resolution. It is observed that the high scalar dissipation rate (SDR) values are mainly located in the mixing layer, however the vortex ring is occupied by the considerably lower SDR values.
影响因子：
4.4
作者：
D. Butz;Yuan Gao;A. Kempf;N. Chakraborty
通讯作者：
D. Butz;Yuan Gao;A. Kempf;N. Chakraborty
湍流预混火焰大涡模拟的标量耗散率建模
影响因子：
3.4
作者：
Dunstan T
通讯作者：
Dunstan T