A synthetic inflow generation method using the attached eddy hypothesis
A synthetic inflow generation method using the attached eddy hypothesis
复制标题
使用附加涡假设的合成流入流生成方法
DOI：
10.2514/6.2006-3672
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
I. Marusic
中科院分区：
文献类型：
--
作者：
P. Subbareddy;D. Peterson;G. Candler;I. Marusic
附加的涡流假设被用来发展一种产生合成湍流边界层的方法。波动速度场是使用毕奥-萨伐尔定律从简单的涡流形状创建的。这些与实验或RANS的平均速度剖面叠加，以创建可通过模拟的流入平面馈送的数据框。这提供了真实的随时间变化的流入数据。与其他合成流入生成方法相比，该方法在计算上是廉价的。两个流动使用这种方法进行了研究。第一部分采用分离涡模拟方法计算了马赫数分别为3和4时氦气垂直和斜喷入超音速湍流横流的情况。在每种情况下，喷射器的直径与横流的边界层厚度相当，并且可以预期，湍流边界层中的波动在射流的动力学中起重要作用。流场中氦的质量分数与实验数据进行了比较，结果令人鼓舞。第二种情况考虑的是超音速湍流混合层，其对流马赫数为0.46，雷诺数为12 × 106/m（基于速度差和平均ρ和μ）。两股气流通过一个薄的分流板汇合在一起，两边的边界层都是湍流。模拟进行了稳定的流入条件和合成湍流场。DES方法用于亚网格建模和结果进行了比较与实验的格贝尔和达顿。在非定常来流条件下，计算结果与试验结果吻合较好。
The attached eddy hypothesis is used to develop a means of generating synthetic turbulent boundary layers. Fluctuating velocity fields are created from simple vortex shapes using the Biot-Savart law. These are superposed with mean velocity profiles from experiment or RANS to create boxes of data which can be fed in through the inflow plane of a simulation. This provides realistic time varying inflow data. The method is computationally inexpensive compared with other synthetic inflow generation methods. Two flows are investigated using this approach. In the first, detached eddy simulation is used to compute normal and angled injection of helium into supersonic turbulent crossflows at Mach numbers 3 and 4 respectively. The diameter of the injector in each case is comparable to the boundary layer thickness of the crossflow and it is to be expected that fluctuations in the turbulent boundary layer play an important role in the dynamics of the jet. A comparison of the helium mass fraction in the flow field is made with experimental data and the results are encouraging. The second case considered is a supersonic turbulent mixing layer with ac onvective Mach number of0.46 and a Reynolds number of 12 × 10 6 /m (based on the velocity difference and average ρ and µ). The two streams are brought together across a thin splitter plate and the boundary layers on both sides are turbulent. Simulations are performed with steady inflow conditions and with the synthetic turbulent flow fields. The DES methodology is used for subgrid modelling and results are compared with the experiments of Goebel and Dutton. With unsteady inflow, the comparison with experiment was found to be very good.