Assessment of non-local effect on pressure term in RANS modeling using a DNS database
Assessment of non-local effect on pressure term in RANS modeling using a DNS database
复制标题
使用 DNS 数据库评估 RANS 建模中压力项的非局部影响
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
P. Durbin
中科院分区：
文献类型：
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作者：
R. Manceau;M. Wang;P. Durbin
利用Reτ = 590的通道流的DNS数据库，研究了用于模拟椭圆松弛的雷诺应力输运方程中的压力项的假设的有效性。结果表明，由指数函数描述的脉动速度和压力梯度的拉普拉斯算子的相关函数实际上不是各向同性的。它不仅在流向上是细长的，而且在垂直于壁面的方向上是不对称的。这一特征是椭圆松弛算子预测的对数层中雷诺应力分量之间的再分布略有放大的主要原因。预期的减少再分配预测的模型，它可以通过占相关函数的不对称性，而不使用任何壁回波校正项的一个新的配方。通过目前的DNS分析，这种减少是由于壁回波效应的信念受到质疑。
A DNS database for the channel flow at Reτ = 590 is used to investigate the validity of the hypotheses used to model the pressure term in the Reynolds stress transport equations by elliptic relaxation. It is shown that the correlation function involving the fluctuating velocity and the Laplacian of the pressure gradient, which is modeled by an exponential function, is actually not isotropic. It is not only elongated in the streamwise direction but also asymmetric in the direction normal to the wall. This feature is the main cause for the slight amplification of the redistribution between the Reynolds stress components in the log layer as predicted by the elliptic relaxation operator. The expected reduction in redistribution is predicted by a new formulation of the model, which can be derived by accounting for the asymmetry in the correlation function, without using any wall echo correction terms. The belief that this reduction is due to the wall echo effect is called into question through the present DNS analysis.