Modeling the "rapid" part of the velocity/pressure-gradient correlation in inhomogeneous turbulent flows
Svetlana V. Poroseva
备注：
15 pages, 2 figures, preliminary results were presented in the Proceed. Of the 3rd Inter. Symposium on Turbulence, Heat and Mass Transfer (Nagoya, Japan), 2000, pp. 487-493, and the initial draft was published in the Annual Research Brief 2001, Center for Turbulence Research, NASA-Ames/Stanford University, pp.367-374
A new model for the "rapid" part of the velocity/pressure-gradient correlation in the Reynolds averaged Navier-Stokes equations is suggested. It is shown that in an inhomogeneous incompressible turbulent flow, the model that is linear in the Reynolds stresses should include two model coefficients. A functional form of the coefficients is analyzed in some extreme turbulence states. As demonstrated, the proposed model reduces to the standard linear pressure-strain model in homogeneous turbulence and can satisfy realizability conditions provided the coefficients are functions of the mean velocity gradients and the Reynolds stresses. In an inhomogeneous turbulent flow, coefficients should depend on parameters directly related to inhomogeneous effects. The model is validated using direct numerical simulation data from two flows: the plane wake and the plane mixing layer.
A closure theory is developed for inhomogeneous turbulent flow, which enables a systematic derivation of the turbulence constitutive relations without relying on any empirical parameters. Renormalized-perturbation approximation is performed in the convective coordinate frame based on the mean flow, successfully incorporating the convective integration in generally covariant manner.
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A universal relation between intermittency and dissipation within and beyond homogeneous isotropic turbulence
Univ. Grenoble Alpes, CNRS, Grenoble INP（格勒诺布尔阿尔卑斯大学、法国国家科学研究中心、格勒诺布尔理工学院）；Institut für Physik und ForWind, Universität Oldenburg（奥尔登堡大学物理与风电研究所）；Univ. Lille, CNRS, ONERA, Arts et Métiers ParisTech, Centrale Lille（里尔大学、法国国家科学研究中心、法国航空国防技术局、巴黎国立高等工艺学院、中央理工学院）
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