On Explicit Algebraic Stress Models For Complex Turbulent Flows

Download or read book On Explicit Algebraic Stress Models for Complex Turbulent Flows written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-09 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explicit algebraic stress models that are valid for three-dimensional turbulent flows in noninertial frames are systematically derived from a hierarchy of second-order closure models. This represents a generalization of the model derived by Pope who based his analysis on the Launder, Reece, and Rodi model restricted to two-dimensional turbulent flows in an inertial frame. The relationship between the new models and traditional algebraic stress models -- as well as anistropic eddy visosity models -- is theoretically established. The need for regularization is demonstrated in an effort to explain why traditional algebraic stress models have failed in complex flows. It is also shown that these explicit algebraic stress models can shed new light on what second-order closure models predict for the equilibrium states of homogeneous turbulent flows and can serve as a useful alternative in practical computations. Gatski, T. B. and Speziale, C. G. Langley Research Center NAS1-18605; NAS1-19480; RTOP 505-90-52-01...