Effect of von Karman length scale in scale adaptive simulation approach on the prediction of supersonic turbulent flow

Abstract This paper follows the Prandtl conception of momentum transport and gives a critical examination of the so-called Prandtl-Nikuradse formula and the von Kármán formula for the velocity distribution of the turbulent flow in tubes or channels at large Reynolds number. It shows that both formulas would not give a good picture of the turbulent flow near the center of the conduit, and indeed they actually do not. A new formula for the velocity distribution is developed from a study of the mixing-length distribution across the section. This new formula checks quite well with the experiments and yields the same skin-friction formula as derived by von Kármán and Prandtl, which itself is in very good agreement with experiments.

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RETRACTED ARTICLE: Modeling and numerical simulation of baffles height effect on a Von Karman turbulent flow

Journal of Turbulence ◽

10.1080/14685248.2014.935856 ◽

2014 ◽

Vol 15 (12) ◽

pp. 807-832

Author(s):

Maher Raddaoui

Keyword(s):

Numerical Simulation ◽

Turbulent Flow ◽

Von Karman ◽

Retracted Article ◽

Von Kármán

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Stochastic Intermittency Fields in a von Kármán Experiment

Symmetry ◽

10.3390/sym13091752 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1752

Author(s):

Jürgen Schmiegel ◽

Flavio Pons

Keyword(s):

Time Series ◽

Energy Dissipation ◽

Turbulent Flow ◽

Turbulence Intensity ◽

Statistical Properties ◽

Close Resemblance ◽

Von Karman ◽

The One ◽

Von Kármán

We discuss the application of stochastic intermittency fields to describe and analyse the statistical properties of time series of the generalised turbulence intensity in an anisotropic and inhomogeneous turbulent flow and provide a parsimonious description of the one-, two-, and three-point statistics. In particular, we show that the three-point correlations can be predicted from observed two-point statistics. Our analysis is motivated by observed stylised features of the energy dissipation in homogeneous and isotropic situations where these statistical properties are well represented within the framework of stochastic intermittency fields. We find a close resemblance and conclude that stochastic intermittency fields may be relevant in more general situations.

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Study of the Shock Wave–Turbulent Boundary Layer Interaction Using a 3D von Kármán Length Scale

International Journal of Nonlinear Sciences and Numerical Simulation ◽

10.1515/ijnsns-2016-0018 ◽

2017 ◽

Vol 18 (1) ◽

pp. 57-66 ◽

Cited By ~ 1

Author(s):

Jing-Lei Xu ◽

You-Fu Song ◽

Yang Zhang ◽

Jun-Qiang Bai

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Turbulence Model ◽

High Speed ◽

Compressible Flows ◽

Separation Bubble ◽

Turbulence Models ◽

Length Scale ◽

Von Karman ◽

Von Kármán

AbstractTraditional turbulence models are initially formulated and calibrated under incompressible conditions. Thus, these models are always of low fidelity when extended to high speed, complex and compressible flows. In this work, a compressible von Kármán length scale is proposed for compressible flows considering the variable densities. The length scale is the ratio between the new vorticity and its gradient. The new length scale is actually based on phenomenological theory, which is then integrated into the KDO (turbulence Kinetic energy Dependent Only) turbulence model, arriving at a compressible model called CKDO (Compressible KDO). In the CKDO turbulence model, all the extra terms produced by compressibility are modeled as dissipation. Compression corners of 8, 16, 20 and 24 angles are studied within SST, SA, KDO and CKDO. These test cases are known as the typical shock wave–boundary layer interactions. The results show that the new length scale in CKDO is able to well capture the surface pressure and skin friction distributions. Besides, compared with the standard von Kármán length scale, the new length scale in CKDO can better capture the size and position of the separation bubble. With the increase of the corner angle, CKDO shows more prominent potential for describing compressible flows.

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