Numerical simulation of incompressible turbulent flows in presence of laminar to turbulent transition

15th Asian Congress of Fluid Mechanics

物理学;力学

Satish, G.^1 ; Vashista, G.A.^1 ; Majumdar, Sekhar^1

Center of Excellence for Computational Fluid Dynamics, Department of Mechanical Engineering, Nitte Meenakshi Institute of Technology, Bangalore

560064, India^1

关键词: Accurate prediction;    Chord-based Reynolds number;    Freestream turbulence;    Governing equations;    Incompressible turbulent flow;    Laminar to turbulent transitions;    Reliable measurement;    Transitional flow;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/822/1/012036/pdf
DOI  :  10.1088/1742-6596/822/1/012036

学科分类：力学，机械学

来源: IOP

【 摘 要 】

Most of the widely used popular mathematical models of turbulence use a judicious combination of intuition, empiricism and the governing equations of instantaneous and mean motion-valid strictly for fully developed turbulence without any laminar region. In reality however, any wall bounded or free shear flow may consist of some laminar flow patches which eventually undergo transition over a finite length to grow into fully turbulent flows. Most of the turbulence models used in commercial CFD codes, are unable to predict the dynamics of turbulent flows with laminar patches. However, accurate prediction of transitional flows is often essential to estimate the pressure losses and/or heat transfer in industrial applications. The present paper implements two different transition models in an existing finite volume URANS-based code RANS3D, developed in house and validated against reliable measurement data for flow past flat plates with different free stream turbulence levels and flow past SD7003 aerofoil at a chord-based Reynolds number of 60,000.