Direct numerical simulation of thermal channel flow for medium–high Prandtl numbers up to Reτ=2000

Direct Numerical Simulation of the Wake Flow Behind a Cylinder Using Random Vortex Method in Medium to High Reynolds Numbers

Direct numerical simulation of turbulent flow behind a cylinder, wake flow, using the random vortex method for an incompressible fluid in two dimensions is presented. In the random vortex method, the primary variable is vorticity of the flow field. After generation on the cylinder wall, it is followed in two fractional time step in a Lagrangian system of coordinates, namely convection and diffu...

Direct numerical simulation of turbulent channel flow up to Re τ ≈ 5200

A direct numerical simulation of incompressible channel flow at Reτ = 5186 has been performed, and the flow exhibits a number of the characteristics of high Reynolds number wall-bounded turbulent flows. For example, a region where the mean velocity has a logarithmic variation is observed, with von Kármán constant κ = 0.384 ± 0.004. There is also a logarithmic dependence of the variance of the s...

Direct Numerical Simulation of Turbulent Heat Transfer in Pipe Flows with various Prandtl Numbers

The direct numerical simulation (DNS) of heat transfer in a fully developed turbulent pipe flow with for various Prandtle numbers are performed to obtain statistical quantities such as turbulent heat flux, and temperature variance. Main emphasis is placed on Prandtl number effects on turbulent heat transfer in pipe flow. Probability density functions and joint probability density functions of v...

Thermal convection for large Prandtl numbers.

The Rayleigh-Bénard theory by Grossmann and Lohse [J. Fluid Mech. 407, 27 (2000)] is extended towards very large Prandtl numbers Pr. The Nusselt number Nu is found here to be independent of Pr. However, for fixed Rayleigh numbers Ra a maximum in the Nu(Pr) dependence is predicted. We moreover offer the full functional dependences of Nu(Ra,Pr) and Re(Ra,Pr) within this extended theory, rather th...

Direct Numerical Simulation of Reacting Turbulent Multi-Species Channel Flow