The Effect of Varying Viscosity in Turbulent Channel Flow

  title={The Effect of Varying Viscosity in Turbulent Channel Flow},
  author={Victor Coppo Leite and Elia Merzari},
  journal={Volume 3: Computational Fluid Dynamics; Micro and Nano Fluid Dynamics},
  • V. Leite, E. Merzari
  • Published 9 June 2020
  • Physics
  • Volume 3: Computational Fluid Dynamics; Micro and Nano Fluid Dynamics
In this article we examine channel flow subject to spatially varying viscosity in the streamwise direction. The Reynolds number is imposed locally with three different ramps. The setup is reminiscent of transient channel flow, but with a space-dependent viscosity rather than a time dependent viscosity. It is also relevant to various applications in nuclear engineering and in particular in test reactors, where the viscosity changes significantly in the streamwise direction, and there is a… 
Turbulent Channel Flow With Spatially Dependent Viscosity: A Numerical Study
In this study, we examine in detail the effect of spatially dependent viscosity on wall-bounded flow. For this purpose, direct numerical simulations (DNS) are performed considering a channel flow
A New RANS Correction to Account for Varying Viscosity Effects
  • V. Leite, E. Merzari
  • Physics
    Volume 1: Aerospace Engineering Division Joint Track; Computational Fluid Dynamics
  • 2021
It has previously been shown that by increasing the Reynolds number across a channel by spatially varying the viscosity does not cause an immediate change in the size of turbulent structures and a


Transition of transient channel flow after a change in Reynolds number
Abstract It has previously been shown that the transient flow in a channel following a step increase of Reynolds number from 2800 to 7400 (based on channel half-height and bulk velocity) is
A study of turbulence under conditions of transient flow in a pipe
A detailed investigation of fully developed transient flow in a pipe has been undertaken using water as the working fluid. Linearly increasing or decreasing excursions of flow rate were imposed
Reynolds number effects on the Reynolds-stress budgets in turbulent channels
Budgets for the nonzero components of the Reynolds-stress tensor are presented for numerical channels with Reynolds numbers in the range Reτ=180–2000. The scaling of the different terms is discussed,
Rapid temporal acceleration of a turbulent pipe flow
Measurements were made of fully developed turbulent pipe flows subjected to temporal pressure gradients larger than those considered previously. Integral profile parameters exhibited similar
The dynamic structure of turbulence in transient pipe flows was studied experimentally. Two types of stepwise change in the flow rate of a fully developed pipe flow showed apparently different
CFD validation in OECD/NEA t-junction benchmark.
When streams of rapidly moving flow merge in a T-junction, the potential arises for large oscillations at the scale of the diameter, D, with a period scaling as O(D/U), where U is the characteristic
Critical Evaluation of Two-Equation Models for Near-Wall Turbulence
Abstract : A variety of two-equation turbulence models - including several versions of the K-epsilon model as well as the K-omega model - are analyzed critically for near wall turbulent flows from a
Quantitative characterization of coherent structures in the buffer layer of near-wall turbulence. Part 1: streaks
Streaks play a major role in the process of turbulent generation. Numerous studies have been performed to characterize them, most of which used only single point measurements and only a few
Experimental study of eddy structures in a turbulent boundary layer using particle image velocimetry
Particle image velocimetry experiments have been performed in a turbulent boundary-layer wind tunnel in order to study the coherent structures taking part in the generation and preservation of wall