Corrigenda to the paper by G I Barenblatt, A J Chorin, V M Prostokishin "Turbulent flows at very large Reynolds numbers: new lessons learned" (Usp. Fiz. Nauk, March 2014, Vol. 184, No. 3, pp. 265—272)

This chapter introduces the main ideas behind the application of LBE methods to the problem of turbulence modeling, namely the simulation of flows which contain scales of motion too small to be resolved on present-day and foreseeable future computers. Many real-life flows of practical interest exhibit Reynolds numbers far too high to be directly simulated in full resolution on present-day computers and arguably for many years to come. This raises the challenge of predicting the behavior of highly turbulent flows without directly simulating all scales of motion which take part to turbulence dynamics, but only those that fall within the computer resolution at hand.

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Can Bump Arrays Separate Particles From Turbulent Flows?

10.1115/fedsm2021-67696 ◽

2021 ◽

Author(s):

Leonard F. Pease ◽

Jason Serkowski ◽

Timothy G. Veldman ◽

Jonathan Willams ◽

Xiao-Ying Yu ◽

...

Keyword(s):

Turbulent Flows ◽

Particle Separation ◽

Reynolds Numbers ◽

Industrial Scale ◽

Flow Rates ◽

Scale Particle ◽

Experimental Findings

Abstract In this paper, we evaluate the hypothesis that bump arrays can be used to separate particles from turbulent flows entering the array. Microfluidic bump arrays are known for separating particles by size from laminar inlet flows. However, turbulent inlet flows have not been explored but become important as microfluidic bump arrays are scaled up to mesofluidic bump arrays. We find experimentally that particle separation is indeed effective at higher Reynolds numbers. These experimental findings portend industrial scale particle separation due to the higher flow rates they facilitate.

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Measurement and Prediction of the Effects of Nonuniform Surface Roughness on Turbulent Flow Friction Coefficients

Journal of Fluids Engineering ◽

10.1115/1.3243567 ◽

1988 ◽

Vol 110 (4) ◽

pp. 380-384 ◽

Cited By ~ 20

Author(s):

R. P. Taylor ◽

W. F. Scaggs ◽

H. W. Coleman

Keyword(s):

Turbulent Flows ◽

Rough Surfaces ◽

Reynolds Numbers ◽

Base Diameter ◽

Friction Coefficients ◽

Friction Factors ◽

Random Rough Surfaces ◽

The Status ◽

Uniform Array ◽

Prediction Approach

The status of prediction methods for friction coefficients in turbulent flows over nonuniform or random rough surfaces is reviewed. Experimental data for friction factors in fully developed pipe flows with Reynolds numbers between 10,000 and 600,000 are presented for two nonuniform rough surfaces. One surface was roughened with a mixture of cones and hemispheres which had the same height and base diameter and were arranged in a uniform array. The other surface was roughened with a mixture of two sizes of cones and two sizes of hemispheres. These data are compared with predictions made using the previously published discrete element prediction approach of Taylor, Coleman, and Hodge. The agreement between the data and the predictions is excellent.

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