Destabilization and Aggregation in Turbulent Pipe Flow

Silica suspensions (pH = 6.8) and three different cationic polymers were used to study the kinetics of charge neutralization by polyelectrolyte adsorption. The experiments were performed in a continuous flow pipe reactor under steady state turbulent flow conditions. The charge neutralization was monitored by electrophoretic mobility (EPM) measurements of the suspended particles as a function of time after polyelectrolyte audition. The results show the dependency of the destabilization reaction rate on flow and polymer characteristics.

Intermediate scaling and logarithmic invariance in turbulent pipe flow

Journal of Fluid Mechanics ◽

10.1017/jfm.2021.71 ◽

2021 ◽

Vol 913 ◽

Author(s):

Sourabh S. Diwan ◽

Jonathan F. Morrison

Keyword(s):

Pipe Flow ◽

Turbulent Pipe Flow

Abstract

Experimental and theoretical progress in pipe flow transition

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2008.0063 ◽

2008 ◽

Vol 366 (1876) ◽

pp. 2671-2684 ◽

Cited By ~ 34

Author(s):

A.P Willis ◽

J Peixinho ◽

R.R Kerswell ◽

T Mullin

Keyword(s):

Pipe Flow ◽

Quantitative Agreement ◽

Travelling Wave ◽

Turbulent Pipe Flow ◽

Transition To Turbulence ◽

Reynolds Number Flow ◽

Threshold Amplitude ◽

Number Flow ◽

The Stability ◽

Laminar State

There have been many investigations of the stability of Hagen–Poiseuille flow in the 125 years since Osborne Reynolds' famous experiments on the transition to turbulence in a pipe, and yet the pipe problem remains the focus of attention of much research. Here, we discuss recent results from experimental and numerical investigations obtained in this new century. Progress has been made on three fundamental issues: the threshold amplitude of disturbances required to trigger a transition to turbulence from the laminar state; the threshold Reynolds number flow below which a disturbance decays from turbulence to the laminar state, with quantitative agreement between experimental and numerical results; and understanding the relevance of recently discovered families of unstable travelling wave solutions to transitional and turbulent pipe flow.

Rapid temporal acceleration of a turbulent pipe flow

Journal of Fluid Mechanics ◽

10.1017/s0022112004000114 ◽

2004 ◽

Vol 514 ◽

pp. 65-75 ◽

Cited By ~ 38

Author(s):

DAVID GREENBLATT ◽

EDWARD A. MOSS

Keyword(s):

Pipe Flow ◽

Turbulent Pipe Flow

CFD modelling of entropy generation in turbulent pipe flow: Effects of temperature difference and swirl intensity

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2016.02.014 ◽

2016 ◽

Vol 100 ◽

pp. 999-1006 ◽

Cited By ~ 11

Author(s):

Khalid M. Saqr ◽

Ali I. Shehata ◽

Ahmed A. Taha ◽

Mohamed M. Abo ElAzm

Keyword(s):

Entropy Generation ◽

Temperature Difference ◽

Pipe Flow ◽

Turbulent Pipe Flow ◽

Cfd Modelling ◽

Swirl Intensity ◽

Effects Of Temperature ◽

Flow Effects

Velocity measurements made with a laser dopplermeter on the turbulent pipe flow of a dilute polymer solution

Journal of Fluid Mechanics ◽

10.1017/s0022112072001302 ◽

1972 ◽

Vol 51 (4) ◽

pp. 673-685 ◽

Cited By ~ 64

Author(s):

M. J. Rudd

Keyword(s):

Polymer Solution ◽

Velocity Component ◽

Pipe Flow ◽

Viscous Sublayer ◽

Turbulent Pipe Flow ◽

Velocity Measurements ◽

Velocity Fluctuations ◽

Conventional Models ◽

Drag Reducing Polymer ◽

Spanwise Velocity

This paper presents some new measurements which have been made on a drag-reducing polymer solution in pipe flow. A novel type of laser dopplermeter, which has been developed by the author, is briefly described and the measurements which have been obtained are given. These results and their implications are then discussed in terms of conventional models for turbulent flow in a pipe. These suggest that the polymer has very little effect upon the turbulent core of the flow, but thickens and stabilizes the viscous sublayer. The turbulent intensity inside the sublayer is unchanged but, owing to its thickening, the velocity fluctuations just outside are greater. There is not a general suppression of turbulence within the sublayer although well inside the sublayer the spanwise velocity component is found to be reduced.