A theoretical and experimental investigation of fiber suspension drainage in the turbulent regime: Part 1: Presentation of a new theory for the turbulent drainage of fiber suspensions

The present effort is the development of a multiscale modeling, simulation methodology for investigating complex phenomena arising from flowing fiber suspensions. The present approach is capable of coupling behaviors from the Kolmogorov turbulence scale through the full-scale system in which a fiber suspension is flowing. Here the key aspect is adaptive hierarchical modeling. Numerical results are presented for which focus is on fiber floc formation and destruction by hydrodynamic forces in turbulent flows. Specific consideration was given to dynamic simulations of viscoelastic fibers in which the fluid flow is predicted by a method that is a hybrid between direct numerical simulations and large eddy simulation techniques and fluid fibrous structure interactions will be taken into account. Dynamics of simple fiber networks in a shearing flow of water in a channel flow illustrate that the shear-induced bending of the fiber network is enhanced near the walls. Fiber-fiber interaction in straight ducts is also investigated and results show that deformations would be expected during the collision when the surfaces of flocs will be at contact. Smaller velocity magnitudes of the separated fibers compare to the velocity before collision implies the occurrence of an inelastic collision. In addition because of separation of vortices, interference flows around two flocs become very complicated. The results obtained may elucidate the physics behind the breakup of a fiber floc, opening the possibility for developing a meaningful numerical model of the fiber flow at the continuum level where an Eulerian multiphase flow model can be developed for industrial use.

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RESEARCH ON THE SPECIFIC VISCOSITY OF SEMI-CONCENTRATED FIBER SUSPENSIONS

Modern Physics Letters B ◽

10.1142/s0217984908017333 ◽

2008 ◽

Vol 22 (29) ◽

pp. 2857-2868

Author(s):

ZHANHONG WAN ◽

JIANZHONG LIN ◽

ZHENJIANG YOU ◽

HAI DING

Keyword(s):

Aspect Ratio ◽

Fiber Suspension ◽

Constructive Model ◽

Fiber Suspensions ◽

Small Aspect Ratio ◽

Concentric Cylinder ◽

Concentrated Suspensions ◽

Specific Viscosity ◽

Model Predictions ◽

Transient Shear Flow

The viscosity properties of the semi-concentrated suspensions of fibers with small aspect ratio were investigated in transient shear flow using a concentric cylinder geometry. Experimental results were compared with predictions by utilizing the constructive model developed by Batchelor in conjunction with the hybrid closure proposed by Advani and Tucker. To rectify the discrepancy between the theoretical prediction available at the present time and the measured data, a new expression for the specific viscosity in the semi-concentrated shear flows of fiber suspension is proposed allowing for the effects of the fiber–fiber interactions and the finite-aspect-ratio fiber. The results show that the model predictions for the fiber suspensions of different aspect ratio and concentration are fairly good.

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Rheological Behavior of Tomato Fiber Suspensions Produced by High Shear and High Pressure Homogenization and Their Application in Tomato Products

International Journal of Analytical Chemistry ◽

10.1155/2018/5081938 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Yong Wang ◽

Ping Sun ◽

He Li ◽

Benu P. Adhikari ◽

Dong Li

Keyword(s):

High Pressure ◽

Rheological Properties ◽

Loss Modulus ◽

Fiber Suspension ◽

High Pressure Homogenization ◽

Fiber Suspensions ◽

High Shear ◽

Fiber Concentration ◽

Tomato Ketchup ◽

And Storage

This study investigated the effects of high shear and high pressure homogenization on the rheological properties (steady shear viscosity, storage and loss modulus, and deformation) and homogeneity in tomato fiber suspensions. The tomato fiber suspensions at different concentrations (0.1%–1%, w/w) were subjected to high shear and high pressure homogenization and the morphology (distribution of fiber particles), rheological properties, and color parameters of the homogenized suspensions were measured. The homogenized suspensions were significantly more uniform compared to unhomogenized suspension. The homogenized suspensions were found to better resist the deformation caused by external stress (creep behavior). The apparent viscosity and storage and loss modulus of homogenized tomato fiber suspension are comparable with those of commercial tomato ketchup even at the fiber concentration as low as 0.5% (w/w), implying the possibility of using tomato fiber as thickener. The model tomato sauce produced using tomato fiber showed desirable consistency and color. These results indicate that the application of tomato fiber in tomato-based food products would be desirable and beneficial.

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Experimental investigation of convective heat transfer using ethylene glycol-based nano-fluid

E3S Web of Conferences ◽

10.1051/e3sconf/202123900022 ◽

2021 ◽

Vol 239 ◽

pp. 00022

Author(s):

Muhammad Shoaib Rafiq ◽

Hafiz Muhammad Ali ◽

Amir Sultan

Keyword(s):

Heat Transfer ◽

Experimental Investigation ◽

Heat Transfer Coefficient ◽

Ethylene Glycol ◽

Transfer Coefficient ◽

Convective Heat Transfer ◽

Convective Heat ◽

Convective Heat Transfer Coefficient ◽

Turbulent Regime ◽

Nano Fluid

Coolant plays important characteristic in automobile industry to prevent failure and damage by balancing the temperature. Due to this approach, coolants are being used as new thermal fluid to study the heat transfer coefficient performance. This study consists of an experimental investigation of internal convective heat transfer of 50:50 Water-Ethylene Glycol based Nano-fluid through a copper tube of 18mm external diameter and 16.5mm internal diameter and a test section of 1m in a fully turbulent regime. Total convective heat transfer coefficient of Nano fluid at three different volumetric concentrations of nanoparticles is estimated. Local convective heat transfer at eight different points along the tube at varying Reynolds number is also determined. At 0.15% volumetric concentration of SiO2 Nanoparticles (NPS) 29% increment in convective heat transfer coefficient (CHT) is observed. The decrease in the heat transfer rate is observed with changing distance axially. Particles disorganized movement of NPs and undulation in the fluid and increased in thermal conductivity of Nano fluid can be possible reason for extra ordinary change in heat transfer.

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Morphologies and characteristic of glass fiber suspensions basing on various beating speeds

Materials Express ◽

10.1166/mex.2019.1609 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1043-1048

Author(s):

Zhou Chen ◽

Yong Yang ◽

Tengzhou Xu ◽

Junfeng Hu ◽

Shaoqiang Liu

Keyword(s):

Glass Fiber ◽

Fiber Length ◽

Random Distribution ◽

Glass Fibers ◽

Fiber Suspension ◽

Fiber Suspensions ◽

Fiber Contact

Glass fibers commonly flocculate in suspensions and slurries, which can be largely prevented by a beating process. In this paper, morphologies and characteristics of glass fiber suspensions resulting from various beating speeds are explored. By increasing the speed (ranging from 1500 revolutions to 12000 revolutions), glass fibers can be translated, rotated, bended and broken, which leads the drainage resistances of glass fiber suspensions increase dramatically from 19.5 °SR to 23.5 °SR, then fluctuate and settle close to 22.5 °SR. Decreasing the fiber length leads to reduction in fiber–fiber contact and improves the uniformity of fiber suspensions. The separation and random distribution of glass fibers decreases in the viscosity of the fiber suspension.

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Fiber Suspensions in Turbulent flow with Two-Point Correlation

Bangladesh Journal of Scientific and Industrial Research ◽

10.3329/bjsir.v46i2.8206 ◽

1970 ◽

Vol 46 (2) ◽

pp. 265-270 ◽

Cited By ~ 2

Author(s):

SE Ahmed ◽

MS Alam Sarker

Keyword(s):

Mathematical Modeling ◽

Flow Field ◽

Turbulent Flow ◽

Pressure Fluctuations ◽

Equation Of Motion ◽

Second Order ◽

Fiber Suspension ◽

Fiber Suspensions ◽

Velocity Fluctuations ◽

Point Correlation

The equation of motion for turbulent flow of fiber suspensions has been derived in terms of correlation tensors of second order. Mathematical modeling of fiber suspensions in the turbulent flow is discussed including the correlation between the pressure fluctuations and velocity fluctuations at two points of the flow field, where the correlation tensors are the functions of space coordinates, distance between two points and the time. Keywords: Fiber suspension; Turbulent flow; Correlation.DOI: http://dx.doi.org/10.3329/bjsir.v46i2.8206 Bangladesh J. Sci. Ind. Res. 46(2), 265-270, 2011

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Experimental Investigation of Pressure Distribution in Turbulent Flow Between Parallel and Inclined Disks

Journal of Fluids Engineering ◽

10.1115/1.4030764 ◽

2015 ◽

Vol 137 (11) ◽

Cited By ~ 2

Author(s):

Daniel A. Eisenberg ◽

Cesar J. Deschamps

Keyword(s):

Experimental Investigation ◽

Turbulent Flow ◽

Pressure Distribution ◽

Radial Flow ◽

Numerical Study ◽

High Accuracy ◽

Experimental Results ◽

Turbulent Regime ◽

Complex Flow ◽

Simple Representation

Although the flow between parallel and inclined disks is a simple representation of many complex flow situations, this class of flow poses significant problems for experimental and numerical study. This paper presents experimental results of the pressure distribution for turbulent radial flow between parallel and inclined disks, considering different ratios between the diameters of the frontal disk and feeding orifice. The experimental results bolster the lack of data for both flow situations in the turbulent regime and demonstrate differences between them. The results presented have high accuracy and known uncertainty, making them useful for comparison to analytical and numerical results.

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